CN102143545A - Router and packet forwarding method thereof - Google Patents

Abstract

The invention discloses a router and a packet forwarding method thereof. The router comprises a node density calculating module, a transmission radius calculating module, an adjacent node detecting module, a forwarding node detecting module and a forwarding node selecting module, wherein the node density calculating module is used for calculating and storing network node density in a storage network; the transmission radius calculating module is used for calculating the maximum transmission radius of one node and storing the maximum transmission radius to the node; and the adjacent node detecting module is used for detecting the adjacent nodes in the maximum transmission radius of the node and storing the transmission distance from the adjacent nodes to the node. In the router and the packet forwarding method thereof, the forwarding node range is determined by adopting the optimum transmission radius and the maximum transmission radius, and the interruption and abnormality of communication caused by communication empty is effectively avoided by a surface traversal technology. Furthermore, in the invention, the utilization ratio of node energy is improved, so that the service lives of the node and the network are prolonged.

Description

Router and packet-forwarding method thereof

Technical field

The present invention relates to a kind of router and packet-forwarding method thereof, particularly relate to a kind of router and packet-forwarding method thereof that is used for wireless sensing network.

Background technology

The transducer of numerous types that wireless sensor network had, diversified phenomenon in the detectable surrounding enviroment such as size, speed and direction that comprise earthquake, electromagnetism, temperature, humidity, noise, luminous intensity, pressure, soil constituent, mobile object.Micro sensing technology and Wireless Networking technology based on MEMS (MEMS (micro electro mechanical system)) are that wireless sensor network has been given wide application prospect.These potential applications can reduce: field such as military affairs, aviation, anti-terrorism, explosion-proof, the disaster relief, environment, medical treatment, health care, household, industry, commerce.

In the communication process of existing wireless sensor network, greedy pass-through mode is based on very important a kind of pass-through mode in the data forwarding of the route in geographical position in the wireless sensor network, but this pass-through mode suffers from route cavity problem easily, thereby cause communication interruption and unusual, the geographical position that utilizes sensing node of this external wireless sensor network is come in the process of packet forward data, because the selection strategy of the next-hop node of greedy pass-through mode is too simple, though though the nearest node of chosen distance destination node can reduce jumping figure, reduce time delay, but this pass-through mode has also increased the energy consumption of node, has reduced node and network life.

Summary of the invention

The technical problem to be solved in the present invention is in order to overcome the big defective of energy consumption of the node that selection strategy that greedy pass-through mode of the prior art meets with communication cavity and next-hop node easily too simply causes, a kind of router and packet-forwarding method thereof are provided, thereby when effectively evading the communication cavity, improve energy utilization ratio.

The present invention solves above-mentioned technical problem by following technical proposals:

A kind of router, its characteristics are that described router comprises:

One node density computing module is used for calculating the also network node density of storage networking;

One transmission radius calculation module is used to calculate the maximum transmitted radius of a node and is stored to described node, and calculates the optimal transmission radius of described node and be stored to described node according to described network node density;

One neighbors detection module is used to detect the neighbors in the maximum transmitted radius of described node and stores the transmission range of described neighbors to described node;

One forward node detection module is used to detect the neighbors that whether has the transmission range minimum in the optimal transmission radius of described node;

One forward node is selected module, is used for the testing result according to described forward node detection module, and the neighbors of transmission range minimum is as forward node in the neighbors of the interior transmission range minimum of selection optimal transmission radius or the selection maximum transmitted radius.

Preferably, described forward node selects module also to cause the empty neighbors of communicating by letter by the eliminating of face traversal technology.

Preferably, described traversal technology is GPSR, CLDP or Bypass face traversal technology.

A kind of packet-forwarding method of described router may further comprise the steps:

S ₁₀₁, the node density computing module calculate to obtain the network node density in the network, the maximum transmitted radius of transmission radius calculation module computing node also is stored to described node;

S ₁₀₂, transmission radius calculation module is according to the optimal transmission radius of described network node density computing node and be stored to described node;

S ₁₀₃, the neighbors detection module detects the neighbors in the maximum transmitted radius of described node and stores the transmission range of described neighbors to described node;

S ₁₀₄, forward node detection module detection node the optimal transmission radius in whether have the neighbors of transmission range minimum, if testing result is for being then to enter step S ₁₀₅, otherwise enter step S ₁₀₆

S ₁₀₅, to select module to select the neighbors of transmission range minimum in the optimal transmission radius be forward node to forward node;

S ₁₀₆, forward node select module select transmission range minimum in the maximum transmitted radius neighbors as forward node.

Preferably, it is GPSR, CLDP or Bypass face traversal technology as forward node and described traversal technology that described forward node selects module also to select neighbors by the face traversal technology, and at step S ₁₀₅In may further comprise the steps:

Forward node selection module detects by described GPSR, CLDP or Bypass face traversal technology and gets rid of in the optimal transmission radius and causes the empty neighbors of communicating by letter.

Preferably, it is GPSR, CLDP or Bypass face traversal technology as forward node and described traversal technology that described forward node selects module also to select neighbors by the face traversal technology, and at step S ₁₀₆In may further comprise the steps:

Forward node selection module detects by described GPSR, CLDP or Bypass face traversal technology and gets rid of in the maximum transmitted radius and causes the empty neighbors of communicating by letter.

Positive progressive effect of the present invention is:

Router of the present invention and packet-forwarding method thereof, determine the forward node scope by adopting optimal transmission radius and maximum transmitted radius, and effectively evaded the empty communication disruption that causes of communication and unusual by the face traversal technology, the present invention has also further improved the utilance of node energy in addition, thereby has increased node and network life.

Description of drawings

Fig. 1 is the circuit structure block diagram of the preferred embodiment of router of the present invention.

Fig. 2 is the schematic diagram of network node in the optimal transmission radius calculation of the present invention.

Fig. 3 is transmission radius of the present invention and energy efficiency figure.

Fig. 4 is the flow chart of the preferred embodiment of packet-forwarding method of the present invention.

Embodiment

Provide preferred embodiment of the present invention below in conjunction with accompanying drawing, to describe technical scheme of the present invention in detail.

Figure 1 shows that the circuit structure block diagram of router of the present invention, comprising a node density computing module 1, a transmission radius calculation module 2, a neighbors detection module 3, a forward node detection module 4 and a forward node select module 5,

Wherein said node density computing module 1 is used for calculating the also network node density of storage networking.The method of known network node density is not just being given unnecessary details herein in the wireless network of the method employing prior art of wherein said computing network node density.

Described transmission radius calculation module 2 is used for the maximum transmitted radius of computing network node and is stored to described node, and calculates the optimal transmission radius of described node and be stored to described node according to described network node density.Known in the wireless network that wherein said maximum transmitted radius calculation is a prior art, just do not giving unnecessary details herein.Being calculated as follows of described in addition optimal transmission radius is described:

Network node as described in Figure 2, at first the mathematical expectation transmitted to destination node by neighbors of node is as shown in the formula shown in (1):

$E\left(P\right)=\frac{3x^{2}r-r^3-6{\∫}_0^r{\∫}_r^x{\mathrm{ve}}^{-\mathrm{\ρ}{A}_1(v-p,v,r)}\mathrm{dvdp}}{3(x^2-2{\∫}_r^x{\mathrm{ve}}^{-\mathrm{\ρ}{A}_{\mathrm{SD}}(v,r)}\mathrm{dv})}---\left(1\right)$

Wherein x is the maximum radius of network's coverage area, so x is a fixed value, and for example 200 meters etc.R is signal transmission radius, i.e. the node maximum transmitted radius of node.V is the distance of source node S to destination node D as shown in Figure 2.Z is the distance of the neighbors T of source node S selection apart from destination node D.ρ is the node coverage density in the network.As shown in Figure 2, A _SDThe overlapping region of the maximum transmitted scope that constitutes for the maximum transmitted radius of source node S and destination node D, A ₁For the transmission range of source node S maximum transmitted radius formation and with destination node D is that center of circle z is the overlapping region of the circle of radius, A ₂Be regional A _SDIn deduct regional A ₁After remaining area.

Can obtain following formula (2) and (3) by calculating:

$A_{\mathrm{SD}}(v,r)={\mathrm{<figure-callout\; id="2"\; label="r"\; filenames="HDA0000048743080000011.png"\; state="\{\{state\}\}">r</figure-callout>}}^2{\cos }^{-1}\left(\frac{r}{2v}\right)+v^2{\cos }^{-1}(1-\frac{{\mathrm{<figure-callout\; id="2"\; label="r"\; filenames="HDA0000048743080000011.png"\; state="\{\{state\}\}">r</figure-callout>}}^2}{2v^2})-\frac{1}{2}r\sqrt{(2v+r)(2v-r)}---\left(2\right)$

$A_1(z,v,r)={\mathrm{<figure-callout\; id="2"\; label="r"\; filenames="HDA0000048743080000011.png"\; state="\{\{state\}\}">r</figure-callout>}}^2{\cos }^{-1}\left(\frac{{\mathrm{<figure-callout\; id="2"\; label="r"\; filenames="HDA0000048743080000011.png"\; state="\{\{state\}\}">r</figure-callout>}}^2+v^2-{\mathrm{<figure-callout\; id="2"\; label="z"\; filenames="HDA0000048743080000011.png"\; state="\{\{state\}\}">z</figure-callout>}}^2}{2\mathrm{rv}}\right)z^2{\cos }^{-1}\left(\frac{z^2+v^2-v^2}{2\mathrm{vz}}\right)-\frac{1}{2}\sqrt{(r+v+z)(v+z-r)(r+v-z)(r+z-v)}---\left(3\right)$

Aggregative formula (1), (2) and (3) can obtain the formula (4) of following transmission radius and energy efficiency:

$e\left(r\right)\frac{3x^{2}r-r^3-6{\&Integral;}_0^r{\&Integral;}_r^x{\mathrm{ve}}^{-\mathrm{\&rho;}{A}_1(v-p,v,r)}\mathrm{dvdp}}{3(k_1{r}^{\mathrm{\&omega;}}+{\mathrm{<figure-callout\; id="2"\; label="k"\; filenames="HDA0000048743080000011.png"\; state="\{\{state\}\}">k</figure-callout>}}_2+E_r)(x^2-2{\&Integral;}_r^x{\mathrm{ve}}^{-\mathrm{\&rho;}{A}_{\mathrm{SD}}(v,r)}\mathrm{dv})}---\left(4\right)$

Can obtain as shown in Figure 3 transmission radius and energy efficiency figure by aforesaid formula, and can determine that by described formula the optimal transmission radius of node is less, also can find the corresponding different optimal transmission radius of network of different densities in addition by Fig. 3, and the network that node density is high, the optimal transmission radius of node is less.

The transmission range that described neighbors detection module 3 is used to detect the neighbors in the maximum transmitted radius of described node and stores described neighbors is to described node; Described forward node detection module 4 is used to detect the neighbors that whether has the transmission range minimum in the optimal transmission radius of described node; Described forward node selection module 5 is used for the testing result according to described forward node detection module 4, selects the neighbors of transmission range minimum in the optimal transmission radius or the neighbors of the interior transmission range minimum of selection maximum transmitted radius.

In addition, forward node selection module 5 is also got rid of by the face traversal technology and is caused the empty neighbors of communicating by letter, thereby the problem that can effectively evade the communication cavity by the face traversal technology, what the traversal technology of face described in the present embodiment adopted is GPSR (greedy peripheral stateless route), CLDP (crosslinked detection protocol) or Bypass face traversal technology, can adopt the face traversal technology of other kinds or form in addition according to the actual needs of radio sensing network.Transmit radius and adopt above-mentioned traversal technology by enlarging in the present embodiment, thereby when in the optimal transmission radius, not having node or meeting with the communication cavity, can effectively change the selection of neighbors, thus the problem of having evaded the communication cavity and not had node.

The operation principle of the router of present embodiment is as described below:

At first node density computing module 1 calculates the network node density that obtains in the network, and the maximum transmitted radius of described transmission radius calculation module 2 computing nodes also calculates the optimal transmission radius by described network node density.

Neighbors that the maximum transmitted radius that described then neighbors detection module 3 detected and write down described node is interior and neighbors are to the transmission range of node.

After this forward node detection module 4 detects the neighbors that whether has the transmission range minimum in the optimal transmission radius of node.If testing result is for being, then forward node selects module 5 to cause the empty neighbors of communicating by letter by the eliminating of face traversal technology, the neighbors of selecting the transmission range minimum then is a forward node, thereby the transmitted in packets that is used for data, otherwise, forward node selects module 5 to enlarge the scope of selecting forward node, promptly detect the node of transmission range minimum in the maximum transmitted radius, and by the definite neighbors of selecting to cause empty problem of getting rid of of face traversal technology, the neighbors of selecting the transmission range minimum then is a forward node.

Figure 4 shows that the flow chart of packet-forwarding method of the present invention, comprising following steps:

Step 101, the node density computing module calculates the network node density that obtains in the network, and the maximum transmitted radius of transmission radius calculation module computing node also is stored to described node.

Step 102, transmission radius calculation module is according to the optimal transmission radius of described network node density computing node and be stored to described node.

Step 103, neighbors detection module detect the neighbors in the maximum transmitted radius of described node and store the transmission range of described neighbors to described node.

Whether step 104 exists the neighbors of transmission range minimum in the optimal transmission radius of forward node detection module detection node, if testing result is for being then to enter step 105, otherwise enter step 106.

It is forward node that step 105, forward node select module to select to cause the neighbors of empty problem and select the neighbors of transmission range minimum by GPSR, CLDP or the eliminating of Bypass face traversal technology in the optimal transmission radius, and flow process finishes.

It is forward node that step 106, forward node select module to select to cause the neighbors of empty problem and select the neighbors of transmission range minimum by GPSR, CLDP or the eliminating of Bypass face traversal technology in the maximum transmitted radius, and flow process finishes.

Though more than described the specific embodiment of the present invention, it will be understood by those of skill in the art that these only illustrate, protection scope of the present invention is limited by appended claims.Those skilled in the art can make numerous variations or modification to these execution modes under the prerequisite that does not deviate from principle of the present invention and essence, but these changes and modification all fall into protection scope of the present invention.

Claims (6)

1. a router is characterized in that, described router comprises:

One node density computing module is used for calculating the also network node density of storage networking;

One transmission radius calculation module is used to calculate the maximum transmitted radius of a node and is stored to described node, and calculates the optimal transmission radius of described node and be stored to described node according to described network node density;

One neighbors detection module is used to detect the neighbors in the maximum transmitted radius of described node and stores the transmission range of described neighbors to described node;

One forward node detection module is used to detect the neighbors that whether has the transmission range minimum in the optimal transmission radius of described node;

One forward node is selected module, is used for the testing result according to described forward node detection module, and the neighbors of transmission range minimum is as forward node in the neighbors of the interior transmission range minimum of selection optimal transmission radius or the selection maximum transmitted radius.

2. router as claimed in claim 1 is characterized in that, described forward node selects module also to cause the empty neighbors of communicating by letter by the eliminating of face traversal technology.

3. router as claimed in claim 2 is characterized in that, described traversal technology is GPSR, CLDP or Bypass face traversal technology.

4. the packet-forwarding method of a router as claimed in claim 1 is characterized in that may further comprise the steps:

S ₁₀₁, the node density computing module calculate to obtain the network node density in the network, the maximum transmitted radius of transmission radius calculation module computing node also is stored to described node;

S ₁₀₂, transmission radius calculation module is according to the optimal transmission radius of described network node density computing node and be stored to described node;

S ₁₀₃, the neighbors detection module detects the neighbors in the maximum transmitted radius of described node and stores the transmission range of described neighbors to described node;

S ₁₀₄, forward node detection module detection node the optimal transmission radius in whether have the neighbors of transmission range minimum, if testing result is for being then to enter step S ₁₀₅, otherwise enter step S ₁₀₆

S ₁₀₅, to select module to select the neighbors of transmission range minimum in the optimal transmission radius be forward node to forward node;

S ₁₀₆, forward node select module select transmission range minimum in the maximum transmitted radius neighbors as forward node.

5. packet-forwarding method as claimed in claim 4 is characterized in that, it is GPSR, CLDP or Bypass face traversal technology as forward node and described traversal technology that described forward node selects module also to select neighbors by the face traversal technology, and at step S ₁₀₅In may further comprise the steps:

Forward node selection module detects by described GPSR, CLDP or Bypass face traversal technology and gets rid of in the optimal transmission radius and causes the empty neighbors of communicating by letter.

6. packet-forwarding method as claimed in claim 4 is characterized in that, it is GPSR, CLDP or Bypass face traversal technology as forward node and described traversal technology that described forward node selects module also to select neighbors by the face traversal technology, and at step S ₁₀₆In may further comprise the steps:

Forward node selection module detects by described GPSR, CLDP or Bypass face traversal technology and gets rid of in the maximum transmitted radius and causes the empty neighbors of communicating by letter.

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