CN103414650B

CN103414650B - A kind of avoid congested method for routing and device

Info

Publication number: CN103414650B
Application number: CN201310323965.XA
Authority: CN
Inventors: 洪佩琳; 朱超; 周伟
Original assignee: Shanghai Huawei Technologies Co Ltd
Current assignee: Shanghai Huawei Technologies Co Ltd
Priority date: 2013-07-29
Filing date: 2013-07-29
Publication date: 2016-12-07
Anticipated expiration: 2033-07-29
Also published as: CN103414650A

Abstract

A kind of congested method for routing and device avoided, wherein, the method includes: receive the LSA message that in network, each first network element sends；Construct overall network topology figure；Receive the NCA message that in network, each first network element sends；Obtain global congestion information；Obtain each node and go to the optimal path of other node in network；Obtain the maximum rate of influx that described optimal path allows；According to described global congestion information, nodes being in congestion state all in network are removed from topological diagram the network topological diagram obtaining non-congested state；According to the network topological diagram of non-congested state, obtain optimal path during non-congested；According to the optimal path of described acquisition, the maximum rate of influx that described optimal path is allowed, and optimal path during described non-congested, obtain forwarding strategy, and it being sent to corresponding first network element so that described first network element obtains stream table list item according to described forwarding strategy, and stores.Thus avoid congested, improve data transmission efficiency.

Description

A kind of avoid congested method for routing and device

Technical field

The present invention relates to communication technical field, avoid congested method for routing and device particularly to a kind of.

Background technology

Along with the growth of internet scale, the user on the Internet and application all increase quickly, congested Have become as a highly important problem.In recent years, substantial amounts of research has been carried out in congestion control field Work, congestion control algorithm can be divided into two major parts, it may be assumed that on end system use source algorithm and The link algorithm used on the network equipment.

Source algorithm it is to be understood that occur congested time, source reduce send data speed, thus Make the substantial amounts of connection can shared link.By source, the perception of current network state and detection are rung Should adjust the window size that packet occurs, undoubtedly, the extensibility that this algorithm provides promotes interconnection Net fast development in early days.Along with the development of technology, the cognition to the effect that the node in network is played Gradually deeply, Queue Management Algorithm is thus proposed.Queue Management Algorithm is by management routing queue head Degree arranges a maximum to each queue, then receives bag and enters queue until queue length reaches maximum Value, the packet of follow-up arrival will be dropped, i.e. tail dropping algorithm (DT, Drop Tail).

Prior art also proposed Active Queue for Management Mechanism (AQM, Active Queue Management), wherein, in early days random drop (RED, Random Early Detection) be based on Most representative scheme in the AQM of queue length.RED algorithm is by detecting the average team of intermediate node Row length q detects network congestion, and by notifying that TCP sender sends out with certain probability dropping packet Raw congested.Packet dropping probability in RED algorithm is a function about q, and it is by receiving Packet is limited in below certain level, and burst type can be avoided to abandon the number from same connection continuously According to bag.Shown in following formula (1):

P = \{\begin{matrix} 0, & q \leq q_{\min} \\ P_{\max} \frac{q - q_{\min}}{q_{\max} - q_{\min}}, & q_{\min} < q < q_{\max} \\ 1, & q_{\max} < q \end{matrix} - - - (1)

Wherein, q_min, q_max, it is minimum threshold and the max-thresholds of queue, the most permissible by formula (1) Calculate the probability that packet abandons.As it is shown in figure 1, the drop probability of RED algorithm is with average queue length Change meets piecewise linear relationship.

From the point of view of the technical scheme of above-mentioned existing solution congestion problems, this simply avoiding of tail dropping algorithm is gathered around The method of plug, can occur to synchronize the phenomenon of packet loss in a network, and each data stream is affected by DT algorithm, Constantly increase and reduce window, thus cause network cycle between congested and idle two states Wave, cause the decline of link utilization.AQM algorithm can avoid synchronizing in network packet loss phenomenon, but It is that this algorithm starts packet loss the most in advance and can cause the waste of Internet resources when network does not occurs congested.

Therefore, prior art is not provided that one is more reasonable, the technical scheme more optimized.

Summary of the invention

The embodiment of the present invention provides a kind of and avoids congested method for routing and device, makes full use of the team of node Row caching, can avoid again congestion packet loss phenomenon simultaneously, the problem solving network congestion from source.

First aspect, it is provided that a kind of avoid congested method for routing, including:

First network element obtains information of neighbor nodes, generates Link State according to the information of neighbor nodes obtained public Accuse LSA message, and LSA message is sent to controller；

Described first network element obtains congestion state bulletin NCA message, and described NCA message is sent to institute State controller, wherein, described NCA message includes the congestion information of described first network element.

In the implementation that the first is possible, according to first aspect, the congestion information of described first network element Specifically by the congested rate matrix P of described first network element_iRepresent；

P_{i} = \overset{1}{[\begin{matrix} p_{1, i} \\ \cdot \\ \cdot \\ \cdot \\ p_{j, i} \\ \cdot \\ \cdot \\ \cdot \\ p_{n, i} \end{matrix}]}

Wherein, P_iFor the two-dimensional matrix of n × 1, n represents the number of the first network element, p in region_j,iRepresent number Enter the maximum allowable ingress rate of the first network element i from the first network element j according to stream, wherein, the first network element i is First network element of described method executive agent；

Wherein, p_j,iValue be such as following formula:

P_{j, i} = \{\begin{matrix} \frac{λ_{j \cdot i}}{λ_{i}} \cdot u_{i}, & λ_{i} &GreaterEqual; μ_{i}, q_{i} &GreaterEqual; Q_{th}; \\ \infty, & else; \end{matrix}

Wherein, λ_j,iRepresent the streaming rate entering the first network element i from the first network element j；λ_iRepresent all Entering the speed sum of the first network element i, value isu_iRepresent all and leave the first network element i Streaming rate sum, value isq_iRepresent the queue length of the first network element, when λ_i≥μ_i, and q_iThreshold value Q more than or equal to the first network element length_thTime, described first network element is in be gathered around Plug-like state.

In the implementation that the second is possible, in conjunction with first aspect or implementation that the first is possible, Described method also includes:

Described first network element is transmitted into and leaves the numerical value of streaming rate of described first network element, described Enter and leave the numerical value of the streaming rate of described first network element, in controller, obtain structure when number It is drop probabilities ρ during UDP message stream according to stream_iStrategy.

Second aspect, it is provided that a kind of avoid congested method for routing, including:

Receive the LSA message that in network, each first network element sends；According to described LSA message, construct complete Office network topological diagram；

Receive the NCA message that in network, each first network element sends；According to described NCA message, obtain complete Office's congestion information；

According to described overall network topology figure, obtain each node and go to the optimum road of other node in network Footpath；

According to described global congestion information, and the optimal path of described acquisition, obtain the optimum of described acquisition The maximum rate of influx that path allows；

According to described global congestion information, by nodes of congestion state that are in all in network from topological diagram Except the network topological diagram obtaining non-congested state；According to the network topological diagram of non-congested state, obtain non-gathering around Optimal path during plug；

According to the optimal path of described acquisition, the maximum rate of influx that the optimal path of described acquisition is allowed, With optimal path during described non-congested, obtain forwarding strategy, obtain stream table table according to described forwarding strategy , and it is sent to corresponding first network element；

Wherein, according to the optimal path of described acquisition, the maximum inflow that the optimal path of described acquisition is allowed Speed, and optimal path during described non-congested, obtain forwarding strategy, specifically include:

If when the optimal path of described acquisition there being the first network element be in congestion state, it is desirable to described acquisition Source node first network element of optimal path be two data streams, wherein, one by the data flow point of reception The maximum rate of influx that data stream allows with the optimal path that speed is described acquisition, according to described acquisition Optimal path forwards；Speed v of another data stream data stream to receive, with the optimum of described acquisition The speed of the difference of the maximum rate of influx that path is allowed, forwards according to optimal path during described non-congested.

In the implementation that the first is possible, according to second aspect, according to the optimal path of described acquisition, The maximum rate of influx that the optimal path of described acquisition is allowed, and optimal path during described non-congested, Obtain forwarding strategy, also specifically include:

When speed v of the data stream received in source node first network element of the optimal path of described acquisition is less than The maximum rate of influx that the optimal path of described acquisition is allowed, by described data stream with speed be described in obtain The maximum rate of influx that the optimal path taken is allowed, forwards according to the optimal path of described acquisition.

In the implementation that the second is possible, according to first aspect, or the first of first aspect can The implementation of energy, each NCA message includes the congestion information of first network element, described first net The congestion information of unit is specifically by the congested rate matrix P of described first network element_iRepresent；

P_{i} = \overset{1}{[\begin{matrix} p_{1, i} \\ \cdot \\ \cdot \\ \cdot \\ p_{j, i} \\ \cdot \\ \cdot \\ \cdot \\ p_{n, i} \end{matrix}]}

Wherein, p_j,iValue be such as following formula:

P_{j, i} = \{\begin{matrix} \frac{λ_{j \cdot i}}{λ_{i}} \cdot u_{i}, & λ_{i} &GreaterEqual; μ_{i}, q_{i} &GreaterEqual; Q_{th}; \\ \infty, & else; \end{matrix}

Wherein, λ_j,iRepresent the streaming rate entering the first network element i from the first network element j；λ_iRepresent institute Having the speed sum entering the first network element i, value isu_iRepresent all and leave the first net The streaming rate sum of unit i, value isq_iRepresent the queue length of the first network element, Work as λ_i≥μ_i, and q_iThreshold value Q more than or equal to the first network element length_thTime, described first network element It is in congestion state；

According to described NCA message, obtain global congestion information, specifically include:

According to the congestion information of the first network element that described NCA message includes, construct global congestion speed Matrix P, it may be assumed that

P=[P₁ ... P_i ... P_n]

Wherein, n represents the number of the first network element, P in region_iCongested rate matrix for described first network element.

In the implementation that the third is possible, in conjunction with the implementation that the second is possible, described according to institute Stating global congestion information, and the optimal path of described acquisition, the optimal path obtaining described acquisition is allowed Maximum rate of influx, specifically include:

From global congestion information and in the optimal path of described acquisition, obtain the optimal path of described acquisition Middle previous dive k_i-1To down hop k_iMaximum allowable ingress rate

Obtain maximum allowable ingress rate minimum in the optimal path of described acquisition, as described acquisition The maximum rate of influx p that optimal path is allowed, i.e. Wherein, S is the source node of the optimal path of described acquisition, and D is the purpose joint of the optimal path of described acquisition Point.

In the 4th kind of possible implementation, in conjunction with second aspect, realization possible in second aspect first Mode to implementation possible in second aspect the 3rd, any one, described according to obtain optimum road Footpath, the maximum rate of influx that the optimal path of described acquisition is allowed, and optimum road during described non-congested Footpath, obtains forwarding strategy, particularly as follows:

According to the optimal path of described acquisition, the maximum rate of influx that the optimal path of described acquisition is allowed, With optimal path during described non-congested, obtaining the data stream when receiving in the first network element is tcp data stream Time forwarding strategy.

In the 5th kind of possible implementation, in conjunction with second aspect, described method also includes:

Receive the streaming rate entering and leaving each first network element that each first network element sends；

Described according to described overall network topology figure, obtain each node and go to the optimum of other node in network After path, described method also includes:

When the data stream received in the first network element is UDP message stream, enter and leave each the according to described The streaming rate of one network element, constructs drop probabilities ρ_iStrategy；

According to described drop probabilities ρ_iStrategy, and the optimal path of described acquisition, obtain when in the first network element The data stream received is forwarding strategy during UDP message stream；

By described when in the first network element receive data stream be forwarding strategy during UDP message stream, be made as Stream table list item, is sent to the first network element of described correspondence.

In the 6th kind of possible implementation, in conjunction with the 5th kind of possible implementation of second aspect, described When the data stream received in the first network element is UDP message stream, enter and leave each first net according to described The streaming rate of unit, constructs drop probabilities ρ_iStrategy, specifically include:

Using equation below as the drop probabilities when the data stream received in the first network element is for UDP message stream ρ_iStrategy:

ρ_{i} = \{\begin{matrix} 0, & q_{i} < Q_{th}; \\ \frac{λ_{i} - u_{i}}{λ_{i}}, & λ_{i} &GreaterEqual; μ_{i}, Q_{th} \leq q_{i} < Q_{\max}; \\ 1, & q_{i} &GreaterEqual; Q_{\max}; \end{matrix}

Wherein, λ_i、u_iIt is respectively the data stream entering and leaving the first network element i of described first reported by network elements Speed, q_iIt is the queue length of the first network element i, Q_thIt is the threshold value length of the first network element i, Q_maxFor The maximum allowable queue length of the first network element i；

Described according to described drop probabilities ρ_iStrategy, and the optimal path of described acquisition, obtain when corresponding the The data stream received in one network element is forwarding strategy during UDP message stream, specifically includes:

When the queue length of the first network element is less than threshold value length, all UDP message bags are all with described The optimal path obtained forwards；

When the queue length of the first network element is more than or equal to threshold value length and less than maximum allowable queue length, And first network element ingress rate more than leave speed time, withProbability packet loss, residue UDP message bag forward with the optimal path of described acquisition；

When the queue length of the first network element is more than its maximum allowable queue length, described first net of all entrance The UDP message bag of unit all will be dropped.

The third aspect, it is provided that a kind of avoid congested method for routing, including:

Receive data stream；According to the stream table list item of storage, it is two data by the data flow point of described reception Circulation is sent out,

Wherein, a data stream is the maximum that in described stream table list item, the optimal path of record allows with speed Rate of influx, forwards according to the optimal path of record in described stream table list item；

Another data stream is to record in speed v of the data stream of described reception, with described stream table list item The speed of the difference of the maximum rate of influx that shortest path is allowed, gathers around according to the non-of record in described stream table list item Optimal path during plug forwards.

In the implementation that the first is possible, according to the third aspect, another data stream described is with described The maximum inflow that in speed v of the data stream received, with described stream table list item, the optimal path of record is allowed The speed of the difference of speed, forwards according to the optimal path during non-congested recorded in described stream table list item, it Before, described method also includes:

For the optimal path institute of record in speed v of the data stream with described reception, with described stream table list item The speed of the difference of the maximum rate of influx allowed, another data stream of forwarding, in another data described The data packet header of stream arranges sign, for distinguishing the data stream that this data stream is congested shunting.

In the implementation that the second is possible, according to the third aspect, described method also includes:

If the described optimal path of record is in non-congested state, according to described stream table in described stream table list item In list item, the optimal path of record forwards described data stream.

In the implementation that the third is possible, in conjunction with the third aspect or implementation that the first is possible or The implementation that the second is possible, the described stream table list item according to storage, by the data flow point of described reception Before being two forwarding data flows, described method also includes:

Whether the data stream judging described reception is tcp data stream, if tcp data stream, performs institute State the stream table list item according to storage, be two forwarding data flows by the data flow point of described reception.

In the 4th kind of possible implementation, in conjunction with the third possible implementation of the third aspect, institute Method of stating also includes:

When the data stream judging described reception is not tcp data stream, according to record in described stream table list item Perform forwarding, specifically include:

When in described first network element, the queue length of packet is more than or equal to threshold value length, and it is less than Allow greatly queue length, and the ingress rate of described first network element is more than when leaving speed, with ρ_iProbability Packet loss, remaining UDP message bag forwards with the optimal path of record in stream table list item；Wherein, ρ_iFor institute State the drop probabilities recording the first network element i in stream table list item；

When the queue length of the first network element is more than its maximum allowable queue length, all entrance described first The UDP message bag of network element all will be dropped.

Fourth aspect, it is provided that a kind of network element, described network element includes: the first acquiring unit, and first sends Unit, second acquisition unit, and the second transmitting element；

Described first acquiring unit, is used for obtaining information of neighbor nodes, according to the information of neighbor nodes obtained Generate LSA LSA message；

Described first transmitting element, for being sent to controller by LSA message；

Described second acquisition unit, is used for obtaining congestion state bulletin NCA message, wherein, described NCA Message includes the congestion information of described network element；

Described second transmitting element, for being sent to described controller by described NCA message.

In the implementation that the first is possible, according to fourth aspect, the congestion information of described network element is concrete By the congested rate matrix P of described network element_iRepresent；

P_{i} = \overset{1}{[\begin{matrix} p_{1, i} \\ \cdot \\ \cdot \\ \cdot \\ p_{j, i} \\ \cdot \\ \cdot \\ \cdot \\ p_{n, i} \end{matrix}]}

Wherein, P_iFor the two-dimensional matrix of n × 1, n represents the number of network element, p in region_j,iRepresent data stream Enter the maximum allowable ingress rate of network element i from network element j, wherein, network element i is described method executive agent Network element；

Wherein, p_j,iValue be such as following formula:

P_{j, i} = \{\begin{matrix} \frac{λ_{j \cdot i}}{λ_{i}} \cdot u_{i}, & λ_{i} &GreaterEqual; μ_{i}, q_{i} &GreaterEqual; Q_{th}; \\ \infty, & else; \end{matrix}

Wherein, λ_j,iRepresent the streaming rate entering network element i from network element j；λ_iRepresent all entrance network element i Speed sum, value isu_iRepresent all streaming rate sums leaving network element i, Value isq_iRepresent the queue length of network element, work as λ_i≥μ_i, and q_iMore than or equal to network element The threshold value Q of length_thTime, described network element is in congestion state.

In the implementation that the second is possible, in conjunction with fourth aspect, or the first possible realization side Formula, described second transmitting element, it is additionally operable to be transmitted into and leave the number of the streaming rate of described network element Value, described in enter and leave the numerical value of streaming rate of described network element, in controller, obtain structure Drop probabilities ρ when data stream is UDP message stream_iStrategy.

5th aspect, it is provided that a kind of controller, described controller includes:

First receives unit, the first structural unit, and second receives unit, and the 3rd acquiring unit, the 4th obtains Take unit, the 5th acquiring unit, the 6th acquiring unit, the 7th acquiring unit, the 3rd transmitting element；

Described first receives unit, for receiving the LSA message that in network, each first network element sends；

Described first structural unit, for according to described LSA message, constructs overall network topology figure；

Described second receives unit, for receiving the NCA message that in network, each first network element sends；

Described 3rd acquiring unit, for according to described NCA message, obtains global congestion information；

Described 4th acquiring unit, for according to described overall network topology figure, obtains each node and goes to net The optimal path of other node in network；

Described 5th acquiring unit, is used for according to described global congestion information, and the optimum road of described acquisition Footpath, obtains the maximum rate of influx that the optimal path of described acquisition allows；

Described 6th acquiring unit, for according to described global congestion information, gathers around all being in network The node of plug-like state removes the network topological diagram obtaining non-congested state from topological diagram；According to non-congested shape The network topological diagram of state, obtains optimal path during non-congested；

Described 7th acquiring unit, for the optimal path according to described acquisition, the optimal path of described acquisition The maximum rate of influx allowed, and optimal path during described non-congested, obtain forwarding strategy, according to Described forwarding strategy obtains stream table list item；

If when the optimal path obtained has the first network element to be in congestion state, it is desirable to described acquisition is The data flow point of reception is two data streams by source node first network element of shortest path, wherein, and data Flow the maximum rate of influx allowed with the optimal path that speed is described acquisition, according to the optimum of described acquisition Path forwards；Speed v of another data stream data stream to receive, with the optimal path of described acquisition The speed of the difference of the maximum rate of influx allowed, forwards according to optimal path during described non-congested；

Described 3rd transmitting element, for being sent to described first network element by the described stream table list item obtained.

In the implementation that the first is possible, according to the 5th aspect, for root in described 7th acquiring unit According to the optimal path of described acquisition, the maximum rate of influx that the optimal path of described acquisition is allowed, and institute State optimal path during non-congested, obtain forwarding strategy, also specifically include:

Speed v of the data stream received when source node first network element of the optimal path of described acquisition is less than institute State the maximum rate of influx that the optimal path of acquisition is allowed, be described acquisition by described data stream with speed The maximum rate of influx that allowed of optimal path, forward according to the optimal path of described acquisition.

In the implementation that the second is possible, in conjunction with the 5th aspect, receive in the second reception unit is every Individual NCA message includes the congestion information of first network element, and the congestion information of described first network element is concrete By the congested rate matrix P of described first network element_iRepresent；

P_{i} = \overset{1}{[\begin{matrix} p_{1, i} \\ \cdot \\ \cdot \\ \cdot \\ p_{j, i} \\ \cdot \\ \cdot \\ \cdot \\ p_{n, i} \end{matrix}]}

Wherein, p_j,iValue be such as following formula:

P_{j, i} = \{\begin{matrix} \frac{λ_{j \cdot i}}{λ_{i}} \cdot u_{i}, & λ_{i} &GreaterEqual; μ_{i}, q_{i} &GreaterEqual; Q_{th}; \\ \infty, & else; \end{matrix}

Wherein, λ_j,iRepresent the streaming rate entering the first network element i from the first network element j；λ_iRepresent all enter Entering the speed sum of the first network element i, value isu_iRepresent all and leave the first network element i's Streaming rate sum, value isq_iRepresent the queue length of the first network element, work as λ_i≥μ_i, And q_iThreshold value Q more than or equal to the first network element length_thTime, described first network element is in congestion state；

For according to described NCA message in 3rd acquiring unit, obtain global congestion information, specifically include:

P=[P₁ ... P_i ... P_n]

In the implementation that the third is possible, in conjunction with the implementation that the second is possible, the described 5th obtains Take in unit, be used for according to described global congestion information, and the optimal path of described acquisition, obtain described The maximum rate of influx that the optimal path obtained is allowed, specifically includes:

In the 4th kind of possible implementation, in conjunction with the 5th aspect or implementation that the first is possible extremely Any one of the third possible implementation, for according to described acquisition in described 7th acquiring unit Optimal path, the maximum rate of influx that the optimal path of described acquisition is allowed, and during described non-congested Optimal path, obtain forwarding strategy, particularly as follows:

The described optimal path according to described acquisition, the maximum inflow speed that the optimal path of described acquisition is allowed Rate, and optimal path during described non-congested, obtaining the data stream when receiving in corresponding first network element is TCP Forwarding strategy during data stream.

In the 5th kind of possible implementation, in conjunction with the 5th aspect, described second receives unit, also uses In receiving the streaming rate entering and leaving each first network element that each first network element sends；

Described controller also includes:

Second structural unit and the 4th transmitting element；

Described second structural unit, is used at described 4th acquiring unit according to described overall network topology figure, Obtain each node and go in network after the optimal path of other node, when corresponding first network element receives Data stream when being UDP message stream, according to the described streaming rate entering and leaving each first network element, Structure drop probabilities ρ_iStrategy；

Described 4th transmitting element, for by described when in corresponding first network element receive data stream be UDP Forwarding strategy during data stream, is made as stream table list item, is sent to the first network element of described correspondence.

In the 6th kind of possible implementation, in conjunction with the 5th kind of possible implementation of the 5th aspect, described Second structural unit is used for when the data stream received in corresponding first network element is UDP message stream, according to The described streaming rate entering and leaving each first network element, constructs drop probabilities ρ_iStrategy, specifically wrap Include:

Using equation below as the packet loss when the data stream received in corresponding first network element is for UDP message stream Probability ρ_iStrategy:

ρ_{i} = \{\begin{matrix} 0, & q_{i} < Q_{th}; \\ \frac{λ_{i} - u_{i}}{λ_{i}}, & λ_{i} &GreaterEqual; μ_{i}, Q_{th} \leq q_{i} < Q_{\max}; \\ 1, & q_{i} &GreaterEqual; Q_{\max}; \end{matrix}

When the queue length of the first network element is more than or equal to threshold value length also, less than maximum allowable queue length And first network element ingress rate more than leave speed time, withProbability packet loss, remaining UDP message bag forwards with the optimal path of described acquisition；

6th aspect, it is provided that a kind of network element, described network element includes: the 4th receives unit, and first turn Bill unit；

Described 4th receives unit, is used for receiving data stream；

Described first retransmission unit, for the stream table list item according to storage, by the data flow point of described reception It is two forwarding data flows；Wherein, a data stream is the optimum of record in described stream table list item with speed The maximum rate of influx that path allows, forwards according to the optimal path of record in described stream table list item；Another Prop up data stream speed v with the data stream of described reception, with the optimal path institute of record in described stream table list item The speed of difference of the maximum rate of influx allowed, according in described stream table list item during the non-congested of record Shortest path forwards.

In the implementation that the first is possible, according to the 6th aspect, described network element also includes: identifying sheet list Unit,

Described sign unit, for described first retransmission unit record according to described stream table list item non- Before optimal path time congested forwards, for speed v of the data stream with described reception, with described stream table The speed of the difference of the maximum rate of influx that the optimal path of record is allowed, another number of forwarding in list item According to stream, the data packet header at another data stream described arranges sign, and being used for distinguishing this data stream is to gather around The data stream of plug shunting.

In the implementation that the second is possible, according to the 6th aspect, described network element, also include: second Retransmission unit,

Described second retransmission unit, if the described optimal path of record is in non-in described stream table list item Congestion state, forwards described data stream according to the optimal path of record in described stream table list item.

In the implementation that the third is possible, in conjunction with the 6th aspect or implementation that the first is possible, Or the implementation that the second is possible, described network element also includes: the second judging unit,

Described second judging unit, is used at described first retransmission unit according to the stream table list item stored, will Before the data flow point of described reception is two forwarding data flows, it is judged that whether the data stream of described reception is Tcp data stream；

Described first retransmission unit, is additionally operable to, if tcp data stream, perform the described stream according to storage Table list item, is two forwarding data flows by the data flow point of described reception.

In the 4th kind of possible implementation, in conjunction with implementation possible in the 6th aspect the 3rd, institute State network element also to include: the 3rd retransmission unit,

Described 3rd retransmission unit, is used for when the data stream judging described reception is not tcp data stream, Perform forwarding according to record in described stream table list item, specifically include:

When in described network element, the queue length of packet is more than or equal to threshold value length and fair less than maximum Permitted queue length；And the ingress rate of described network element is more than when leaving speed, withProbability Packet loss, remaining UDP message bag forwards with the optimal path of record in stream table list item；Wherein, ρ_iFor institute State the drop probabilities recording network element i in stream table list item；

When the queue length of network element is more than its maximum allowable queue length, the described network element of all entrance UDP message bag all will be dropped.

7th aspect, it is provided that a kind of network element, described network element includes the input dress being connected respectively in bus Put, output device, memorizer and processor；

Described processor, for according to the information of neighbor nodes obtained from input equipment, according to the neighbour obtained Occupy nodal information and generate LSA LSA message；Congestion state bulletin NCA is obtained from input equipment Message, wherein, includes the congestion information of described network element in described NCA message；

Described output device, for being sent to controller by LSA message；Described NCA message is sent To described controller.

In the implementation that the first is possible, according to the 7th aspect, the congestion information of described network element is concrete By the congested rate matrix P of described network element_iRepresent；

P_{i} = \overset{1}{[\begin{matrix} p_{1, i} \\ \cdot \\ \cdot \\ \cdot \\ p_{j, i} \\ \cdot \\ \cdot \\ \cdot \\ p_{n, i} \end{matrix}]}

Wherein, p_j,iValue be such as following formula:

P_{j, i} = \{\begin{matrix} \frac{λ_{j \cdot i}}{λ_{i}} \cdot u_{i}, & λ_{i} &GreaterEqual; μ_{i}, q_{i} &GreaterEqual; Q_{th}; \\ \infty, & else; \end{matrix}

Wherein, λ_j,iRepresent the streaming rate entering network element i from network element j；λ_iRepresent all entrance network element i's Speed sum, value isu_iRepresent all streaming rate sums leaving network element i, take Value isq_iRepresent the queue length of network element, work as λ_i≥μ_i, and q_iMore than or equal to network element length Threshold value Q_thTime, described network element is in congestion state.

In the implementation that the second is possible, according to the 7th aspect or the 7th aspect, the first is possible Implementation, described output device, it is additionally operable to be transmitted into and leave the streaming rate of described network element Numerical value, described in enter and leave the numerical value of streaming rate of described network element, in controller, obtain structure Make drop probabilities ρ when data stream is UDP message stream_iStrategy.

Eighth aspect, it is provided that a kind of controller, it is defeated that described controller includes being connected respectively in bus Enter device, output device, memorizer and processor；

Described input equipment, for receiving the LSA message that in network, each first network element sends；Receive network In each first network element send NCA message；

Described processor, for according to described LSA message, constructs overall network topology figure；According to institute State NCA message, obtain global congestion information；According to described overall network topology figure, obtain each joint Point goes to the optimal path of other node in network；According to described global congestion information, and described acquisition Optimal path, obtains the maximum rate of influx that the optimal path of described acquisition allows；Gather around according to the described overall situation Nodes being in congestion state all in network are removed from topological diagram and are obtained non-congested state by plug information Network topological diagram；According to the network topological diagram of non-congested state, obtain optimal path during non-congested； According to the optimal path of described acquisition, the maximum rate of influx that the optimal path of described acquisition is allowed, and Optimal path during described non-congested, obtains forwarding strategy, obtains stream table list item according to described forwarding strategy；

Described output device, for being sent to described first network element by the described stream table list item obtained.

In the implementation that the first is possible, according to eighth aspect, for according to described in described processor The optimal path obtained, the maximum rate of influx that the optimal path of described acquisition is allowed, and described non-gather around Optimal path during plug, obtains forwarding strategy, also specifically includes:

In the implementation that the second is possible, in conjunction with the implementation that the first is possible, described input fills The each NCA message putting reception includes the congestion information of first network element, described first network element Congestion information is specifically by the congested rate matrix P of described first network element_iRepresent；

P_{i} = \overset{1}{[\begin{matrix} p_{1, i} \\ \cdot \\ \cdot \\ \cdot \\ p_{j, i} \\ \cdot \\ \cdot \\ \cdot \\ p_{n, i} \end{matrix}]}

Wherein, p_j,iValue be such as following formula:

P_{j, i} = \{\begin{matrix} \frac{λ_{j \cdot i}}{λ_{i}} \cdot u_{i}, & λ_{i} &GreaterEqual; μ_{i}, q_{i} &GreaterEqual; Q_{th}; \\ \infty, & else; \end{matrix}

For according to described NCA message in described processor, obtain global congestion information, specifically include:

P=[P₁ ... P_i ... P_n]

In the implementation that the third is possible, in conjunction with the implementation that eighth aspect the second is possible, institute State in processor, be used for according to described global congestion information, and the optimal path of described acquisition, obtain institute State the maximum rate of influx that the optimal path of acquisition is allowed, specifically include:

In the 4th kind of possible implementation, in conjunction with eighth aspect or implementation that the first is possible extremely The third possible implementation any one, for according to the optimum road of described acquisition in described processor Footpath, the maximum rate of influx that the optimal path of described acquisition is allowed, and optimum road during described non-congested Footpath, obtains forwarding strategy, particularly as follows:

In the 5th kind of possible implementation, in conjunction with the 4th kind of possible implementation of eighth aspect, institute State input equipment, be additionally operable to receive the data stream entering and leaving each first network element that each first network element sends Speed；

Described processor is additionally operable to:

According to described overall network topology figure, obtain each node and go to the optimum road of other node in network After footpath, when the data stream received in corresponding first network element is UDP message stream, according to described entrance and Leave the streaming rate of each first network element, construct drop probabilities ρ_iStrategy；

By described when in corresponding first network element receive data stream be forwarding strategy during UDP message stream, system As stream table list item, it is sent to the first network element of described correspondence.

In the 6th kind of possible implementation, in conjunction with the 5th kind of possible implementation of eighth aspect, described In processor for when in corresponding first network element receive data stream be UDP message stream time, according to described enter Enter and leave the streaming rate of each first network element, construct drop probabilities ρ_iStrategy, specifically include:

ρ_{i} = \{\begin{matrix} 0, & q_{i} < Q_{th}; \\ \frac{λ_{i} - u_{i}}{λ_{i}}, & λ_{i} &GreaterEqual; μ_{i}, Q_{th} \leq q_{i} < Q_{\max}; \\ 1, & q_{i} &GreaterEqual; Q_{\max}; \end{matrix}

9th aspect, it is provided that a kind of network element, described network element includes the input dress being connected respectively in bus Put, output device, memorizer and processor；

Described input equipment, is used for receiving data stream；

Described processor, for the stream table list item according to storage, is two by the data flow point of described reception Forwarding data flow；Wherein, a data stream is that in described stream table list item, the optimal path of record is permitted with speed The maximum rate of influx permitted, forwards according to the optimal path of record in described stream table list item；Another data Stream is allowed with the optimal path of record in speed v of the data stream of described reception, with described stream table list item The speed of the difference of maximum rate of influx, according to the optimal path during non-congested recorded in described stream table list item Forward.

In the implementation that the first is possible, according to the 9th aspect, described processor, it is additionally operable to described Before optimal path during the non-congested that the first retransmission unit records according to described stream table list item forwards, The optimal path of record in speed v of the data stream with described reception, with described stream table list item is allowed The speed of difference of maximum rate of influx, another data stream of forwarding, at another data stream described Data packet header arranges sign, for distinguishing the data stream that this data stream is congested shunting.

In the implementation that the second is possible, in conjunction with the first possible implementation of the 9th aspect, institute State processor, if the described optimal path being additionally operable in described stream table list item record is in non-congested state, Described data stream is forwarded according to the optimal path of record in described stream table list item.

In the implementation that the third is possible, in conjunction with the 9th aspect or implementation that the first is possible Or the implementation that the second is possible, it is characterised in that described processor, is additionally operable to described first Retransmission unit according to storage stream table list item, by the data flow point of described reception be two forwarding data flows it Before, it is judged that whether the data stream of described reception is tcp data stream；

Described processor, is additionally operable to, if tcp data stream, perform the described stream table list item according to storage, It is two forwarding data flows by the data flow point of described reception.

In the 4th kind of possible implementation, in conjunction with the implementation that the third is possible, described processor, It is additionally operable to when the data stream judging described reception is not tcp data stream, remembers according in described stream table list item Record performs forwarding, specifically includes:

The embodiment of the present invention provides a kind of congested method for routing and device avoided, program middle controller root Obtain LSA message and NCA message according to each switch from network, construct overall network topology figure with complete Office's congestion information, according to overall network topology figure and global congestion information, constructs switch and gathers around being in Two paths under plug-like state, data flow point that will be congested is two data streaming, a data stream Can bear speed with original path, according to this original path transmission, another data stream of shunting is gathered around with non- Optimal path transmission under plug-like state.Thus the prior art packet discard avoided cause efficiency of transmission The best problem, substantially increases efficiency of transmission.

Accompanying drawing explanation

In order to be illustrated more clearly that the embodiment of the present invention or technical scheme of the prior art, below will be to reality Execute the required accompanying drawing used in example or description of the prior art to be briefly described, it should be apparent that below, Accompanying drawing in description is only some embodiments of the present invention, for those of ordinary skill in the art, On the premise of not paying creative work, it is also possible to obtain other accompanying drawing according to these accompanying drawings.

Fig. 1 is the drop probability piecewise linear relationship schematic diagram of RED algorithm in prior art；

Fig. 2 is that in SDN, between Open Flow switch and controller, message forwards simplified schematic diagram；

Fig. 3 is the stream table simplified schematic diagram of storage in Open Flow switch；

Fig. 4 is a kind of SDN simplified schematic diagram；

What Fig. 5 was that the embodiment of the present invention provides a kind of avoids congested method for routing general flow chart；

Fig. 6 is that the embodiment of the present invention provides two a kind of of offer to avoid congested method for routing general flow chart；

Fig. 7 is that the embodiment of the present invention provides four a kind of of offer to avoid congested method for routing general flow chart；

Fig. 8 a is that the embodiment of the present invention provides a kind of of five offers to avoid congested method for routing flow elements letter Figure；

Fig. 8 b is that the embodiment of the present invention provides a kind of of five offers to avoid congested method for routing flow elements letter Figure；

Fig. 9 is the LSB message simplified schematic diagram that each switch is sent to controller；

Figure 10 is the NCA message simplified schematic diagram that each switch is sent to controller；

Figure 11 is bottom overall network topology figure simplified schematic diagram；

Figure 12 is the signal letter of the optimal path from source node to destination node of controller structure non-congested network Figure；

Figure 13 is stream table list item simplified schematic diagram in switch；

Figure 14 is to distinguish tcp data stream and the stream table list item simplified schematic diagram of UDP message stream in switch；

Figure 15 is a kind of network element simplified schematic diagram that the embodiment of the present invention six provides；

Figure 16 is a kind of controller simplified schematic diagram that the embodiment of the present invention seven provides；

Figure 17 is a kind of network element simplified schematic diagram that the embodiment of the present invention nine provides；

Figure 18 is a kind of network element simplified schematic diagram that the embodiment of the present invention ten provides；

Figure 19 is a kind of controller simplified schematic diagram that the embodiment of the present invention 11 provides；

Figure 20 is a kind of network element simplified schematic diagram that the embodiment of the present invention 12 provides.

Detailed description of the invention

Below in conjunction with the accompanying drawing in the embodiment of the present invention, the technical scheme in the embodiment of the present invention is carried out Clearly and completely describe, it is clear that described embodiment is only a part of embodiment of the present invention, and It is not all, of embodiment.Based on the embodiment in the present invention, those of ordinary skill in the art are not making Go out the every other embodiment obtained under creative work premise, broadly fall into the scope of protection of the invention.

Before the technical scheme providing the embodiment of the present invention is described in detail, this programme is suitable for Software defined network (SDN, Software Defined Networking) illustrates, SDN be for Conventional network equipment and a change of framework, its core concept is that forwarded controls to separate with network. Open flows (Open Flow) is considered as SDN thought one specific implementation.As in figure 2 it is shown, The message repeating process that Open Flow will be controlled by switch and router completely, is converted into by Open Flow Switch (Open Flow Switch) and controller (Controller) complete jointly, it is achieved thereby that Data forward and the separation of route test.Controller can be controlled by the interface operation provided in advance Stream table (stream table simplified schematic diagram as shown in Figure 3) in Open Flow switch, thus reach to control data and turn The purpose sent out.

As shown in Figure 4, a kind of SDN, including a controller and multiple switch.Each exchange Machine all passes through escape way (such as dotted arrow in Fig. 2) and is connected with controller.Switch is responsible for inquiring about stream table And forward data, controller to be responsible for monitoring network and constructing stream table.Data stream flows through region as shown in Figure 2 During network, at each switch, the stream table in inquiry switch, if this data stream did not register, Then this traffic flow information (mainly data stream header information) is sent to controller, by controlling by switch Device is that this stream generates forwarding strategy, and makes stream table list item according to forwarding strategy；If this data stream and friendship Stream table coupling in changing planes, then this data stream is carried out associative operation according to the action of stream table by switch.Need It being understood that the limit not to the embodiment of the present invention of the Local Area Network under the SDN framework shown in Fig. 4 System, is only easy for a kind of explanation understood, the technical scheme that the embodiment of the present invention provides can be with indifference Be generalized in various types of SDN.

The technical scheme provided the embodiment of the present invention below in conjunction with specific embodiment elaborates.

Embodiment one

Embodiments providing and a kind of avoid congested method for routing, the method is each from network The operating process that the angle of switch is write, wherein, the equipment described in the present embodiment is not limiting as being exchange Machine, it is also possible to using the first network element as executive agent, this first network element can be switch, it is also possible to be Network node, or a kind of controller etc., should not be construed the embodiment of the present invention is present herein, In literary composition, other embodiments have similar understanding.

As it is shown in figure 5, the method includes:

Step 101, switch obtains information of neighbor nodes, generates link according to the information of neighbor nodes obtained State advertisements LSA message；And LSA message is sent to controller；

Wherein, in network, each switch is regular, or when neighbor node changes, by self Information of neighbor nodes passes through LSA message, is sent to controller, for controller according to the neighbour of each switch Occupy nodal information, construct overall network topology figure；And, for controller by congested switch Network topological diagram after (or node) is removed, under structure non-congested state.

Step 102, switch obtains congestion state bulletin NCA message, is sent by described NCA message To described controller, wherein, described NCA message includes the congestion information of described switch.

It is to be appreciated that the gathering around of the switch that includes of NCA message that in network, each switch sends Plug information, gets global congestion information, it is simple to subsequent controllers is to routing forwarding in controller Control.

Wherein, the congestion information of switch is specifically by the congested rate matrix P of described switch_iRepresent；

P_{i} = \overset{1}{[\begin{matrix} p_{1, i} \\ \cdot \\ \cdot \\ \cdot \\ p_{j, i} \\ \cdot \\ \cdot \\ \cdot \\ p_{n, i} \end{matrix}]}

Wherein, P_iFor the two-dimensional matrix of n × 1, n represents the number of switch, p in region_j,iRepresent data Flowing the maximum allowable ingress rate entering switch i from switch j, wherein, switch i is described method The switch of executive agent；

Wherein, p_j,iValue be such as following formula:

P_{j, i} = \{\begin{matrix} \frac{λ_{j \cdot i}}{λ_{i}} \cdot u_{i}, & λ_{i} &GreaterEqual; μ_{i}, q_{i} &GreaterEqual; Q_{th}; \\ \infty, & else; \end{matrix}

Wherein, λ_j,iRepresent the streaming rate entering switch i from switch j；λ_iRepresent all entrance The speed sum of switch i, value isu_iRepresent all data stream leaving switch i Speed sum, value isq_iRepresent the queue length of switch, work as λ_i≥μ_i, and q_i Threshold value Q more than or equal to switch length_thTime, described switch is in congestion state, such as above formula institute Show, under switch is in congestion state, its maximum allowable ingress rate p_j,iReport control, inform control Device processed, this switch is in congestion state.

A kind of by the explanation of above-mentioned the present embodiment one avoids congested method for routing, in the program in network Switch, by the information of neighbor nodes of self and self congestion information, is sent by LSA and NCA respectively To controller, controller each switch in network is managed collectively, constructs overall network topology figure, With global congestion information so that controller, according to described overall network topology figure, obtains each node and goes to The optimal path of other node in network；According to described global congestion information, and described optimal path, obtain Take the maximum rate of influx that described optimal path allows；According to described global congestion information, by institute in network The node being in congestion state is had to remove the network topological diagram obtaining non-congested state from topological diagram；According to The network topological diagram of non-congested state, obtains optimal path during non-congested；Optimum according to described acquisition Path, the maximum rate of influx that described optimal path is allowed, and optimal path during described non-congested, Obtain forwarding strategy, and make stream table list item, stream table list item is sent to corresponding switch so that described Switch obtains stream table list item, and stores；Wherein, according to the optimal path of described acquisition, described optimum The maximum rate of influx that path is allowed, and optimal path during described non-congested, obtain forwarding strategy, Specifically include:

When speed v of the data stream received in described corresponding switch is more than what described optimal path was allowed Maximum rate of influx, then be two data streams by the data flow point of described reception, wherein, and a data stream It is the maximum rate of influx that described optimal path allows with speed, forwards according to the optimal path of described acquisition； Another data stream is with speed v of the data stream of described reception, the maximum allowed with described optimal path The speed of the difference of rate of influx, forwards according to optimal path during described non-congested.

Therefore, the method that this example demonstrates that, compared with prior art, it is to avoid as simple in tail dropping algorithm Abandon the packet exceeding queue max threshold length, also overcome and just do not shift to an earlier date when network occurs congested Start packet loss and can cause the problem of waste of Internet resources, it is provided that a kind of more reasonably avoid congested side Method, thus ensure the quality that data are transmitted, provide the user the service of higher efficiency.

Preferably, the method can also include: the first network element is transmitted into and leaves the number of described switch According to the numerical value of flow velocity rate, this enters and leaves the numerical value of streaming rate of described first network element, is used for controlling Device processed obtains structure drop probabilities ρ when data stream is UDP message stream_iStrategy.

Embodiment two

The embodiment of the present invention provides a kind of and avoids in congested method for routing, the method and above-described embodiment one The method illustrated, is based on different executive agents respectively, with controller as executive agent in this embodiment, Plan as a whole forwarding strategy for each switch, forwarding strategy be fabricated to stream table list item, be sent to each switch, As switch flows table list item.Switch utilizes the forwarding of controller to control, and can effectively avoid gathering around Plug, effective transmission of the most guaranteed data.

The detailed description of the method, with reference to shown in accompanying drawing 6, the method includes:

Step 201, receives the LSA message that in network, each switch sends；According to described LSA message, Construct overall network topology figure；

Step 202, receives the NCA message that in network, each switch sends；According to described NCA message, Obtain global congestion information；

Wherein, the congestion information that the NCA message that each switch sends includes, specifically it is referred to State in embodiment one congested rate matrix P in step 102_iExplanation.Each switch is got at controller Congested rate matrix P_i, construct global congestion rate matrix P, it may be assumed that

P=[P₁ ... P_i ... P_n]

Wherein, n represents the number of switch, P in region_iCongested rate matrix for described switch.

Step 203, according to described overall network topology figure, obtains each node and goes to other node in network Optimal path；

Step 204, according to described global congestion information, and described optimal path, obtain described optimal path The maximum rate of influx allowed；

It should be noted that step 204 can specifically include:

From global congestion information and in described optimal path, obtain previous dive k in described optimal path_i-1Arrive Down hop k_iMaximum allowable ingress rate

Obtain maximum allowable ingress rate minimum in described optimal path, permitted as described optimal path The maximum rate of influx p permitted, i.e.Wherein, S is institute Stating the source node of optimal path, D is the destination node of described optimal path.

Step 205, according to described global congestion information, by nodes being in congestion state all in network from Topological diagram is removed the network topological diagram obtaining non-congested state；According to the network topological diagram of non-congested state, Obtain optimal path during non-congested；

Step 206, according to the optimal path of described acquisition, the maximum inflow speed that described optimal path is allowed Rate, and optimal path during described non-congested, obtain forwarding strategy；Wherein, according to described acquisition Shortest path, the maximum rate of influx that described optimal path is allowed, and optimal path during described non-congested, Obtain forwarding strategy, specifically include:

If when optimal path there being switch be in congestion state, it is desirable to the source node of this optimal path is handed over Changing planes the data flow point of described reception is two data streams, and wherein, a data stream is described with speed The maximum rate of influx that optimal path allows, forwards according to the optimal path of described acquisition；Another data Flow speed v with the data stream of described reception, the maximum rate of influx allowed with described optimal path The speed of difference, forwards according to optimal path during described non-congested.

Wherein it is desired to understand, when there being switch to be in congestion state on path, then can be understood as this road Footpath is congested, and therefore, its respective congestion information is reported exchange by each switch in optimal path Machine, therefore, controller is after getting optimal path, for being in congested exchange on optimal path During machine it will be apparent that, if there being switch to be in congestion state on optimal path, then controller understands this Shortest path is in congested, then by the data flow point of input be two-way forward.

Step 207, according to above-mentioned forwarding strategy structure stream table list item, and is sent to corresponding switch so that Described switch takes stream table list item, and stores.Wherein, described corresponding switch can be optimal path Source node switch, also includes all of switch in network, when switch is not the source joint of optimal path During point switch, this switch does not perform the task of streamed data stream, and is carried out transmitting data flow and arrives down One jumps.For in the present embodiment, the source node switch of optimal path, mainly according to controller structure Stream table list item, performs streamed data stream the operation forwarded, and other switches only perform to forward operation.

By the above-mentioned explanation to the embodiment of the present invention two, program middle controller is respectively handed over according to from network Change planes and obtain LSA message and NCA message, construct overall network topology figure and global congestion information, root According to overall network topology figure and global congestion information, construct two under being in congestion state of switch Path, data flow point that will be congested is two data streaming, and a data stream can hold with original path By speed, according to this original path transmission, another data stream of shunting is with the optimum under non-congested state Path transmission.Thus the prior art packet discard avoided cause the best problem of efficiency of transmission, greatly Improve greatly efficiency of transmission.

Preferably, optimal path according to described acquisition in above-mentioned steps 206, described optimal path is allowed Maximum rate of influx, and optimal path during described non-congested, obtain forwarding strategy, also specifically include:

Step 206a, when speed v of the data stream received in the source node switch of described optimal path is little In the maximum rate of influx that described optimal path is allowed, it is described optimum road by described data stream with speed The maximum rate of influx that footpath is allowed, forwards according to the optimal path of described acquisition.

The forwarding strategy that the controller of above-mentioned increase generates, and make stream table list item according to forwarding strategy, its Effect is when congestion condition does not occurs in switch, as according to the optimal path constituted according to Global Topological figure Transmitting data flow.

Preferably, it should be noted that data stream type may include that transmission control protocol (TCP, Transmission Control Protocol) data stream and UDP (UDP, User Datagram Protocol) data stream.Wherein, UDP message stream is mainly real time type data stream, the feature of this kind of business Being higher to requirement of real-time, the requirement for packet loss is relatively low, and for the packet abandoned Retransmission process will not be carried out；The data stream using Transmission Control Protocol transmission is mainly data class data flow, this kind of industry It is engaged in requiring higher for packet loss, relatively low to requirement of real-time, and if network occurring, packet loss is existing , all can carry out retransmission process for the packet abandoned, if the frequent packet loss of such Business Stream, will Cause substantial amounts of data packet retransmission, cause network congestion condition to deteriorate further.Therefore, above-mentioned steps 206 The forwarding strategy of middle acquisition, specifically includes:

Step 206b, the described optimal path according to described acquisition, the maximum that described optimal path is allowed Rate of influx, and optimal path during described non-congested, obtaining the data stream received in each switch is TCP Forwarding strategy during data stream.Wherein, described each switch includes the source node switch of optimal path With the switch on each paths, but switch indicates in stream table list item being primarily referred to as of streamed data stream The source node switch of optimal path, the switch in the middle of path only performs forwarding task, does not perform shunting The operation of data stream.The follow-up understanding to switch has similar explanation, repeats the most one by one.

Further, if the data stream received in switch is UDP message stream, described method also includes:

Receive the streaming rate entering and leaving each switch that each switch sends；

After step 203, this controller can also carry out following steps:

Step 208, when the data stream received in corresponding switch is UDP message stream, according to described enter Enter and leave the streaming rate of each switch, drop probabilities ρ of structure packet_iStrategy；

Step 209, according to described drop probabilities ρ_iStrategy, and the optimal path of described acquisition, obtain and work as The data stream received in corresponding switch is forwarding strategy during UDP message stream；

Wherein, when in step 208, when the data stream received in corresponding switch is UDP message stream, According to the described streaming rate entering and leaving each switch, drop probabilities ρ of structure packet_iPlan Slightly, specifically include:

General using equation below as the packet loss when the data stream received in corresponding switch is for UDP message stream Rate ρ_iStrategy:

ρ_{i} = \{\begin{matrix} 0, & q_{i} < Q_{th}; \\ \frac{λ_{i} - u_{i}}{λ_{i}}, & λ_{i} &GreaterEqual; μ_{i}, Q_{th} \leq q_{i} < Q_{\max}; \\ 1, & q_{i} &GreaterEqual; Q_{\max}; \end{matrix}

Wherein, λ_i、u_iIt is respectively the streaming rate entering and leaving switch i that switch reports, q_i For the queue length of switch i, Q_thFor the threshold value length of switch i, Q_maxMaximum for switch i Allow queue length；

Described according to described drop probabilities ρ_iStrategy, and the optimal path of described acquisition, obtain when correspondence is handed over The data stream of middle reception of changing planes is forwarding strategy during UDP message stream, specifically includes:

When the queue length of switch is less than threshold value length, all UDP message bags all obtain with described The optimal path taken forwards；

When switch queue length more than or equal to threshold value length also, less than maximum allowable queue length and The ingress rate of switch more than leave speed time, withProbability packet loss, remaining UDP Packet forwards with the optimal path of described acquisition；

When the queue length of switch is more than its maximum allowable queue length, the described switch of all entrance UDP message bag all will be dropped.

Wherein it is desired to be understood by controller can generate corresponding stream table list item, stream table list item is by under controller Issuing respective switch, stream table list item comprises three parts: head, enumerator and action, switch is direct The header information of matched data stream, matches and directly performs corresponding action, and this action is specially according to losing Bag probability ρ_iPacket loss.

Step 210, by described when the data stream received in corresponding switch be forwarding during UDP message stream Strategy is made as stream table list item, is sent to the switch of described correspondence.

It is to be appreciated that step 208,209, corresponding switch described in 210, refer to optimal path On switch, after each switch on path receives UDP message stream, according to stream table list item in This switch congestion of record, and according to the drop probabilities packet loss of record；If record should in stream table list item Switch is the most congested, not packet loss；If recording this switch heavy congestion, then by complete for the packet that receives Portion abandons.

By the step 208 of above-mentioned increase, step 209, step 210 so that this controller can be to friendship The UDP message stream changed planes performs different forwarding strategies, i.e. with drop probabilities ρ_iStrategy forward. Enable the controller to that the different data streams in switch carries out different forwardings control.

Embodiment three

Embodiments providing and a kind of avoid congested method for routing, the method is handed over mainly for explanation Change planes and receive the stream table list item made according to forwarding strategy that controller sends, so that after switch When continued access receives data stream, the stream table list item that can inquire about storage carries out forwarding data flow.

The method includes:

Step 301, receives the stream table list item that controller sends,

Step 302, stores described stream table list item.

A kind of avoiding congested method for routing by what the present embodiment provided, the method switch receives control Device processed sends stream table list item, when switch subsequently received data stream, can inquire about the stream table table of storage Item carries out forwarding data flow.

Execute example four

Embodiments providing and a kind of avoid congested method for routing, the method is the angle from switch Degree explanation, when there being data stream to flow into switch, the stream table list item that switch sends with specific reference to controller Data stream shunts, thus is prevented effectively from congested, and the data re-transmission etc. also avoiding packet loss to bring causes net Network continues the factor deteriorated.

As it is shown in fig. 7, the method includes:

Step 401, switch receives data stream；

Step 402, according to the stream table list item of storage, is two stream compression by the data flow point of described reception Send out,

The switch of this execution the method be in optimal path source node switch to perform triage operator, road The stream table list item that footpath intermediate node then issues according to controller performs to be forwarded to the operation of down hop, does not performs The operation of shunting.

By the above-mentioned explanation to the embodiment of the present invention four, after in the program, switch receives data stream, root According to the forwarding strategy of record in stream table list item, it is two data streaming by congested data flow point, one Data stream can bear speed with original path, according to this original path transmission, another data stream of shunting Transmit with the optimal path under non-congested state.Thus the prior art packet discard avoided cause pass The problem that defeated efficiency is the best, substantially increases efficiency of transmission.

Preferably, in the data stream being split is with stream table list item, the non-congested state optimization path of record turns Before Faing, it is also possible to the data packet header at this data stream being split arranges expression (using ECN mechanism), Make the destination node receiving this packet when communicating with the source node being sent to data stream, inform this source Node sends streaming rate and causes the most greatly congested, and then carries out data stream adjustment at source node, thus Avoid congested.Therefore, the method can also include:

Step 403, for record in speed v of the data stream with described reception, with described stream table list item The speed of the difference of the maximum rate of influx that optimal path is allowed, another data stream of forwarding, described It (can be specifically in IP head type of service field that the data packet header of another data stream arranges sign The 6th be set to " 11 " for ECT position and the 7th CE position, wherein, use ECT position and CE position to set The scheme put is mainly based upon ECN mechanism, and ECN is the standard that IETF working group proposes, and generally acknowledges at present Congestion notification method, certainly, the present embodiment is not intended to use the situation of the setting of), for district Point this data stream is the data stream of congested shunting.

Preferably, above-mentioned steps 402 can also include:

If the described optimal path of record is not in congestion state, according to described stream in described stream table list item In table list item, the optimal path of record forwards described data stream.

Preferably, based on controller side, UDP message stream and tcp data stream are issued different stream tables respectively List item, therefore, for exchanger side, after step 402, the method also includes:

Step 404, it is judged that whether the data stream of described reception is tcp data stream,

If tcp data stream, perform step 403, according to the stream table list item of storage, by described reception Data flow point be two forwarding data flows.

Step 405, when the data stream judging described reception is not tcp data stream, according to described stream table In list item, the drop probabilities of record performs forwarding, specifically includes:

When in described switch, the queue length of packet is more than or equal to threshold value length, and less than maximum Allow queue length；And the ingress rate of described switch is more than when leaving speed, with's Probability packet loss, remaining UDP message bag forwards with the optimal path of record in stream table list item；Wherein, λ_i、 u_iRespectively enter and leave the streaming rate of switch i, ρ_iDrop probabilities for switch i；

By the step 404～405 of above-mentioned increase so that switch copes with different data stream to carry out turning Send out.

Preferably, after step 401, before step 402, the method can also include:

Step 406, it is judged that whether described data stream is registered, if registration, then performs step 402；

Step 407, if unregistered, is then sent to controller by the information of described data stream.

By increasing above-mentioned steps 406 to step 407 so that switch is more intelligent, to can not number out Report controller in time according to bag, controller process.

Embodiment five

The embodiment of the present invention provides a kind of and avoids congested method for routing, and as shown in Figure 8 a, the method includes:

Step A01, in network, each switch obtains information of neighbor nodes, according to the neighbor node letter obtained Breath generates LSA (LSA, Link-State Advertisement) message；And by LSA message It is sent to controller.

It should be noted that for dynamic network, the switch in network can be timing to control Device sends LSA message, or sends LSA message, or its during current discovery information of neighbor nodes change He sends LSA message in the case of causing network change.

Wherein, in network, each switch obtains the concrete operations of information of neighbor nodes, and it is fixed to may include that Time peripherad neighbor node send Hello bag, obtain information of neighbor nodes, switch measure self with often The link overhead (such as time delay, bandwidth etc.) of individual neighbor node communication, by the information structure of the neighbor node of collection Cause LSA message to be uploaded to controller, controller construct the overall situation according to the LSA message of each switch Network topological diagram.As it is shown in figure 9, each switch is sent to the LSB message simplified schematic diagram of controller, should Figure is only easy for the explanation understood, the not restriction to the embodiment of the present invention.As shown in Figure 9, each In the LSA message that switch sends, have recorded the information of each neighbours of this switch.

Step B02, controller receive each switch sends in network LSA (LSA, Link-State Advertisement)；Controller, according to the LSA received, constructs overall network topology figure；

Step A03, in network, each switch obtains congestion state bulletin (NCA, Node Congestion Advertisement) message, wherein, NCA message is used for showing whether this switch is in congestion state. The disposal ability of each switch is limited, when certain switch in network is already at congestion state, as Fruit now exceedes its speed processing data through the speed of this switch, then the congestion state of this node To deteriorate further, this programme will use P_iRepresent the congested rate matrix of node i, each friendship in network Change planes timing or when node state changes by p_iThe NCA message constituted occurs to controller, as Shown in Figure 10, NCA message, including this node ID, type of message, generate reality, and the congested speed of node i Rate matrix P_i.Global congestion speed is constructed according to the NCA message of all nodes collected for controller Matrix.

It should be noted that assume that the queue length threshold threshold value of each switch is Q_th, when switch Queue length exceedes threshold value Q_thTime, switch can be understood as being in congestion state.As shown in figure 11, In network, switch a is in congestion state, is just having two data streams to enter switch a, two data simultaneously Stream is respectively as follows: λ_a1And λ_a2, then the total quantity entering switch a is: λ_a(λ_a=λ_a1+λ_a2), in like manner, Also having two data streams to open from switch a process, the speed left is respectively as follows: μ_a1And μ_a2, then leave Total speed of switch a is μ_a(μ_a=μ_a1+μ_a2).If the speed now entering the data stream of switch a is big In speed (that is: the λ leaving switch_a>μ_a), this means that the congestion state of node will be disliked further Change, now, it would be desirable to receive the data of ability to carry out extra process, both beyond node this part Need to avoid node that congested " spilling " phenomenon occurs, while also ensure packet be not dropped and cause unnecessary Re-transmission.

P_iIt is the congested rate matrix of definition, is used for representing the congestion information of switch i, such as following formula (2) institute Show:

P_{i} = \overset{1}{[\begin{matrix} p_{1, i} \\ \cdot \\ \cdot \\ \cdot \\ p_{j, i} \\ \cdot \\ \cdot \\ \cdot \\ p_{n, i} \end{matrix}]} - - - (2)

P_iBeing the two-dimensional matrix of n × 1, n represents the number of switch, p in region_j,iRepresent data stream from Switch j enters the maximum allowable ingress rate of switch i.It is to be appreciated that reality is entered from switch j Enter the ingress rate of switch i beyond the receptible scope of switch i, if continuing the most currently practical Data access, then will send congested, thus switch i notification controller be calculate after speed, I.e. controller temporarily allows access into the speed of switch i and not can exceed that p_j,i。

Wherein, in a switch, p can be obtained_j,iValue be such as following formula (3):

P_{j, i} = \{\begin{matrix} \frac{λ_{j \cdot i}}{λ_{i}} \cdot u_{i}, & λ_{i} &GreaterEqual; μ_{i}, q_{i} &GreaterEqual; Q_{th}; \\ \infty, & else; \end{matrix} - - - (3)

Wherein, λ_j,iRepresent the streaming rate entering switch i from switch j, λ_iRepresent that all entrance is handed over Changing planes the speed sum of i, value isu_iRepresent all streaming rates leaving switch i Sum, value isq_iRepresent the queue length of switch, work as q_iMore than switch length Threshold value Q_th, simultaneously enter the speed of switch i again more than the speed left, then mean switch The congestion state of i will deteriorate further, all maximum rates now allowing to enter switch i from switch j ForFor remainingData stream need to carry out shunting process.If now Switch is not on congestion state or enters the flow velocity of switch less than the speed left, then, institute Some data stream all will be walked according to normal routed path.

Step B04, controller receives the NCA message that in network, switch sends, and constructs global congestion speed Rate matrix, following formula is shown in (4),

P=[P₁ ... P_i ... P_n] (4)

Step B05, controller, according to overall network topology figure and global congestion rate matrix, obtains each joint Point goes to the maximum rate of influx that in network, the optimal path of other nodes and this path are allowed, and obtains Negated congested optimal path, thus construct the forwarding strategy of each node.

It should be noted that the detailed step of step B05 may include that

Step B0500: the LSA message that controller is uploaded according to each switch, constructs global network and opens up Flutter figure, then use dijkstra's algorithm to calculate each switch optimal path to other switchesS is the access switch that data stream enters Local Area Network, and D is to leave Local Area Network Telephone net node, k_iFor the telephone net node of process in the middle of every paths.

It is to be appreciated that the present embodiment is not limited to above-mentioned Dijkstra about the algorithm calculating optimal path Algorithm, it is also possible to be that other can calculate the algorithm of optimal path, should not be construed this herein The restriction of bright embodiment.

Step B0502: controller inquiry global congestion rate matrix P obtains outbound pathOn The maximum rate allowed to flow through is

p = Min (p_{S, k_{1}}, . . ., p_{k_{i - 1}, k_{i}}, . . ., p_{k_{n - 1}, k_{n}}, p_{k_{n}, D});

Step B0504: nodes being in congestion state all in network are removed from topological diagram by controller, Constructing new network topological diagram, as shown in figure 12, controller is again with dijkstra's algorithm, according to new Network topological diagram calculates the optimal path from source node to destination node of non-congested network

L_{S, k_{1}^{'}, . . ., k_{i}^{'}, . . ., k_{n}^{'}, D}^{'};

Step B0506: controller is allowed according to the optimal path of described acquisition, described optimal path Big rate of influx, and optimal path during described non-congested, structure stream table, and it is sent to corresponding switch.

Wherein, described corresponding switch can be the source node switch of optimal path, also includes institute in network Some switches, when the source node switch that switch is not optimal path, this switch does not perform point The task of flow data stream, and it is carried out transmitting data flow to down hop.For in the present embodiment, after continue Bright switch, is primarily referred to as the source node switch of optimal path, if according to the stream of controller structure Table list item, performs streamed data stream the operation forwarded.

Controller decides whether shunting at source node switch, for switch fabric all of on this path Corresponding stream table list item also sends.The stream table list item of each switch notifies that this switch is by corresponding data Which next-hop node stream sends to.The list item of table is flowed as shown in figure 13 in the switch of source node S, right In going to the data stream of destination node D, after stream table coupling, if speed v of this data stream was less than should Maximum allowable speed p in path, then this stream list item can inform switch by this data stream according to full node net The optimal path of network topological diagram structureSend data packets to next-hop node k₁, as Really speed v of this data stream is more than maximum allowable speed p in this path, then this stream list item can inform exchange This data flow point is two sub data flows by machine, and the speed of a sub data flow is that this path allows to access Maximum rate p, the optimal path that this sub data flow is constructed according to full node network topologySend to next-hop node k₁, a remaining speed is that the sub data flow of v-p will be by Optimal path according to non-congested network topology structureSend to down hop k '₁。

Step B06, controller, according to the forwarding strategy of each node of structure, generates stream table list item, concurrently Give the switch of correspondence.

By above-mentioned steps A01, step A03 step so that each switch in network is by the LSA of self It is sent to controller with NCA, controller flows the foundation of table as structure.

Controller is by performing above-mentioned steps B02, B04, B05, B06, it is possible to according to each friendship in network Change planes the LSA sent, tectonic network topological diagram, the NCA sent according to each switch in network, structure Make global congestion rate matrix, thus according to overall network topology figure and global congestion rate matrix, obtain Each node goes to the maximum rate of influx that in network, the optimal path of other nodes and this path are allowed, And obtain non-congested optimal path, ultimately constructed go out each node forwarding strategy.This forwarding strategy Make, in the stream table list item being ultimately stored in switch, to include the optimal path of non-congested so that When data stream has just enter into network, just for beyond the data-flow computation of path access capability go out one optimum non- Congested path rather than occurring under congestion situation, is carried out shunting by switch or packet loss processes, The most both avoided network congestion, and taken full advantage of again Internet resources, improve network throughput, meanwhile, Also make to load more to equalize.

Preferably, above-mentioned steps B05, the forwarding strategy of each node gone out of controller structure, according to turning Sending out constructing tactics stream table list item, can be without the concern for data stream type, wherein, data stream type can To include: transmission control protocol (TCP, Transmission Control Protocol) data stream and user Datagram protocol (UDP, User Datagram Protocol) data stream.I.e. do not differentiate between data stream type, All carry out the operation such as above-mentioned steps B05.Further, if controller is distinguished data stream type, then the party Method also includes:

Step B07: when data stream is tcp data stream, structure is as constructed each node in step B05 Forwarding strategy；

Step B08: when data stream is UDP message stream, controller is according to overall network topology figure and the overall situation Congested rate matrix, obtains each node and goes to the optimal path of other nodes and this path in network and permitted The maximum rate of influx permitted, obtains drop probabilities ρ, and wherein, contrast probability ρ will be for receiving beyond path The packet of ability abandons according to drop probabilities, thus constructs the forwarding strategy of each node.

Wherein, the value of UDP message stream drop probabilities ρ is shown in formula (5):

ρ_{i} = \{\begin{matrix} 0, & q_{i} < Q_{th}; \\ \frac{λ_{i} - u_{i}}{λ_{i}}, & λ_{i} &GreaterEqual; μ_{i}, Q_{th} \leq q_{i} < Q_{\max}; \\ 1, & q_{i} &GreaterEqual; Q_{\max}; \end{matrix} - - - (5)

Wherein, λ_i、u_iRespectively enter and leave the streaming rate of switch i, q_iTeam for switch i Row length, Q_thFor the threshold value length of switch i, Q_maxMaximum allowable queue length for switch i. When the queue length of switch is less than threshold value length, all packets are all not dropped；Work as exchange The queue length of machine is more than or equal to threshold value length entering less than maximum allowable queue length and switch again Enter speed more than leave speed time, withProbability packet loss；When the queue length of switch is big When its maximum allowable queue length, then the UDP message bag of all entrance networks all will be dropped, and press Carry out packet loss according to probability ρ and may insure that the flow velocity entering node is less than its disposal ability.

As in step B08 when data stream is UDP message stream, controller is obtaining before forwarding strategy, also Need to get the λ that switch reports_i、u_i, i.e. enter and leave the streaming rate of switch i, thus The calculating of drop probabilities as described in step B08 can be performed.

As shown in figure 14, the list item of the stream table that step B07 and step B08 obtain, in order to realize the most of the same trade or business The differentiation of business, during newly arrived Data stream query stream table, except purpose IP address to be mated connection to be mated Type (TCP, UDP).If there being multiple data streams etc. to be treated at certain switch ports themselves, for Ensure to avoid the most as far as possible the while of UDP message stream ageing the packet loss of such business, can arrange UDP business has higher priority, and switch is by priority treatment UDP message stream so that it is use as far as possible Original shortest path.

It is to be appreciated that UDP message stream is mainly real-time class data flow, the spy of this kind of business in network Point is exactly higher to requirement of real-time, and the requirement to packet loss is more relatively low, and for abandoning Packet also will not carry out retransmission process；The data stream using Transmission Control Protocol transmission is typically mainly data class number According to stream, packet loss is typically required higher by this kind of business, more relatively low to requirement of real-time, Er Qieru Network really occurs packet loss phenomenon, all can carry out retransmission process for the packet abandoned, if such industry Frequent packet loss is flowed in business, will result in substantial amounts of data packet retransmission phenomenon, deteriorates the most further Network congestion condition, also can be traffic impacting ageing, therefore, for the Business Stream that both is different, The technical program takes different disposal method.

How below step explanation switch utilizes the stream table that controller sends, and shown in Fig. 8 b, specifically wraps Include:

Step A09, switch receives the stream table list item that controller sends.

Step A10, switch receives data stream, according to the action in stream table list item, is two by data flow point Individual sub-forwarding data flow, wherein, the speed of a sub data flow is the maximum rate p that this path allows to access, The optimal path that this sub data flow is constructed according to full node network topologySend extremely Next-hop node k₁, a remaining speed is that the sub data flow of v-p will construct according to non-congested network topology Optimal pathSend to down hop k '₁。

Step A12, in described stream table list item, the described optimal path of record is in non-congested state, then according to The optimal path of full node network topology structureSend to next-hop node k₁。

By above-mentioned steps A09～the explanation of A12, switch, according to the stream table of storage, enters at data stream During network, the stream compression beyond path access capability is moved on to the optimal path of a non-congested, meanwhile, Ensure to transmit on original optimal path without departing from the data stream of path access capability, thus by data stream It is divided into two-way, it can thus be avoided network congestion, takes full advantage of again Internet resources, improve net Network handling capacity, meanwhile, can arrive the effect of equally loaded.

Preferably, in step A11, a remaining speed is that the sub data flow of v-p will be according to non-congested The optimal path of network topology structureSend to down hop k '₁Operation before, it is also possible to Including:

Step A1100, switch, in the sub data flow that a remaining speed is v-p, will belong to this number IP head according to the packet of stream arranges the sign that expression is streamed data bag；

Wherein, IP head arranges represent it is that the sign of streamed data bag can be specifically: service at IP head In type field the 6th is set to " 11 " for ECT position and the 7th CE position；

Then step A11 specifically includes: the data stream being provided with in step A1100, according to non-congested net The optimal path of network topological structureSend to down hop k '₁。

Performing above-mentioned steps A1100 by switch, switch is by ECN territory (its in the packet of shunting In, ECN mechanism employs two, IP head, one is the 6th and cries ECT position, and one is the 7th and cries CE, these two are combined referred to as ECN territory) setting, receiving terminal receives ECN territory and is arranged to ' 11 ' The packet of (" 11 " represent the 6th and are set to 1, and the 7th is also configured as 1), it is known that network occurs in that to be gathered around Plug-like state, is then filled to be the ack msg bag notice source reduction transmission speed of ' 1 ' by ECN-Echo position Rate, thus significantly more efficient solution network congestion problem.

Preferably, before step A11, i.e. according to the action in stream table, it is two subnumbers by data flow point Before sending out according to circulation, the method can also include:

Step A13: switch judges whether the data stream type received is tcp data stream, if performing Step A11；If not tcp data stream, then perform A14；

Wherein A14: switch, according to the action in stream table, receives according to drop probabilities ρ and enters this switch In data stream.

Wherein, explanation in the computing formula of drop probabilities ρ such as formula (5):

(1), when the queue length of switch is less than threshold value length, all packets are not the most lost Abandon；

(2), it is more than or equal to threshold value length again less than maximum allowable queue when the queue length of switch The ingress rate of length and switch more than leave speed time, withProbability packet loss；

(3), when the queue length of switch is more than its maximum allowable queue length, then all entrance The UDP message bag of network all will be dropped, and carry out packet loss according to probability ρ and may insure that the flow velocity of entrance node Less than its disposal ability.

Due to, in network, UDP message stream is mainly real-time class data flow, and the feature of this kind of business is exactly right Requirement of real-time is higher, and the requirement to packet loss is more relatively low, and for the packet that abandons also Retransmission process will not be carried out；The data stream using Transmission Control Protocol transmission is typically mainly data class data flow, this Packet loss is typically required higher by class business, more relatively low to requirement of real-time, and if in network Packet loss phenomenon occurs, all can carry out retransmission process, if such Business Stream is frequent for the packet abandoned Packet loss, will result in substantial amounts of data packet retransmission phenomenon, deteriorates network congestion the most further State, also can be traffic impacting ageing, therefore, the embodiment of the present invention by increase step A13, A14, it is possible to the Business Stream different for both processes respectively, improves UDP message stream and TCP The efficiency of transmission of data stream.

Embodiment six

Embodiments providing a kind of network element, this network element can be switch, but be not limited to switch, As shown in figure 15, described network element includes: the first acquiring unit C01, the first transmitting element C02, second Acquiring unit C03, and the second transmitting element C04；

Described first acquiring unit C01, is used for obtaining information of neighbor nodes, according to the neighbor node obtained Information generates LSA LSA message；

Described first transmitting element C02, for being sent to controller by LSA message；

Described second acquisition unit C03, is used for obtaining congestion state bulletin NCA message, wherein, described NCA message includes the congestion information of described network element；

Wherein, the congestion information of described network element is specifically by the congested rate matrix P of described network element_iRepresent；

P_{i} = \overset{1}{[\begin{matrix} p_{1, i} \\ \cdot \\ \cdot \\ \cdot \\ p_{j, i} \\ \cdot \\ \cdot \\ \cdot \\ p_{n, i} \end{matrix}]}

Wherein, p_j,iValue be such as following formula:

P_{j, i} = \{\begin{matrix} \frac{λ_{j \cdot i}}{λ_{i}} \cdot u_{i}, & λ_{i} &GreaterEqual; μ_{i}, q_{i} &GreaterEqual; Q_{th}; \\ \infty, & else; \end{matrix}

Described second transmitting element C04, for being sent to described controller by described NCA message.

By a kind of network element of above-mentioned the present embodiment six explanation, in the program, the network element in network is by the neighbour of self Occupy nodal information and self congestion information, be sent to controller by LSA and NCA respectively, by controlling Each network element in network is managed collectively by device, constructs overall network topology figure, and global congestion information, makes Controller according to described overall network topology figure, obtain each node and go in network other node Shortest path；According to described global congestion information, and described optimal path, obtain described optimal path and allow Maximum rate of influx；According to described global congestion information, by joints being in congestion state all in network Point removes the network topological diagram obtaining non-congested state from topological diagram；Network according to non-congested state is opened up Flutter figure, obtain optimal path during non-congested；According to the optimal path of described acquisition, described optimal path The maximum rate of influx allowed, and optimal path during described non-congested, obtain forwarding strategy, and root Make stream table list item according to forwarding strategy, and stream table list item is sent to corresponding network element so that described network element obtains Take stream table list item, and store；Wherein, according to the optimal path of described acquisition, described optimal path is permitted The maximum rate of influx permitted, and optimal path during described non-congested, obtain forwarding strategy, specifically include:

When speed v of the data stream received in described corresponding network element is allowed more than described optimal path Big rate of influx, then be two data streams by the data flow point of described reception, wherein, data stream with Speed is the maximum rate of influx that described optimal path allows, and forwards according to the optimal path of described acquisition； Another data stream is with speed v of the data stream of described reception, the maximum allowed with described optimal path The speed of the difference of rate of influx, forwards according to optimal path during described non-congested.

Therefore, the technical scheme that this example demonstrates that, compared with prior art, it is to avoid such as letter in tail dropping algorithm Single abandons the packet exceeding queue max threshold length, just also overcomes when network does not occurs congested Start the problem that packet loss can cause the waste of Internet resources in advance, it is provided that one is more reasonably avoided congested Method, thus ensure the quality that data are transmitted, provide the user the service of higher efficiency.

Embodiment seven

The embodiment of the present invention provides a kind of controller, and as shown in figure 16, described controller includes:

First receives cells D 01, the first structural unit D02, and second receives cells D 03, and the 3rd obtains Cells D 04, the 4th acquiring unit D05, the 5th acquiring unit D06, the 6th acquiring unit D07, the 7th Acquiring unit D08, the 3rd transmitting element D09；

Described first receives cells D 01, for receiving the LSA message that in network, each network element sends；

Described first structural unit D02, for according to described LSA message, constructs overall network topology Figure；

Described second receives cells D 03, for receiving the NCA message that in network, each network element sends；

Described 3rd acquiring unit D04, for according to described NCA message, obtains global congestion information；

Described 4th acquiring unit D05, for according to described overall network topology figure, obtains each node and goes The optimal path of other node in network；

Described 5th acquiring unit D06, is used for according to described global congestion information, and described optimal path, Obtain the maximum rate of influx that described optimal path allows；

Described 6th acquiring unit D07, for according to described global congestion information, by places all in network Node in congestion state removes the network topological diagram obtaining non-congested state from topological diagram；Gather around according to non- The network topological diagram of plug-like state, obtains optimal path during non-congested；

Described 7th acquiring unit D08, for the optimal path according to described acquisition, described optimal path institute The maximum rate of influx allowed, and optimal path during described non-congested, obtain forwarding strategy；

Wherein, according to the optimal path of described acquisition, the maximum rate of influx that described optimal path is allowed, With optimal path during described non-congested, obtain forwarding strategy, specifically include:

If when optimal path there being network element be in congestion state, it is desirable to the source node net of described optimal path The data flow point of described reception is two data streams by unit, wherein, data stream with speed be described The maximum rate of influx that shortest path allows, forwards according to the optimal path of described acquisition；Another data stream With speed v of the data stream of described reception, with the difference of the maximum rate of influx that described optimal path is allowed Speed, according to during described non-congested optimal path forward；

Described 3rd transmitting element D09, for the forwarding strategy of described acquisition is sent to corresponding network element, makes Obtain described network element and obtain stream table list item according to described forwarding strategy, and store.

By the above-mentioned explanation to the embodiment of the present invention seven, program middle controller is according to net each from network Unit obtains LSA message and NCA message, constructs overall network topology figure and global congestion information, according to Overall network topology figure and global congestion information, construct the network element two paths under being in congestion state, Data flow point that will be congested is two data streaming, and a data stream can bear speed with original path, According to this original path transmission, another data stream of shunting transmits with the optimal path under non-congested state. Thus the prior art packet discard avoided cause the best problem of efficiency of transmission, substantially increase biography Defeated efficiency.

Preferably, for the optimal path according to described acquisition in described 7th acquiring unit D08, described The maximum rate of influx that optimal path is allowed, and optimal path during described non-congested, obtain and forward plan Slightly, also specifically include:

When speed v of the data stream received in the source node network element of optimal path is less than described optimal path institute The maximum rate of influx allowed, the max-flow that described data stream is allowed by described optimal path with speed Enter speed, forward according to the optimal path of described acquisition.

Preferably, each NCA message received in the second reception cells D 03 includes gathering around of a network element Plug information, the congestion information of described network element is specifically by the congested rate matrix P of described network element_iRepresent；

P_{i} = \overset{1}{[\begin{matrix} p_{1, i} \\ \cdot \\ \cdot \\ \cdot \\ p_{j, i} \\ \cdot \\ \cdot \\ \cdot \\ p_{n, i} \end{matrix}]}

Wherein, p_j,iValue be such as following formula:

P_{j, i} = \{\begin{matrix} \frac{λ_{j \cdot i}}{λ_{i}} \cdot u_{i}, & λ_{i} &GreaterEqual; μ_{i}, q_{i} &GreaterEqual; Q_{th}; \\ \infty, & else; \end{matrix}

Wherein, λ_j,iRepresent the streaming rate entering network element i from network element j；λ_iRepresent all entrance network element i's Speed sum, value isu_iRepresent all streaming rate sums leaving network element i, take Value isq_iRepresent the queue length of network element, work as λ_i≥μ_i, and q_iMore than or equal to network element length Threshold value Q_thTime, described network element is in congestion state；

According to the congestion information of the network element that described NCA message includes, construct global congestion rate matrix P, it may be assumed that

P=[P₁ ... P_i ... P_n]

Wherein, n represents the number of network element, P in region_iCongested rate matrix for described network element.

Preferably, in described 5th acquiring unit D06, it is used for according to described global congestion information, and institute State optimal path, obtain the maximum rate of influx that described optimal path is allowed, specifically include:

From global congestion information and in described optimal path, obtain previous dive ki-1 in described optimal path and arrive Down hop k_iMaximum allowable ingress rate

Preferably, for the optimal path according to described acquisition in described 7th acquiring unit D08, described The maximum rate of influx that optimal path is allowed, and optimal path during described non-congested, obtain and forward plan Omit, particularly as follows:

The described optimal path according to described acquisition, the maximum rate of influx that described optimal path is allowed, and Optimal path during described non-congested, obtains when the data stream received in corresponding network element is tcp data stream Forwarding strategy.

Preferably, described controller also includes:

Described second receives unit, is additionally operable to receive the data entering and leaving each network element that each network element sends Flow velocity rate；

Second structural unit D10 and the 4th transmitting element D11；

Described second structural unit D10, is used at described 4th acquiring unit according to described overall network topology Figure, obtains each node and goes in network after the optimal path of other node, when receiving in corresponding network element Data stream when being UDP message stream, according to the described streaming rate entering and leaving each network element, structure Drop probabilities ρ_iStrategy；

Described 4th transmitting element D11, being used for the described data stream received in corresponding network element of working as is UDP Forwarding strategy during data stream is made as stream table list item, is sent to the network element of described correspondence.

Preferably, for when the data stream received in corresponding network element being in described second structural unit D10 During UDP message stream, according to the described streaming rate entering and leaving each network element, construct drop probabilities ρ_i Strategy, specifically include:

Using equation below as the drop probabilities when the data stream received in corresponding network element is for UDP message stream ρ_iStrategy:

ρ_{i} = \{\begin{matrix} 0, & q_{i} < Q_{th}; \\ \frac{λ_{i} - u_{i}}{λ_{i}}, & λ_{i} &GreaterEqual; μ_{i}, Q_{th} \leq q_{i} < Q_{\max}; \\ 1, & q_{i} &GreaterEqual; Q_{\max}; \end{matrix}

Wherein, λ_i、u_iIt is respectively the streaming rate entering and leaving network element i of reported by network elements, q_iFor net The queue length of unit i, Q_thFor the threshold value length of network element i, Q_maxMaximum allowable queue for network element i is long Degree；

Described according to described drop probabilities ρ_iStrategy, and the optimal path of described acquisition, obtain when corresponding net The data stream received in unit is forwarding strategy during UDP message stream, specifically includes:

When the queue length of network element is less than threshold value length, all UDP message bags are all with described acquisition Optimal path forward；

When the queue length of network element is more than or equal to threshold value length also, less than maximum allowable queue length and net Unit ingress rate more than leave speed time, withProbability packet loss, remaining UDP number Forward with the optimal path of described acquisition according to bag；

Embodiment eight

Embodiments providing a kind of network element, described network element includes: the 3rd receives unit, and storage Unit；

Described 3rd receives unit, for receiving the stream table list item that controller sends,

Described memory element, is used for storing described stream table list item.

The network element provided by the present embodiment, receives the stream table list item that controller sends, so that net During the subsequently received data stream of unit, the stream table list item that can inquire about storage carries out forwarding data flow.

Embodiment nine

Embodiments providing a kind of network element, this network element can be switch, but be not limited to switch. As shown in figure 17, described network element includes: the 4th receives unit E01, and the first retransmission unit E03；

Described 4th receives unit E01, is used for receiving data stream；

Described first retransmission unit E03, for the stream table list item according to storage, by the data stream of described reception It is divided into two forwarding data flows；Wherein, a data stream is to record in described stream table list item with speed The maximum rate of influx that shortest path allows, forwards according to the optimal path of record in described stream table list item；Separately One data stream is with the optimal path of record in speed v of the data stream of described reception, with described stream table list item The speed of the difference of the maximum rate of influx allowed, according in described stream table list item record non-congested time Optimal path forwards.

By above-mentioned to embodiment of the present invention explanation just, after in the program, network element receives data stream, according to In stream table list item, the forwarding strategy of record, is two data streaming by congested data flow point, a number Speed can be born according to stream with original path, according to this original path transmission, another data stream of shunting with Optimal path transmission under non-congested state.Thus the prior art packet discard avoided cause transmission The problem that efficiency is the best, substantially increases efficiency of transmission.

Preferably, described network element also includes: indicate unit E04,

Described sign unit E04, records according to described stream table list item for described first retransmission unit Before optimal path during non-congested forwards, for speed v of the data stream with described reception, with described stream The speed of the difference of maximum rate of influx that the optimal path of record is allowed in table list item, another of forwarding Data stream, the data packet header at another data stream described arranges sign, is used for distinguishing this data stream and is The data stream of congested shunting.

Preferably, described network element, also include: the second retransmission unit E05,

Described second retransmission unit E05, if the described optimal path of record is in described stream table list item Non-congested state, forwards described data stream according to the optimal path of record in described stream table list item.

Preferably, described network element, also include: the second judging unit E06,

Described second judging unit E06, for described first retransmission unit according to the stream table list item stored, will Before the data flow point of described reception is two forwarding data flows, it is judged that whether the data stream of described reception is Tcp data stream；

Preferably, described network element also includes: the 3rd retransmission unit E07,

Described 3rd retransmission unit E07, is not tcp data stream for working as the data stream judging described reception Time, perform forwarding according to record in described stream table list item, specifically include:

When in described network element, the queue length of packet is more than or equal to threshold value length and fair less than maximum Permitted queue length；And the ingress rate of described network element is more than when leaving speed, withProbability Packet loss, remaining UDP message bag forwards with the optimal path of record in stream table list item；Wherein, λ_i、u_i Respectively enter and leave the streaming rate of network element i, ρ_iDrop probabilities for network element i；

Preferably, described network element also includes: the 3rd judging unit E08, and the 5th transmitting element E09；

Described 3rd judging unit, after described 4th reception unit receives data stream, described first Before judging unit judges whether described network element is in congestion state, it is judged that whether described data stream is registered；

If registration, then notify that described first judging unit performs that described to judge whether described network element is in congested The operation of state；

Described 5th transmitting element, if for unregistered, being sent to controller by the information of described data stream.

Embodiment ten

Embodiments providing a kind of network element, this network element can be switch, but be not limited to switch, As shown in figure 18, including the memorizer 40 being connected respectively in bus, processor 41, input equipment 43 and Output device 44, wherein:

Memorizer 40 is used for store the data from input equipment 43 input, and processor 41 can also be stored The information such as the necessary file of process data；

Preferably, the congestion information of described network element is specifically by the congested rate matrix P of described network element_iRepresent；

P_{i} = \overset{1}{[\begin{matrix} p_{1, i} \\ \cdot \\ \cdot \\ \cdot \\ p_{j, i} \\ \cdot \\ \cdot \\ \cdot \\ p_{n, i} \end{matrix}]}

Wherein, p_j,iValue be such as following formula:

P_{j, i} = \{\begin{matrix} \frac{λ_{j \cdot i}}{λ_{i}} \cdot u_{i}, & λ_{i} &GreaterEqual; μ_{i}, q_{i} &GreaterEqual; Q_{th}; \\ \infty, & else; \end{matrix}

Preferably, described output device, it is additionally operable to be transmitted into and leave the streaming rate of described network element Numerical value, described in enter and leave the numerical value of streaming rate of described network element, obtain in controller Structure drop probabilities ρ when data stream is UDP message stream_iStrategy.

By the above-mentioned a kind of network element that this example demonstrates that, in the program, the network element in network is by the neighbours of self Nodal information and self congestion information, be sent to controller by LSA and NCA, respectively by controller Each network element in network is managed collectively, constructs overall network topology figure, and global congestion information so that Controller, according to described overall network topology figure, obtains each node and goes to the optimum of other node in network Path；According to described global congestion information, and described optimal path, obtain what described optimal path allowed Maximum rate of influx；According to described global congestion information, by nodes being in congestion state all in network The network topological diagram obtaining non-congested state is removed from topological diagram；Network topology according to non-congested state Figure, obtains optimal path during non-congested；According to the optimal path of described acquisition, described optimal path institute The maximum rate of influx allowed, and optimal path during described non-congested, acquisition forwarding strategy, and according to Forwarding strategy makes stream table list item, and stream table list item is sent to corresponding network element so that described network element obtains Stream table list item, and store；Wherein, according to the optimal path of described acquisition, described optimal path is allowed Maximum rate of influx, and optimal path during described non-congested, obtain forwarding strategy, specifically include:

Embodiment 11

The embodiment of the present invention provides a kind of controller, as shown in figure 19, including being connected respectively in bus Memorizer 50, processor 51, input equipment 53 and output device 54, wherein:

Memorizer 50 is used for store the data from input equipment 53 input, and processor 41 can also be stored The information such as the necessary file of process data；

Described input equipment 53, for receiving the LSA message that in network, each first network element sends；Receive net The NCA message that in network, each first network element sends；

Described processor 51, for according to described LSA message, constructs overall network topology figure；According to Described NCA message, obtains global congestion information；According to described overall network topology figure, obtain each Node goes to the optimal path of other node in network；According to described global congestion information, and described acquisition Optimal path, obtain described acquisition optimal path allow maximum rate of influx；According to the described overall situation Nodes being in congestion state all in network are removed from topological diagram and are obtained non-congested shape by congestion information The network topological diagram of state；According to the network topological diagram of non-congested state, obtain optimal path during non-congested； According to the optimal path of described acquisition, the maximum rate of influx that the optimal path of described acquisition is allowed, and Optimal path during described non-congested, obtains forwarding strategy, obtains stream table list item according to described forwarding strategy；

Described output device 54, for being sent to described first network element by the described stream table list item obtained.

Preferably, for the optimal path according to described acquisition, the optimum road of described acquisition in described processor The maximum rate of influx that footpath is allowed, and optimal path during described non-congested, obtain forwarding strategy, also Specifically include:

Preferably, each NCA message received in described input equipment includes gathering around of first network element Plug information, the congestion information of described first network element is specifically by the congested rate matrix P of described first network element_iTable Show；

P_{i} = \overset{1}{[\begin{matrix} p_{1, i} \\ \cdot \\ \cdot \\ \cdot \\ p_{j, i} \\ \cdot \\ \cdot \\ \cdot \\ p_{n, i} \end{matrix}]}

Wherein, p_j,iValue be such as following formula:

P_{j, i} = \{\begin{matrix} \frac{λ_{j \cdot i}}{λ_{i}} \cdot u_{i}, & λ_{i} &GreaterEqual; μ_{i}, q_{i} &GreaterEqual; Q_{th}; \\ \infty, & else; \end{matrix}

P=[P₁ ... P_i ... P_n]

Preferably, in described processor, for according to described global congestion information, and described acquisition is Shortest path, obtains the maximum rate of influx that the optimal path of described acquisition is allowed, specifically includes:

Preferably, for the optimal path according to described acquisition, the optimum of described acquisition in described processor The maximum rate of influx that path is allowed, and optimal path during described non-congested, obtain forwarding strategy, Particularly as follows:

Preferably, described input equipment, it is additionally operable to receive that each first network element sends enters and leaves each the The streaming rate of one network element；

Described processor is additionally operable to:

Preferably, being used for the data stream when receiving in corresponding first network element in described processor is UDP message During stream, according to the described streaming rate entering and leaving each first network element, construct drop probabilities ρ_iPlan Slightly, specifically include:

ρ_{i} = \{\begin{matrix} 0, & q_{i} < Q_{th}; \\ \frac{λ_{i} - u_{i}}{λ_{i}}, & λ_{i} &GreaterEqual; μ_{i}, Q_{th} \leq q_{i} < Q_{\max}; \\ 1, & q_{i} &GreaterEqual; Q_{\max}; \end{matrix}

By the above-mentioned explanation to the embodiment of the present invention, program middle controller obtains according to network element each from network Take LSA message and NCA message, construct overall network topology figure and global congestion information, according to entirely Office network topological diagram and global congestion information, construct the network element two paths under being in congestion state, Data flow point that will be congested is two data streaming, and a data stream can bear speed with original path, According to this original path transmission, another data stream of shunting transmits with the optimal path under non-congested state. Thus the prior art packet discard avoided cause the best problem of efficiency of transmission, substantially increase biography Defeated efficiency.

Embodiment 12

Embodiments providing a kind of network element, this network element can be switch, but be not limited to switch. As shown in figure 20, including the memorizer 60 being connected respectively in bus, processor 61, input equipment 63 and Output device 64, wherein:

Memorizer 60 is used for store the data from input equipment 63 input, and processor 61 can also be stored The information such as the necessary file of process data；

Described input equipment 63, is used for receiving data stream；

Described processor 61, for the stream table list item according to storage, is two by the data flow point of described reception Prop up forwarding data flow；Wherein, a data stream is the optimal path of record in described stream table list item with speed The maximum rate of influx allowed, forwards according to the optimal path of record in described stream table list item；Another number According to stream with speed v of the data stream of described reception, allowed with the optimal path of record in described stream table list item The speed of difference of maximum rate of influx, according to optimum road during the non-congested of record in described stream table list item Footpath forwards.

Preferably, described processor, it is additionally operable to described first retransmission unit according in described stream table list item Before optimal path during the non-congested of record forwards, for speed v of the data stream with described reception, with The speed of the difference of the maximum rate of influx that the optimal path of record is allowed in described stream table list item, forwarding Another data stream, the data packet header at another data stream described arranges sign, is used for distinguishing this number It is the data stream of congested shunting according to stream.

Preferably, described processor, if being additionally operable in described stream table list item at the described optimal path of record In non-congested state, forward described data stream according to the optimal path of record in described stream table list item.

Preferably, described processor, it is additionally operable at described first retransmission unit according to the stream table list item stored, Before the data flow point of described reception is two forwarding data flows, it is judged that whether the data stream of described reception For tcp data stream；

Preferably, described processor, it is additionally operable to when the data stream judging described reception is not tcp data stream Time, perform forwarding according to record in described stream table list item, specifically include:

One of ordinary skill in the art will appreciate that all or part of step in the various methods of above-described embodiment Suddenly the program that can be by completes to instruct relevant hardware, and this program can be stored in a computer can Reading in storage medium, storage medium may include that ROM, RAM, disk or CD etc..

Thered is provided the embodiment of the present invention above a kind of avoids congested method for routing and device, carries out Being discussed in detail, principle and the embodiment of the present invention are set forth by specific case used herein, The explanation of above example is only intended to help to understand method and the core concept thereof of the present invention；Meanwhile, right In one of ordinary skill in the art, according to the thought of the present invention, in detailed description of the invention and range of application On all will change, in sum, this specification content should not be construed as limitation of the present invention.

Claims

1. avoid congested method for routing for one kind, it is characterised in that including:

Described first network element obtains congestion state bulletin NCA message, and described NCA message is sent to institute State controller, wherein, described NCA message includes the congestion information of described first network element；

Wherein, the congestion information of described first network element is specifically by the congested rate matrix P of described first network element_iTable Show；

Wherein, p_j,iValue be such as following formula:

p_{j, i} = \{\begin{matrix} \frac{λ_{j . i}}{λ_{i}} \cdot u_{i}, & λ_{i} &GreaterEqual; μ_{i}, q_{i} &GreaterEqual; Q_{t h}; \\ \infty, & e l s e; \end{matrix}

Wherein, λ_j,iRepresent the streaming rate entering the first network element i from the first network element j；λ_iRepresent all enter Entering the speed sum of the first network element i, value isu_iRepresent all and leave the first network element i's Streaming rate sum, value isq_iRepresent the queue length of the first network element, work as λ_i≥μ_i, And q_iThreshold value Q more than or equal to the first network element length_thTime, described first network element is in congestion state.

Method the most according to claim 1, it is characterised in that described method also includes:

3. avoid congested method for routing for one kind, it is characterised in that including:

According to described global congestion information, and the optimal path of described acquisition, obtain the optimum road of described acquisition The maximum rate of influx that footpath allows；

If when the optimal path of described acquisition there being the first network element be in congestion state, it is desirable to described acquisition Source node first network element of optimal path be two data streams, wherein, one by the data flow point of reception The maximum rate of influx that data stream allows with the optimal path that speed is described acquisition, according to described acquisition Optimal path forwards；Another data stream is with speed v of the data stream of described reception, with described acquisition The speed of the difference of the maximum rate of influx that optimal path is allowed, according to optimal path during described non-congested Forward.

Method the most according to claim 3, it is characterised in that according to the optimal path of described acquisition, The maximum rate of influx that the optimal path of described acquisition is allowed, and optimal path during described non-congested, Obtain forwarding strategy, also specifically include:

5. according to method described in claim 3 or 4, it is characterised in that each NCA message wraps Including the congestion information of first network element, the congestion information of described first network element is specifically by described first network element Congested rate matrix P_iRepresent；

Wherein, p_j,iValue be such as following formula:

p_{j, i} = \{\begin{matrix} \frac{λ_{j . i}}{λ_{i}} \cdot u_{i}, & λ_{i} &GreaterEqual; μ_{i}, q_{i} &GreaterEqual; Q_{t h}; \\ \infty, & e l s e; \end{matrix}

P=[P₁ … P_i … P_n]

Method the most according to claim 5, it is characterised in that described according to described global congestion information, With the optimal path of described acquisition, obtain the maximum rate of influx that the optimal path of described acquisition is allowed, Specifically include:

Method the most according to claim 6, it is characterised in that described according to the optimal path obtained, The maximum rate of influx that the optimal path of described acquisition is allowed, and optimal path during described non-congested, Obtain forwarding strategy, particularly as follows:

Method the most according to claim 3, it is characterised in that described method also includes:

Method the most according to claim 8, it is characterised in that described when reception in the first network element When data stream is UDP message stream, according to the described streaming rate entering and leaving each first network element, structure Make drop probabilities ρ_iStrategy, specifically include:

ρ_{i} = \{\begin{matrix} 0, & q_{i} < Q_{t h}; \\ \frac{λ_{i} - u_{i}}{λ_{i}}, & λ_{i} &GreaterEqual; μ_{i}, Q_{t h} \leq q_{i} < Q_{m a x}; \\ 1, & q_{i} &GreaterEqual; Q_{\max}; \end{matrix}

When the queue length of the first network element is more than or equal to threshold value length and less than maximum allowable queue length, And first network element ingress rate more than leave speed time, withProbability packet loss, remaining UDP message bag forwards with the optimal path of described acquisition；

10. avoid congested method for routing for one kind, it is characterised in that including:

11. methods according to claim 10, it is characterised in that another data stream described is with described The maximum inflow that in speed v of the data stream received, with described stream table list item, the optimal path of record is allowed The speed of the difference of speed, forwards according to the optimal path during non-congested recorded in described stream table list item, it Before, described method also includes:

12. methods according to claim 10, it is characterised in that described method also includes:

13. according to method described in any one of claim 10 to 12, it is characterised in that described basis is deposited The stream table list item of storage, before being two forwarding data flows by the data flow point of described reception, described method is also Including:

14. according to method described in claim 13, it is characterised in that described method also includes:

When in the first network element, the queue length of packet is more than or equal to threshold value length and fair less than maximum Permitted queue length, and the ingress rate of described first network element is more than when being left speed, with ρ_iProbability packet loss, Remaining UDP message bag forwards with the optimal path of record in stream table list item；Wherein, ρ_iFor described stream table List item records the drop probabilities of the first network element i；

15. 1 kinds of network elements, it is characterised in that described network element includes: the first acquiring unit, first sends Unit, second acquisition unit, and the second transmitting element；

Described second transmitting element, for being sent to described controller by described NCA message；

Wherein, P_iFor the two-dimensional matrix of n × 1, n represents the number of network element, p in region_j,iRepresent data stream Enter the maximum allowable ingress rate of network element i from network element j, wherein, network element i is to avoid congested route side The network element of method executive agent；

Wherein, p_j,iValue be such as following formula:

p_{j, i} = \{\begin{matrix} \frac{λ_{j . i}}{λ_{i}} \cdot u_{i}, & λ_{i} &GreaterEqual; μ_{i}, q_{i} &GreaterEqual; Q_{t h}; \\ \infty, & e l s e; \end{matrix}

16. according to network element described in claim 15, it is characterised in that described second transmitting element, also For being transmitted into and leave the numerical value of streaming rate of described network element, described in enter and leave described net The numerical value of the streaming rate of unit, obtains structure when data stream is UDP message stream in controller Drop probabilities ρ_iStrategy.

17. 1 kinds of controllers, it is characterised in that described controller includes:

18. according to controller described in claim 17, it is characterised in that use in described 7th acquiring unit In the optimal path according to described acquisition, the maximum rate of influx that the optimal path of described acquisition is allowed, With optimal path during described non-congested, obtain forwarding strategy, also specifically include:

19. according to controller described in claim 17, it is characterised in that second receives reception in unit Each NCA message includes the congestion information of first network element, the congestion information tool of described first network element Body is by the congested rate matrix P of described first network element_iRepresent；

Wherein, P_iFor the two-dimensional matrix of n × 1, n represents the number of the first network element, p in region_j,iRepresent number Enter the maximum allowable ingress rate of the first network element i from the first network element j according to stream, wherein, the first network element i is Avoid the first network element of congested method for routing executive agent；

Wherein, p_j,iValue be such as following formula:

p_{j, i} = \{\begin{matrix} \frac{λ_{j . i}}{λ_{i}} \cdot u_{i}, & λ_{i} &GreaterEqual; μ_{i}, q_{i} &GreaterEqual; Q_{t h}; \\ \infty, & e l s e; \end{matrix}

P=[P₁ … P_i … P_n]

20. according to controller described in claim 19, it is characterised in that in described 5th acquiring unit, For according to described global congestion information, and the optimal path of described acquisition, obtain the optimum of described acquisition The maximum rate of influx that path is allowed, specifically includes:

21. according to controller described in any one of claim 17 to 20, it is characterised in that the described 7th For the optimal path according to described acquisition in acquiring unit, the optimal path of described acquisition is allowed Big rate of influx, and optimal path during described non-congested, obtain forwarding strategy, particularly as follows:

22. according to controller described in claim 17, it is characterised in that described second receives unit, also For receiving the streaming rate entering and leaving each first network element that each first network element sends；

Described controller also includes:

Second structural unit and the 4th transmitting element；

23. according to controller described in claim 22, it is characterised in that use in described second structural unit In when the data stream received in corresponding first network element is UDP message stream, enter and leave respectively according to described The streaming rate of the first network element, constructs drop probabilities ρ_iStrategy, specifically include:

ρ_{i} = \{\begin{matrix} 0, & q_{i} < Q_{t h}; \\ \frac{λ_{i} - u_{i}}{λ_{i}}, & λ_{i} &GreaterEqual; μ_{i}, Q_{t h} \leq q_{i} < Q_{m a x}; \\ 1, & q_{i} &GreaterEqual; Q_{\max}; \end{matrix}

24. 1 kinds of network elements, it is characterised in that described network element includes: the 4th receives unit, and first turn Bill unit；

Described 4th receives unit, is used for receiving data stream；

25. according to network element described in claim 24, it is characterised in that described network element also includes: identifying sheet list Unit,

26. according to network element described in claim 24, it is characterised in that described network element, also includes: second Retransmission unit,

27. according to network element described in any one of claim 24 to 26, it is characterised in that described network element is also Including: the second judging unit,

28. according to network element described in claim 27, it is characterised in that described network element also includes: the 3rd turn Bill unit,

29. 1 kinds of network elements, it is characterised in that described network element includes the input dress being connected respectively in bus Put, output device, memorizer and processor；

Described output device, for being sent to controller by LSA message；Described NCA message is sent To described controller；

Wherein, p_j,iValue be such as following formula:

p_{j, i} = \{\begin{matrix} \frac{λ_{j . i}}{λ_{i}} \cdot u_{i}, & λ_{i} &GreaterEqual; μ_{i}, q_{i} &GreaterEqual; Q_{t h}; \\ \infty, & e l s e; \end{matrix}

30. according to network element described in claim 29, it is characterised in that described output device, is additionally operable to Be transmitted into and leave the numerical value of streaming rate of described network element, described in enter and leave described network element The numerical value of streaming rate, obtains structure packet loss when data stream is UDP message stream in controller Probability ρ_iStrategy.

31. 1 kinds of controllers, it is characterised in that it is defeated that described controller includes being connected respectively in bus Enter device, output device, memorizer and processor；

32. according to controller described in claim 31, it is characterised in that for basis in described processor The optimal path of described acquisition, the maximum rate of influx that the optimal path of described acquisition is allowed, and described Optimal path during non-congested, obtains forwarding strategy, also specifically includes:

33. according to controller described in claim 32, it is characterised in that receive in described input equipment Each NCA message includes the congestion information of first network element, the congestion information tool of described first network element Body is by the congested rate matrix P of described first network element_iRepresent；

Wherein, p_j,iValue be such as following formula:

p_{j, i} = \{\begin{matrix} \frac{λ_{j . i}}{λ_{i}} \cdot u_{i}, & λ_{i} &GreaterEqual; μ_{i}, q_{i} &GreaterEqual; Q_{t h}; \\ \infty, & e l s e; \end{matrix}

P=[P₁ … P_i … P_n]

34. according to controller described in claim 33, it is characterised in that in described processor, for root According to described global congestion information, and the optimal path of described acquisition, obtain the optimal path institute of described acquisition The maximum rate of influx allowed, specifically includes:

35. according to controller described in any one of claim 31 to 34, it is characterised in that described process For the optimal path according to described acquisition in device, the maximum inflow that the optimal path of described acquisition is allowed Speed, and optimal path during described non-congested, obtain forwarding strategy, particularly as follows:

36. according to controller described in claim 31, it is characterised in that described input equipment, is additionally operable to Receive the streaming rate entering and leaving each first network element that each first network element sends；

Described processor is additionally operable to:

37. according to controller described in claim 36, it is characterised in that for when right in described processor Answer the data stream received in the first network element when being UDP message stream, enter and leave each first net according to described The streaming rate of unit, constructs drop probabilities ρ_iStrategy, specifically include:

ρ_{i} = \{\begin{matrix} 0, & q_{i} < Q_{t h}; \\ \frac{λ_{i} - u_{i}}{λ_{i}}, & λ_{i} &GreaterEqual; μ_{i}, Q_{t h} \leq q_{i} < Q_{m a x}; \\ 1, & q_{i} &GreaterEqual; Q_{\max}; \end{matrix}

38. 1 kinds of network elements, it is characterised in that described network element includes the input dress being connected respectively in bus Put, output device, memorizer and processor；

Described input equipment, is used for receiving data stream；

39. according to network element described in claim 38, it is characterised in that described processor, is additionally operable to first Before optimal path during the non-congested that retransmission unit records according to described stream table list item forwards, for Allowed with the optimal path of record in speed v of the data stream of described reception, with described stream table list item The speed of the difference of big rate of influx, another data stream of forwarding, in the data of another data stream described Packet header arranges sign, for distinguishing the data stream that this data stream is congested shunting.

40. according to network element described in claim 39, it is characterised in that described processor, if being additionally operable to institute State the described optimal path of record in stream table list item and be in non-congested state, remember according in described stream table list item The optimal path of record forwards described data stream.

41. according to network element described in any one of claim 38 to 40, it is characterised in that described processor, It is additionally operable at the first retransmission unit according to the stream table list item stored, is two by the data flow point of described reception Before forwarding data flow, it is judged that whether the data stream of described reception is tcp data stream；

42. according to network element described in claim 41, it is characterised in that described processor, is additionally operable to when sentencing When the data stream of disconnected described reception is not tcp data stream, perform forwarding according to record in described stream table list item, Specifically include: