CN108199959B - Load sensing energy efficiency routing method based on frequency spectrum reservation in elastic optical network - Google Patents

Load sensing energy efficiency routing method based on frequency spectrum reservation in elastic optical network Download PDF

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CN108199959B
CN108199959B CN201810092141.9A CN201810092141A CN108199959B CN 108199959 B CN108199959 B CN 108199959B CN 201810092141 A CN201810092141 A CN 201810092141A CN 108199959 B CN108199959 B CN 108199959B
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light path
spectrum
frequency spectrum
node
service
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CN108199959A (en
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刘焕淋
黄�俊
陈勇
郭晓金
蔚承英
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Chongqing University of Post and Telecommunications
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    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L45/00—Routing or path finding of packets in data switching networks
    • H04L45/12—Shortest path evaluation
    • H04L45/123—Evaluation of link metrics
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L45/00—Routing or path finding of packets in data switching networks
    • H04L45/14—Routing performance; Theoretical aspects
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L47/00—Traffic control in data switching networks
    • H04L47/10—Flow control; Congestion control
    • H04L47/12—Avoiding congestion; Recovering from congestion
    • H04L47/125—Avoiding congestion; Recovering from congestion by balancing the load, e.g. traffic engineering
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L47/00—Traffic control in data switching networks
    • H04L47/70—Admission control; Resource allocation
    • H04L47/72—Admission control; Resource allocation using reservation actions during connection setup
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04Q—SELECTING
    • H04Q11/00—Selecting arrangements for multiplex systems
    • H04Q11/0001—Selecting arrangements for multiplex systems using optical switching
    • H04Q11/0062—Network aspects
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04Q—SELECTING
    • H04Q11/00—Selecting arrangements for multiplex systems
    • H04Q11/0001—Selecting arrangements for multiplex systems using optical switching
    • H04Q11/0062—Network aspects
    • H04Q2011/0073—Provisions for forwarding or routing, e.g. lookup tables
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04Q—SELECTING
    • H04Q11/00—Selecting arrangements for multiplex systems
    • H04Q11/0001—Selecting arrangements for multiplex systems using optical switching
    • H04Q11/0062—Network aspects
    • H04Q2011/0086—Network resource allocation, dimensioning or optimisation
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02D—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN INFORMATION AND COMMUNICATION TECHNOLOGIES [ICT], I.E. INFORMATION AND COMMUNICATION TECHNOLOGIES AIMING AT THE REDUCTION OF THEIR OWN ENERGY USE
    • Y02D30/00—Reducing energy consumption in communication networks

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Abstract

The invention relates to a load sensing energy efficiency routing method based on frequency spectrum reservation in an elastic optical network, and belongs to the technical field of optical fiber communication. According to the method, the frequency spectrum usage of the adjacent link of the node on the shortest light path is counted according to the service request, and a node load state formula is designed according to the node frequency spectrum usage of the current light path and the average frequency spectrum usage of all nodes in the whole network. And judging the load of the shortest light path according to a node load state formula and the spectrum vacancy of the candidate light path. When the shortest light path is light load, a light path bandwidth reservation and grooming energy-saving routing method capable of sensing available frequency spectrum is designed, light paths and spectrum resources are dynamically reserved for services according to the size of the available frequency spectrum of the light paths, the success probability of service grooming is improved, and the energy consumption of the light paths is reduced; when the shortest light path is a heavy load, a light path cost formula based on light path hop count and spectrum continuity is used for designing a light path routing method with balanced load, thereby improving the successful transmission probability of the service and reducing the bandwidth blocking rate of the service.

Description

Load sensing energy efficiency routing method based on frequency spectrum reservation in elastic optical network
Technical Field
The invention belongs to the technical field of optical fiber communication, and relates to a load sensing energy efficiency routing method based on frequency spectrum reservation in an elastic optical network.
Background
Emerging network services with high-speed growth, such as video on demand, video conference, cloud computing, big data and the like, make the IP traffic show explosive growth, and the bandwidth resources of the communication network face unprecedented challenges. Optical fibers have the advantages of high capacity, high interference rejection, light weight, and the like, and thus become the main transmission medium of communication networks. In the traditional optical transmission technology, services are transmitted from a source node to a destination node, an intermediate node needs to perform optical-electrical-optical conversion in an uplink and downlink manner, and the physical loss and the network energy consumption become more and more serious along with the improvement of a transmission distance and a transmission rate except for the limitation of a bandwidth bottleneck of an electrical layer, so that the network expansibility is poor and the development requirement of a future network is difficult to meet. In order to meet the requirements of future network applications, transmission networks are developing towards full light, flexibility, scalability and energy saving. In the traditional Wavelength Division Multiplexing (WDM) technology, a plurality of Wavelength channels are carried on one optical fiber by frequency division multiplexing, which greatly improves the network bandwidth capacity. However, with diversification of service types and sizes, the wavelength allocation method of the fixed grid is lack of flexibility and has the disadvantage of low spectrum utilization rate, thereby limiting the rapid development of the optical network. Elastic Optical Networks (EONs) based on Optical-Orthogonal Frequency Division Multiplexing (O-OFDM) technology can flexibly allocate the number of subcarriers according to the size of a service, and the use of a high-spectrum-efficiency modulation mode further improves the spectrum utilization rate, so that the Optical network becomes a next-generation intelligent Optical network with great potential.
The development of the elastic optical network technology attracts the attention of many scholars, and the spectrum flexibility of the elastic optical network brings many advantages and also brings new challenges. Service transmission needs to meet the constraints of spectrum consistency and continuity, and how to reasonably schedule network and node resources becomes a primary objective of research. A great deal of research focuses on how to improve the bandwidth blocking rate performance of the elastic optical network, and design of energy efficiency is neglected. However, with the explosive increase of network traffic and service and the continuous expansion of network scale, the energy consumption of the network inevitably rises sharply, so that the carbon emission accounts for the increasing proportion of the total emission of the whole world. The cost of the network is increased, and the national strategic policy of sustainable development is not facilitated, so that the method becomes a key factor for restricting the network development, and the development of the optical network with effective and flexible energy is urgent. Firstly, for the ever-increasing network users and traffic, network operators will invest more funds to expand and upgrade the network, which virtually increases the number of node devices, such as repeaters, optical amplifiers, optical cross-connects, routers and the like, thereby increasing the energy consumption of the network; secondly, uneven distribution of services will cause waste of network resources and increase of energy consumption; finally, the unreasonable service transmission mode aggravates the consumption of network resources and reduces the energy efficiency. Energy consumption in the elastic optical network mainly comes from two aspects of optical network node equipment and optical fiber links, and the research on energy-saving elastic optical network routing is very necessary for the rapid development of the network and the resource saving. However, with the increase of network load, the traditional energy-saving routing method reduces available spectrum resources, has poor bandwidth blocking rate performance, and cannot meet the requirements of users. Therefore, the elastic optical network routing method for balancing the bandwidth blocking rate and the energy consumption performance based on network load research is significant.
Disclosure of Invention
In view of this, the present invention provides a method for load sensing energy-efficient routing based on spectrum reservation in an elastic optical network, which reduces network transmission energy consumption when an optical path is under a light load; when the optical path is under heavy load, the bandwidth blocking rate is reduced.
In order to achieve the purpose, the invention provides the following technical scheme:
a load sensing energy efficiency routing method based on frequency spectrum reservation in an elastic optical network judges the use conditions of resources on a shortest light path node and a light path by adopting a node load state formula based on the frequency spectrum state of an adjacent link of the shortest light path node and the vacancy of the light path frequency spectrum, and adaptively selects different routing methods to balance transmission energy consumption and bandwidth blocking rate performance of services based on the load condition of the path, specifically comprising the following steps:
s1: considering the frequency spectrum usage degree of the node adjacent link and the shortest light path, and judging the current load state of the shortest light path according to a node load state formula of the light path;
s2: according to the light path load state judged in the step S1, if the light load state is light, selecting a light path spectrum reservation grooming energy-saving routing method for sensing available spectrum with energy consumption reduction as a main optimization target to improve the success rate of traffic grooming; and if the load is heavy load, selecting a load balancing minimum cost optical path routing method taking reduction of bandwidth blocking rate as a main optimization target, and selecting a minimum cost optical path for transmission based on an optical path cost formula.
Further, the step S1 specifically includes:
calculating the adjacent link frequency spectrum usage of each node on the shortest light path according to a node frequency spectrum usage formula, calculating the average frequency spectrum usage of adjacent links of all nodes in the whole network, and calculating the frequency spectrum vacancy on the shortest light path; comparing the node frequency spectrum usage with the average frequency spectrum usage of all nodes in the whole network, and judging whether the frequency spectrum vacancy on the shortest light path is lower than the threshold delta B of the available residual bandwidth of the light paththresholdAnd in order to prevent the network from being paralyzed due to the excessively low threshold value, according to the twenty-eight criterion, the simulation experiment verification is carried out by setting the threshold value to be 0.2, the use conditions of the shortest light path node and the frequency spectrum resource on the light path are judged according to the comparison result, and the node load state of the shortest light path is judged.
Further, the step S2 specifically includes:
if the shortest light path is judged to be light load, executing light path frequency spectrum reservation operation for the service, and comprehensively considering the port rate of the repeater, the service request rate and the idle frequency spectrum block on the light path according to the reserved frequency spectrum, optimizing the number of the reserved frequency slots and preventing the reserved light path from being blocked due to no available repeater port; meanwhile, the bandwidth waste caused by reserving too many frequency slots for the service is avoided, when the service newly establishes the optical path and fails, a service seizing mechanism is introduced to seize the reserved optical path transmission service, and the influence of the frequency spectrum reservation on the subsequent service transmission is reduced; and if the shortest light path is judged to be the heavy load, selecting a feasible modulation grade which enables the transmitter to consume the least subcarriers for each candidate light path, and selecting the minimum-cost light path to transmit the service according to a light path cost formula based on the hop number of the light path and the frequency spectrum continuity.
Further, the calculation formula of the node load state is as follows:
lsi＝nfi/NF
Figure BDA0001564005690000031
wherein ls isiIndicating the load status of node i, nfiFor the spectral usage of node i, NFAverage spectrum usage for all nodes in the entire network, when lsiWhen the value of the node I is greater than 1, indicating that the available frequency spectrum of the link around the node is less than the average available frequency spectrum of the whole network, and the using number of the repeaters of the node I exceeds the using number of the average repeaters of the network, judging the node I to be a heavy load node, otherwise, judging the node I to be a light load node; liIs the firstiThe link adjoining node i, LiIs the number of links adjacent to node i, F is the total number of frequency slots on the link, N represents the number of nodes in the entire network,
Figure BDA0001564005690000032
denotes the liAnd recording the using condition of the j-th frequency slot on the adjacent link as 1 if the frequency slot is used, otherwise, recording the using condition as 0.
Further, the optical path spectrum reservation operation is:
the remaining capacity of the transponder is considered, when the remaining capacity of the transponder is sufficient, the number of frequency slots needing to be reserved is different under the condition of considering different service transmission, the available frequency spectrum blocks meeting the service request are dynamically selected, then the size of the reserved frequency spectrum blocks is compared with the maximum service request rate, the maximum reserved frequency spectrum blocks which do not exceed the maximum service request rate are selected, and the waste of bandwidth resources excessively reserved by the frequency spectrum is reduced.
Further, the optical path cost formula is as follows:
Figure BDA0001564005690000033
Figure BDA0001564005690000034
Figure BDA0001564005690000035
wherein pi _ hop is hop number of the candidate optical path, pi _ cs is frequency spectrum continuity of the candidate optical path, β is a very small value, β is 0.0001, avoiding denominator is 0, cpFor the candidate lightpath traffic carrying capabilities,
Figure BDA0001564005690000036
the service condition of the ith frequency slot on the optical path candidate optical path p is set as 1 if the ith frequency slot is idle, otherwise, the service condition is set as 0;
Figure BDA0001564005690000041
representing the number of frequency slots contained in the maximum free spectrum block on the candidate lightpath p; b isnIs a set of idle spectrum blocks, R is a set of traffic bandwidth demand types,
Figure BDA0001564005690000042
the jth idle spectrum block bandwidth size R of the candidate light pathkThe required bandwidth size for the kth type of traffic in the set R.
The invention has the beneficial effects that: according to the invention, a node load state formula is designed to judge the node load condition according to the frequency spectrum usage degree of the adjacent link of the node on the shortest optical path. If the current optical path is in light load, an energy-saving routing method for reserving and leading the optical path bandwidth by sensing available frequency spectrum is designed, the service leading probability is increased, the use of energy consumption devices is reduced, and meanwhile, the modulation grade with the minimum energy consumption is selected to save energy. If the current optical path is in heavy load, a load balancing minimum cost optical path routing method based on optical path hop count and frequency spectrum continuity as optical path cost is provided, and the modulation grade with the least frequency spectrum consumption is selected to reduce the blocking rate.
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In order to make the object, technical scheme and beneficial effect of the invention more clear, the invention provides the following drawings for explanation:
FIG. 1 is a schematic diagram of a network topology and a shortest optical path;
FIG. 2 is a schematic diagram of the use of frequency slots on an optical fiber link;
FIG. 3 is a flowchart of a load sensing energy efficiency routing method based on spectrum reservation in an elastic optical network;
fig. 4 is a flowchart of a method for sensing reservation grooming using spectrum;
FIG. 5 is a flow chart of a load balancing minimum cost optical path routing method;
fig. 6 is a schematic diagram of an embodiment of a load balancing minimum cost optical path routing method.
Detailed Description
Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings.
When a service arrives, firstly, a Dijkstra algorithm is used for the service to calculate the shortest light path between a source node and a destination node, a node frequency spectrum use degree formula is designed according to the frequency spectrum use condition of adjacent links of the nodes on the light path, the frequency spectrum use degrees of the nodes and the whole network are calculated based on the formula, and whether the nodes on the shortest light path contain heavy load nodes is judged. If the shortest light path comprises the heavy load nodes, further calculating the frequency spectrum vacancy of the shortest light path, and if the frequency spectrum vacancy is lower than the threshold value of the residual available residual bandwidth, judging the shortest light path to be the heavy load light path; otherwise, it is a light load optical path. If the light-load optical path is adopted, the spectrum resource on the optical path is sufficient, the routing takes the optimized network energy consumption as a main performance index, and a transmission optical path is selected by an optical path bandwidth reservation and dispersion energy-saving routing method based on available spectrum sensing; if the light path is a heavy-load light path, the available frequency spectrum on the light path is insufficient, the route takes the optimized bandwidth blocking rate as a main performance index, and the light path is selected for transmission based on a load balancing minimum cost light path routing method.
The specific implementation process of the optical path bandwidth reservation grooming energy-saving routing method capable of sensing by using frequency spectrum comprises the steps of firstly, judging whether the residual capacity of a repeater of a source node and a destination node meets service transmission, if not, blocking the service, otherwise, judging whether an optical path of the source node and the destination node which are the same as a service request exists, calculating the residual capacities of the repeaters of the source node and the destination node if the existing optical path of the source node and the destination node exists, recording the smaller residual capacity of the repeater, preferably the left grooming of the service, recording the bandwidth of a larger frequency spectrum block in an adjacent idle frequency spectrum block after the left grooming of the service, comparing the recorded residual capacity of the repeater and the bandwidth of the idle frequency spectrum block with the maximum service request rate, selecting the smallest residual capacity of the repeater and the bandwidth of the idle frequency spectrum block as the optimal reserved bandwidth after the left grooming, if the left grooming cannot be carried out, reserving the optimal bandwidth of the frequency spectrum for the right grooming of the service, when the service cannot be grooming, newly establishing optical path bandwidth allocation of the rsst and the optimal bandwidth, using a First reserved hit (FF) algorithm to allocate the newly established optical path, and selecting the optimal bandwidth to allocate the optimal bandwidth when the optimal bandwidth of the next idle frequency spectrum block is selected, the optimal bandwidth of the optical path is selected, the optimal bandwidth of the newly established optical path, and.
The specific implementation process of the load balancing minimum cost optical path routing method comprises the following steps: firstly, judging whether the residual capacity of a repeater of a source-destination node meets service transmission, and if not, blocking the service; otherwise, judging whether the hop count of the candidate light path exceeds a set hop count threshold value. If the hop count threshold value is not met, selecting the next candidate light path; otherwise, calculating the physical hop count of the optical path and the frequency spectrum continuity of the optical path, calculating the cost of the optical path based on the optical path cost formula, and storing the cost to a set PcostFrom the set PcostAnd (4) selecting the optical path transmission with the minimum cost. If the minimum-cost optical path cannot meet the transmission requirement, selecting a secondary minimum-cost optical path for transmission, successfully finding a transmission optical path, selecting a modulation grade meeting the minimum spectrum consumption under the distance constraint of a modulation mode to reduce the spectrum use, and simultaneously performing spectrum allocation by using a preferred hit algorithm.
The load sensing energy efficiency routing method based on the spectrum reservation in the elastic optical network can balance the energy consumption and the bandwidth blocking rate performance, optimize the size of the reserved optical path spectrum bandwidth when the service load is light, improve the service grooming probability and reduce the use of energy consumption devices; when the service load is heavier, an optical path weight formula is designed based on the idea of load balancing, so that bottleneck links are prevented from occurring, and the network bandwidth blocking rate is reduced.
Example (b):
in the network topology shown in fig. 1, it is assumed that there are service requests r1(1,6,40Gb/s), r2(1,4,60Gb/s), and the numbers on the links are physical distances between nodes, and the numbers marked on the links 1-2 in fig. 1 indicate that the physical distance from the node 1 to the node 2 is 400 km. The shortest optical path 1(1-6) and the shortest optical path 2(1-2-4) are calculated for the services r1 and r2 respectively by the Dijkstra algorithm. With reference to this example, step 1 of the load-aware energy-efficient routing method based on spectrum reservation in the elastic optical network according to the present invention is described.
FIG. 2 is a diagram illustrating link spectrum usage of the network topology shown in FIG. 1, where each link has 16 frequency slots, each frequency slot has a size of 12.5GHz, and assuming that the threshold Δ B of the remaining bandwidth available to the optical path is Δ BthresholdIs 0.2, where the adjacent link spectrum usage of each node is calculated by equation (1), where nfiFor the spectral usage of node i, NFAverage spectrum usage, l, for all nodes of the whole networkiIs the firstiThe link adjoining node i, LiIs the number of links adjacent to node i, F is the total number of frequency slots on the link, N represents the number of nodes in the entire network,
Figure BDA0001564005690000061
denotes the liAnd recording the using condition of the j-th frequency slot on the adjacent link as 1 if the frequency slot is used, otherwise, recording the using condition as 0. According to fig. 1 and 2, the shortest optical path 1(1-6) of the service r1 passes through the node 1 and the node 6, the adjacent links of the node 1 are 1-2, 1-3 and 1-6, the shortest optical path 1(1-2-4) of the service r2 passes through the node 1, the node 2 and the node 6, the adjacent links of the node 2 are 1-2, 2-3 and 2-4, and the adjacent links of the node 4 are 2-4, 4-5 and 4-6. The number of used frequency spectrums on the adjacent links 1-2 of the node 1 is 7, the number of used frequency spectrums on the adjacent links 1-3 is 6, the number of used frequency spectrums on the adjacent links 1-6 is 13, and nf of the node 1 is calculated according to the formula (1)1The value is 8.67, and similarly, nf for node 6 can be calculated6Value 8.67, nf for node 22Value 6.67, nf for node 44The value is 6 as shown in FIG. 2. In accordance withCalculating the frequency spectrum usage degree of all nodes, and calculating the average frequency spectrum usage degree N of all nodes of the whole network according to the formula (1)FThe value was 7.11. The load states of node 1, node 2, node 4, and node 6 may be calculated based on equation (2). In the formula (2), lsiIs the load state of node i, when lsiWhen the value of the node I is greater than 1, the available frequency spectrum of the link around the node is less than the average available frequency spectrum of the whole network, the using number of the repeaters of the node I exceeds the using number of the average repeaters of the network, the node I is judged to be a heavy load node, and otherwise, the node I is judged to be a light load node. The nodes 1 and 6 which are obtained by calculation are heavy-load nodes, and the nodes 2 and 4 are light-load nodes.
Figure BDA0001564005690000062
lsi＝nfi/NF(2)
In order to further evaluate the optical path load state, the spectrum usage of the optical path needs to be calculated, and the optical path spectrum vacancy is characterized by formula (3). In the formula (3), the first and second groups,
Figure BDA0001564005690000063
and
Figure BDA0001564005690000064
respectively representing the total continuous idle frequency spectrum bandwidth size on the optical path and the total frequency spectrum bandwidth size of the optical path.
Figure BDA0001564005690000065
According to the figure 2 and the formula (3), the spectrum vacancy of the optical paths 1(1-6) and the optical paths 2(1-2-4) can be calculated
Figure BDA0001564005690000066
The values are respectively 0.19 and 0.44, and the optical path 1 frequency spectrum idle value is less than the optical path available residual bandwidth threshold Delta BthresholdThe optical paths (1-6) are judged as heavy-load optical paths, a transmission route is selected by executing a load balancing minimum cost optical path routing method, and the optical paths2, the spectrum vacancy value is larger than the threshold delta B of the available residual bandwidth of the optical paththresholdAnd the optical path (1-2-4) is judged to be a light load optical path, and the transmission route is selected by executing the optical path bandwidth reservation and grooming energy-saving routing method capable of sensing the available frequency spectrum.
The following describes the load sensing energy efficiency routing method based on spectrum reservation in the elastic optical network in more detail with reference to fig. 3, and the specific process can be divided into the following steps:
s1: inputting: network topology G (V, E), where V is a set of network nodes and E is a set of links, service request ri (S, d, br), goes to S2;
s2: releasing network resources: when the service leaves from the network, releasing the frequency spectrum and the port resource of the repeater occupied by the service, and switching to S3;
s3: calculating the shortest light path for the service by using a Dijkstra algorithm, storing the nodes on the shortest light path into a set N _ P, and turning to S4;
s4: calculating the contiguous link spectrum usage nf for each node in the set N _ P using equation (1)iAnd simultaneously calculating the average frequency spectrum usage degree N of nodes of the whole networkFGo to S5;
s5: judging whether the light path contains a heavy load node according to the formula (2), if so, judging the frequency spectrum voidage of the shortest light path
Figure BDA0001564005690000071
If the available residual bandwidth is lower than the threshold value, the optical path is judged to be a heavy load optical path, and the step is switched to S6; otherwise, the light load light path is switched to S7;
s6: the shortest light path is a heavy load light path, and a transmission route is selected by executing a load balancing minimum cost light path routing method;
s7: the shortest light path is a light load light path, and a light path bandwidth reservation and dispersion energy-saving routing method capable of sensing available frequency spectrum is executed to select a transmission route;
s8: the service leaves, S2.
The step 2 of the load sensing energy efficiency routing method based on spectrum reservation in the elastic optical network is described. The following will describe in detail the optical path bandwidth reservation grooming energy-saving routing method sensed by available frequency spectrum with reference to fig. 4, and the specific process can be divided into the following steps:
s101: inputting: available spectrum array S and reserved spectrum array SresContainer V for storing existing light pathPContainer V for preserving reserved light pathresContainer V for storing available spectrum blocksBK candidate optical paths, i is 1;
s102: judging whether the residual capacity of the source-destination repeater meets the requirement of transmission, and if so, turning to S103; otherwise, the service is blocked;
s103: traverse container VPJudging whether a light path with the same source node destination node and service request ri exists, if yes, judging whether a light path V existsiTurning to S104; otherwise, turning to S108 to newly build a light path;
s104: calculating the residual capacity C of the source-destination node repeatertx,CrxLet small denote Ctr＝min{Ctx,Crx}, calculating the light path ViBlock of spectrum available at the upper part, stored at VBPerforming the following steps;
s105: left dredging: traverse VBIf there is a spectrum block VbiSatisfies the requested bandwidth size, and VbiIs equal to ViSubtracting 1 from the initial index value, and executing left grooming operation to turn to S107; otherwise, turning to S106;
s106: and (3) dredging on the right side: traverse VBIf there is a spectrum block VbjSatisfies the requested bandwidth size, and VbjIs equal to ViAdds 1 to the last index value, and executes the right grooming operation to S107; otherwise, turning to S108 to newly build a light path;
s107: updating the reservation: calculating the light path ViAvailable spectrum block, update VB. If left thinning out, finding the tail index value of the available frequency spectrum block is equal to VbiIs reduced by 1, the size of the spectrum block n1 is recorded, and the starting index value of the available spectrum block is found to be equal to ViAdding 1 spectrum block, recording the size n2 of the spectrum block, selecting the larger spectrum block as n _ max, and recording the n _ max and the service maximum request rate b _ max and CtrComparing, selecting the smallest as the reserved size of frequency spectrum
Figure BDA0001564005690000081
Storing the light path in a container VresWill be the array SresThe current reserved frequency slot in (1) is set as occupied; (if it is a right break, the starting index value for finding an available spectrum block is equal to VbjThe size of the spectrum block n1 is recorded, and the end index value of the available spectrum block is found to be equal to ViSubtracting 1 spectrum block, recording the size n2 of the spectrum block, selecting the larger spectrum block as n _ max, and recording the n _ max and the service maximum request rate b _ max and CtrComparing, selecting the smallest as the reserved size of frequency spectrum
Figure BDA0001564005690000082
Storing the light path in a container VresWill be the array SresThe current reserved frequency slot in (1) is set as occupied);
s108: newly building an optical path: on the ith light path of the source-destination node, using FF algorithm in array SresFinding available spectrum for allocation. If the spectrum allocation is successful, S107 is carried out; otherwise, turning to S109;
s109, transmission is preempted, namely an L F algorithm is used for searching an available frequency spectrum in an array S for distribution on the ith light path of the source-destination node, if the frequency spectrum distribution is successful, S107 is carried out, otherwise, i is made to be i + 1;
s110: if i > K, blocking the service request; otherwise, the process returns to S108.
The following will describe the load balancing minimum cost optical path routing method in detail with reference to fig. 5, and the specific process may be divided into the following steps:
s201: inputting: available spectrum array S, container V for storing available spectrum blocksBK candidate optical paths, i equals 1, set of optical path costs
Figure BDA0001564005690000083
Turning to S202;
s202: judging whether the residual capacity of the source-destination node transponder meets the service transmission, if so, turning to S203; otherwise, the service is blocked;
s203: judging whether the ith candidate light path exceeds the hop threshold H of the light paththresholdIf the next candidate optical path is selected, making i equal to i + 1; otherwise, turning to S204;
s204: calculating the cost pi _ cost of the optical path i based on an optical path cost formula, and storing the cost of the optical path in the set PcostTurning to S205;
s205: if i > K, from set PcostSelecting the optical path transmission with the minimum cost; otherwise, selecting the rest light path, and turning to S203;
s206: if the transmission light path is found successfully, performing spectrum allocation by using an FF algorithm; otherwise the traffic is blocked.
To further clarify the load balancing minimum cost optical path routing method, taking fig. 6 as an example, assuming that the bandwidth remaining capacity of the service source-destination node forwarder satisfies service transmission, the source node of the service request is 1 destination node 6, and Dijkstra algorithm is adopted to calculate three candidate optical paths, which are optical path 1(1-6), optical path 2(1-3-5-6) and optical path 3 (1-2-4-6). In fig. 6, the number of network topology is the physical distance between nodes, it is assumed that the size of the service request has three types, namely 40Gb/s, 60Gb/s and 100Gb/s, the adopted modulation modes have four types, namely BPSK, QPSK, 8QAM and 16QAM, and the relationship between the modulation modes and the transmission rate is shown in table 1, as can be seen from fig. 6, the lengths of three transmission optical paths are 1400km, 1850km and 1800km, respectively, and the QPSK modulation mode can be adopted to transmit the service. The number of frequency slots required for service transmission can be calculated by formula (4):
Figure BDA0001564005690000091
wherein br represents the transmission rate of the service, the number of frequency slots required for the service is Nri，emFor spectral efficiency at a modulation level of m, BfsThe bandwidth of a single frequency slot is generally 12.5GHz, and G is a guard bandwidth, generally 1 FS.
TABLE 1 subcarrier transmission rate and maximum transmission distance under different modulation modes
Figure BDA0001564005690000092
According to the formula (4), the frequency slot numbers required by the transmission of the three services are respectively 3FS, 4FS and 5FS when the QPSK modulation mode is adopted. The service bearing capacity c of the three candidate light paths can be respectively calculated by the formula (5)pIn the formula (5) BnIs a set of idle spectrum blocks, R is a set of traffic bandwidth demand types,
Figure BDA0001564005690000097
is the bandwidth size of the jth idle frequency spectrum block on the candidate light path, RkThe required bandwidth size for the kth type of traffic in the set R. As shown in fig. 6, the number of idle spectrum blocks in the optical path 1 is 3, the number of idle spectrum blocks in the optical path 2 and the optical path 3 is also 3, the service carrying capacity of the optical path 1 is calculated according to the formula (5) to be 0.25, and the service carrying capacities of the optical path 2 and the optical path 3 are respectively 0.5 and 0.71.
Figure BDA0001564005690000093
Meanwhile, as can be seen from fig. 6, the numbers of idle frequency slots on the optical path 1, the optical path 2 and the optical path 3 are respectively 7, 7 and 11, the numbers of frequency slots contained in the maximum idle frequency spectrum block on the three optical paths are respectively 3 for the optical path 1,4 for the optical path 2 and 5 for the optical path 3. The spectral continuity pi _ cs of the three candidate lightpaths can be calculated by equation (6).
Figure BDA0001564005690000094
Figure BDA0001564005690000095
The use condition of the ith frequency slot on the optical path candidate optical path p is represented as 1 if the ith frequency slot is idle, otherwise, the use condition is represented as 0.
Figure BDA0001564005690000096
Representing the largest free spectrum block on the candidate lightpath pThe number of frequency slots contained, F, represents the total number of frequency slots of the link. From the spectral usage of each optical path in fig. 6, it can be calculated that the spectral continuity of the optical path 1 is 0.33, the spectral continuity of the optical path 2 is 0.88, and the spectral continuity of the optical path 3 is 2.46. The hop count of the optical path 1 is 1, the hop count of the optical path 2 is 3, the hop count of the optical path 3 is 3, and the candidate optical path costs can be calculated according to the formula (7) and are respectively: the path 1 cost is 3.03, the path 2 cost is 3.41, and the path 3 cost is 1.22. Therefore, when the traffic is transmitted, the optical path 3 is selected preferentially, and the optical path 1 is selected secondarily.
Figure BDA0001564005690000101
Where pi _ hop is the hop count of the candidate lightpath, pi _ cs is the spectrum continuity of the candidate lightpath, β is a very small value (β equals 0.0001), and the avoided denominator is 0.
Finally, it is noted that the above-mentioned preferred embodiments illustrate rather than limit the invention, and that, although the invention has been described in detail with reference to the above-mentioned preferred embodiments, it will be understood by those skilled in the art that various changes in form and detail may be made therein without departing from the scope of the invention as defined by the appended claims.

Claims (1)

1. A load sensing energy efficiency routing method based on spectrum reservation in an elastic optical network is characterized in that: the method comprises the following steps of judging the use conditions of shortest light path nodes and light path resources by adopting a node load state formula and light path spectrum vacancy based on the spectrum state of an adjacent link of the shortest light path nodes, and adaptively selecting different routing methods to balance transmission energy consumption and bandwidth blocking rate performance of services based on the load condition of a path, and specifically comprises the following steps:
s1: inputting: network topology G (V, E), where V is a set of network nodes and E is a set of links, service request ri (S, d, br), goes to S2;
s2: releasing network resources: when the service leaves from the network, releasing the frequency spectrum and the port resource of the repeater occupied by the service, and switching to S3;
s3: calculating the shortest light path for the service by using a Dijkstra algorithm, storing the nodes on the shortest light path into a set N _ P, and turning to S4;
s4: calculating the contiguous link spectrum usage nf for each node in the set N _ P using equation (1)iAnd simultaneously calculating the average frequency spectrum usage degree N of nodes of the whole networkFGo to S5;
s5: judging whether the light path contains a heavy load node according to the formula (2), if so, judging the frequency spectrum voidage of the shortest light path
Figure FDA0002498869190000011
If the available residual bandwidth is lower than the threshold value, the optical path is judged to be a heavy load optical path, and the step is switched to S6; otherwise, the light load light path is switched to S7;
s6: the shortest light path is a heavy load light path, and a transmission route is selected by executing a load balancing minimum cost light path routing method;
s7: the shortest light path is a light load light path, and a light path bandwidth reservation and dispersion energy-saving routing method capable of sensing available frequency spectrum is executed to select a transmission route;
s8: service leaving, go to S2;
the method for reserving the grooming energy-saving route for the optical path bandwidth sensed by the available frequency spectrum specifically comprises the following steps:
s101: inputting: available spectrum array S and reserved spectrum array SresContainer V for storing existing light pathPContainer V for preserving reserved light pathresContainer V for storing available spectrum blocksBK candidate optical paths, i is 1;
s102: judging whether the residual capacity of the source-destination repeater meets the requirement of transmission, and if so, turning to S103; otherwise, the service is blocked;
s103: traverse container VPJudging whether a light path with the same source node destination node and service request ri exists, if yes, judging whether a light path V existsiTurning to S104; otherwise, turning to S108 to newly build a light path;
s104: calculating the residual capacity C of the source-destination node repeatertx,CrxLet small denote Ctr＝min{Ctx,Crx}, calculatingLight path ViBlock of spectrum available at the upper part, stored at VBPerforming the following steps;
s105: left dredging: traverse VBIf there is a spectrum block VbiSatisfies the requested bandwidth size, and VbiIs equal to ViSubtracting 1 from the initial index value, and executing left grooming operation to turn to S107; otherwise, turning to S106;
s106: and (3) dredging on the right side: traverse VBIf there is a spectrum block VbjSatisfies the requested bandwidth size, and VbjIs equal to ViAdds 1 to the last index value, and executes the right grooming operation to S107; otherwise, turning to S108 to newly build a light path;
s107: updating the reservation: calculating the light path ViAvailable spectrum block, update VB(ii) a If left thinning out, finding the tail index value of the available frequency spectrum block is equal to VbiIs reduced by 1, the size of the spectrum block n1 is recorded, and the starting index value of the available spectrum block is found to be equal to ViAdding 1 spectrum block, recording the size n2 of the spectrum block, selecting the larger spectrum block as n _ max, and recording the n _ max and the service maximum request rate b _ max and CtrComparing, selecting the smallest as the reserved size of frequency spectrum
Figure FDA0002498869190000022
Storing the light path in a container VresWill be the array SresThe current reserved frequency slot in (1) is set as occupied; if the right break out is true, the starting index value for finding the available spectrum block is equal to VbjThe size of the spectrum block n1 is recorded, and the end index value of the available spectrum block is found to be equal to ViSubtracting 1 spectrum block, recording the size n2 of the spectrum block, selecting the larger spectrum block as n _ max, and recording the n _ max and the service maximum request rate b _ max and CtrComparing, selecting the smallest as the reserved size of frequency spectrum
Figure FDA0002498869190000023
Storing the light path in a container VresWill be the array SresThe current reserved frequency slot in (1) is set as occupied;
s108: newly building an optical path: on the ith light path of the source-destination node, using FF algorithm in array SresSearching for available frequency spectrum to allocate; if the spectrum allocation is successful, S107 is carried out; otherwise, turning to S109; the FF algorithm is a First hit First algorithm;
s109, transmission is preempted, namely an L F algorithm is used for searching an available frequency spectrum in an array S for distribution on the ith light path of the source-destination node, if the frequency spectrum distribution is successful, S107 is carried out, otherwise, the i is set as i +1, and the L F algorithm is a tail end hit L ast Fit algorithm;
s110: if i > K, blocking the service request; otherwise, returning to S108;
the specific flow of the method for routing the load balancing minimum cost optical path is divided into the following steps:
s201: inputting: available spectrum array S, container V for storing available spectrum blocksBK candidate optical paths, i equals 1, set of optical path costs
Figure FDA0002498869190000021
Turning to S202;
s202: judging whether the residual capacity of the source-destination node transponder meets the service transmission, if so, turning to S203; otherwise, the service is blocked;
s203: judging whether the ith candidate light path exceeds the hop threshold H of the light paththresholdIf the next candidate optical path is selected, making i equal to i + 1; otherwise, turning to S204;
s204: calculating the cost pi _ cost of the optical path i based on an optical path cost formula, and storing the cost of the optical path in the set PcostTurning to S205;
s205: if i > K, from set PcostSelecting the optical path transmission with the minimum cost; otherwise, selecting the rest light path, and turning to S203;
s206: if the transmission light path is found successfully, performing spectrum allocation by using an FF algorithm; otherwise, the service is blocked;
calculating the adjacent link frequency spectrum usage of each node on the shortest path according to a node frequency spectrum usage formula, calculating the average frequency spectrum usage of adjacent links of all nodes in the whole network, and calculatingThe frequency spectrum vacancy on the shortest light path; comparing the node frequency spectrum usage with the average frequency spectrum usage of all nodes in the whole network, and judging whether the frequency spectrum vacancy on the shortest light path is lower than the threshold delta B of the available residual bandwidth of the light paththresholdIn order to prevent the network from being paralyzed due to the fact that the threshold value is set to be too low, simulation experiment verification is carried out according to the twenty-eight criterion and the threshold value is set to be 0.2, the use conditions of the shortest light path node and the frequency spectrum resource on the light path are judged according to the comparison result, and the node load state of the shortest light path is judged;
if the shortest light path is judged to be light load, executing light path frequency spectrum reservation operation for the service, and comprehensively considering the port rate of the repeater, the service request rate and the idle frequency spectrum block on the light path according to the reserved frequency spectrum, optimizing the number of the reserved frequency slots and preventing the reserved light path from being blocked due to no available repeater port; meanwhile, the bandwidth waste caused by reserving too many frequency slots for the service is avoided, when the service newly establishes the optical path and fails, a service seizing mechanism is introduced to seize the reserved optical path transmission service, and the influence of the frequency spectrum reservation on the subsequent service transmission is reduced; if the shortest light path is judged to be a heavy load, selecting a feasible modulation grade which enables the transmitter to consume the least subcarriers for each candidate light path, and selecting the minimum-cost light path to transmit services according to a light path cost formula based on the hop number of the light path and the frequency spectrum continuity;
the calculation formula of the node load state is as follows:
lsi＝nfi/NF(2)
Figure FDA0002498869190000031
wherein ls isiIndicating the load status of node i, nfiFor the spectral usage of node i, NFAverage spectrum usage for all nodes in the entire network, when lsiWhen the value of the node I is greater than 1, indicating that the available frequency spectrum of the link around the node is less than the average available frequency spectrum of the whole network, and the using number of the repeaters of the node I exceeds the using number of the average repeaters of the network, judging the node I to be a heavy load node, otherwise, judging the node I to be a light load node; liIs the firstThe link adjoining node i, LiIs the number of links adjacent to node i, F is the total number of frequency slots on the link, N represents the number of nodes in the entire network,
Figure FDA0002498869190000032
denotes the liIf the frequency slot is used, the using condition of the jth frequency slot on the adjacent link is marked as 1, otherwise, the using condition is 0;
the optical path spectrum reservation operation is as follows:
the method comprises the steps that the remaining forwarding capacity of a repeater is considered according to the size of a reserved light path frequency spectrum, when the remaining capacity of the repeater is enough, the number of frequency slots needing to be reserved is different under the condition of different service transmission, an available frequency spectrum block meeting a service request is dynamically selected, the size of the reserved frequency spectrum block is compared with the maximum service request rate, the maximum reserved frequency spectrum block which does not exceed the maximum service request rate is selected, and the waste of bandwidth resources reserved excessively by the frequency spectrum is reduced;
the light path cost formula is as follows:
Figure FDA0002498869190000041
Figure FDA0002498869190000042
Figure FDA0002498869190000043
wherein pi _ hop is hop number of the candidate optical path, pi _ cs is frequency spectrum continuity of the candidate optical path, β is a very small value, β is 0.0001, avoiding denominator is 0, cpFor the candidate lightpath traffic carrying capabilities,
Figure FDA0002498869190000044
the service condition of the ith frequency slot on the optical path candidate optical path p is set as 1 if the ith frequency slot is idle, otherwise, the service condition is set as 0;
Figure FDA0002498869190000045
representing the number of frequency slots contained in the maximum free spectrum block on the candidate lightpath p; b isnIs a set of idle spectrum blocks, R is a set of traffic bandwidth demand types,
Figure FDA0002498869190000046
the jth idle spectrum block bandwidth size R of the candidate lightpath pkThe required bandwidth size for the kth type of traffic in the set R.
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Publication number Priority date Publication date Assignee Title
CN108881046A (en) * 2018-07-12 2018-11-23 清华大学深圳研究生院 A kind of service chaining dynamic dispatching method and device
CN109547876A (en) * 2018-12-29 2019-03-29 重庆邮电大学 A kind of adaptive guard rank method under elastic optical network twin failure
CN109862447B (en) * 2019-02-22 2021-10-15 郑州轻工业学院 Elastic optical network spectrum allocation method for minimizing total reduction of network idle resources
CN109936782B (en) * 2019-04-23 2021-08-17 河北工程大学 Elastic optical network spectrum allocation method based on multi-hop routing
CN111654442B (en) * 2020-04-20 2021-03-19 北京邮电大学 Dynamic service grooming processing method and device in elastic optical network
CN114039920B (en) * 2021-10-19 2022-07-12 苏州大学 Load balancing flow grooming method and system based on IP over Quasi-CWDM network
CN115329987B (en) * 2022-08-04 2023-07-21 苏州大学 User selection method in federal learning system

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2015052468A1 (en) * 2013-10-11 2015-04-16 British Telecommunications Public Limited Company Optical data transmission method and apparatus
CN104836736A (en) * 2015-05-26 2015-08-12 重庆邮电大学 Spectrum sensing-based energy efficiency resource allocation and path reconfiguration method in elastic optical network
CN106712839A (en) * 2017-01-03 2017-05-24 重庆邮电大学 Path protection method based on spectrum availability and protection bandwidth sharing sensing in elastic optical network
CN107204935A (en) * 2017-07-12 2017-09-26 苏州大学 The probability of malfunction and load balancing mean method and system of the flexible optical-fiber network of frequency spectrum
CN107426110A (en) * 2017-09-22 2017-12-01 苏州大学 Adaptive load balancing energy consumption optimization method and system in the flexible optical-fiber network of frequency spectrum

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2015052468A1 (en) * 2013-10-11 2015-04-16 British Telecommunications Public Limited Company Optical data transmission method and apparatus
CN104836736A (en) * 2015-05-26 2015-08-12 重庆邮电大学 Spectrum sensing-based energy efficiency resource allocation and path reconfiguration method in elastic optical network
CN106712839A (en) * 2017-01-03 2017-05-24 重庆邮电大学 Path protection method based on spectrum availability and protection bandwidth sharing sensing in elastic optical network
CN107204935A (en) * 2017-07-12 2017-09-26 苏州大学 The probability of malfunction and load balancing mean method and system of the flexible optical-fiber network of frequency spectrum
CN107426110A (en) * 2017-09-22 2017-12-01 苏州大学 Adaptive load balancing energy consumption optimization method and system in the flexible optical-fiber network of frequency spectrum

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
"Joint IT and spectrum resource load balancing for VNF selection in inter-datacenter elastic optical networks";BoLi等;《IEEE》;20171001;全文 *
"弹性光网络中负载均衡的优先共享通路保护";熊余等;《上海交通大学学报》;20170531;第51卷(第5期);全文 *

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