CN102164082B - MANEMO mobile network system for optimizing nested network routings and optimization method thereof - Google Patents

Abstract

The invention discloses a MANEMO mobile network system with a nested network routing optimization function and an optimization method thereof. A multi-hop routing protocol processing module, a network mobility protocol processing module and a mobile node agent module are added in an MR (Mobile Router) in a system and the MR is in charge of the real-time access of a nested mobile network and a VMN (Virtual Mobile Node) in the whole mobile network. The newly-added VMN-HA (Home Agent) is provided with an MIPv6 (mobile internet protocol version 6) protocol processing module, an access node user management module and a filter module; communication routings between the nested mobile network and VMN and a backbone network is optimized by the MANEMO mobile network system according to the current NEMO BS (network mobile basic support) protocol; the MR directly connected with an AR (Access Router) is selected as a root router; and the root router replaces the roaming mobile network and VMN to execute the binding and register with the HA of the roaming mobile network and VMN, and replaces the VMN to communicate with a CN (Correspondent Node) end. A multi-hop routing protocol is realized in a multi-hop domain so as to realize direct communication among different network nodes in the same multi-hop domain, thereby preventing the problem of multiple triangle routings caused by the nested network and improving the communication efficiency of the mobile network.

Description

Optimize MANEMO mobile network system and the optimization method thereof of nested networks route

Technical field

The present invention relates to a kind of MANEMO mobile network system of nested networks route and method of routing optimality thereof optimized, exactly, the present invention is based on current mobile substantially Routing Protocol, nested mobile network is optimized with the route of communicating by letter of backbone network with the visit mobile node, selection and the direct-connected mobile network's router of couple in router are as root router, and the mobile network of replacement roaming and mobile node and its home agent are bound; The inner multi-hop Routing Protocol that adopts in the multi-hop territory has been realized the direct communication between different mobile network nodes in the same multi-hop territory, thereby has been reached the many triangles routing issue that prevents that nested networks from causing again, improves mobile network communication efficient.The route-optimization technique field that belongs to the mobile network.

Background technology

At present, mobile network's development is comparative maturity, the main agreement of the mobile management of carrying out is MIPv6(Mobile Internet Protocol Version6, be RFC3775) and network move basic support NEMO BS agreement (Network Mobility Basic Support Protocol, i.e. RFC3963).MIPv6 is mainly used in the mobile management of single computer and supports the main frame mobility, defined mobile node keeps continuity in moving process method, and still, it does not provide the support of network mobility.NEMO BS agreement is the expansion to MIPv6, has defined the mobile network and has made the as a whole method that keeps conversation continuity in moving process.

Stipulate according to agreement, backbone network distributes several mobile network's prefixes MNP(Mobile Network Prefix to the mobile network), mobile network node MNN(Mobile Network Node) obtain a home address HoA(Home Address according to MNP).When the mobile network moves to foreign link, mobile network's router MR(Mobile Router) obtains Care-of Address CoA(Care of Address).The mapping table of the CoA of MR and MNP are safeguarded by mobile network's home agent HA (Home Agent), after MR obtains CoA, to register to home agent, to set up the bidirectional tunnel between itself and the HA, continue to use its home address HoA for mobile network node MNN.When communication node CN(Correspondent Node) sending packet to mobile network node, grouping at first sends to mobile network's home agent HA.After HA receives the packet that sends to the mobile network, by the duplex channel between MR and the HA, grouping is sent on the current Care-of Address of MR.After MR receives grouping, after the decapsulation processing, it is transmitted to the corresponding mobile network node of mobile network.

Referring to Fig. 1, when introducing existing network and having multilayer nest, how to use network mobility to support " many triangles route " problem that the NEMO agreement exists substantially.Among the figure, MR2-MR5 enters the Internet by MR1 respectively, and MR2 wherein is nested under the MR1, and MR3 and MR4 are nested under the MR2, and MR5 is nested under the MR4, forms a nested configuration layer by layer.MNN communication process under communication node CN and the MR5 is as follows: CN sends to packet in the network, intercepted and captured by the home agent HA 5 of MR5 according to destination address information, according to the binding record of MR5 and HA5, packet transmits with the route of HA5 → HA4 → HA2 → HA1 → MR1 → MR2 → MR4 → MR5 → MNN.In the transport process, packet encapsulates respectively at HA5, HA4, HA2 and HA1, also carries out decapsulation respectively at MR1, MR2, MR4 and MR5.

At present, the prior art that solves NEMO nested networks routing optimality problem mainly contains two kinds of thinkings: a kind of is by source routing mechanism, " many triangles route " problem of solution nested mobile network; Another kind is by with a couple in router AR(Access Router) under all MR constitute a tree-shaped hierarchical topology structure, only set up bidirectional tunnel between the home agent by top layer MR and bottom MR and communicate by letter with outer net.

For example, in February, 2007, " the IPv6 Reverse Routing Header and its application to Mobile Networks " that P.Thubert and M.Molteni deliver, a kind of reverse routing header RRH(Return Routing Header is proposed) agreement, adopt the scheme of source routing mechanism optimization nested mobile network exactly.It is to adopt a kind of new routing iinformation of " reverse routing header " record from MNN to CN, and MR sets up bidirectional tunnel by the root router that directly links to each other with AR and the HA of oneself, has omitted the HA of middle MR.

When packet sent to CN from MNN, first MR distributed the RRH of necessary amount on the path, and MR is exactly the number of the RRH that need distribute in the tunnel head to the step number of AR on the path.In first RRH with the HA of the direct-connected MR of MNN as destination address, the CoA of this MR is as source address, the MR in the path inserts the CoA of oneself respectively in the next RRH as source address, and destination address does not change.Packet sends to the HA of the MR that directly links to each other with MNN by bidirectional tunnel, in the time of HA deblocking packet, and clauses and subclauses and data are mail to CN among the buffer memory RRH.After HA set up buffer memory, the data that CN mails to MNN just can use the direction opposite with RRH to send.

Above-mentioned RRH agreement solves the nested mobile network route-optimization technique and has following defective: the RRH method is used reverse routing header record routing iinformation, fundamentally do not solve the problem of data multilayer encapsulation, when level of nesting chin-deep, then reverse routing header information will increase very loaded down with trivial detailsly, causes the decline of communication efficiency.

(application number: 200810104453.3) propose a kind of routing optimization method of the solution nested mobile network based on the tree topology structure: all MR under couple in router AR form a tree topology structure to Chinese patent application " a kind of implementation method of mobile network's route and network ", each MR is as a node, higher level MR need preserve the topology information that its all MR of subordinate safeguard, and bears routing iinformation and the transfer of data of all MR of lower floor.Root router is preserved whole with the topology of networks of couple in router AR as access point.The bidirectional tunnel of setting up between HA and the root router of all MR by oneself is communicated by letter with outer net, and higher level MR does not encapsulate the data of subordinate, only forwards the data to the higher level MR of oneself, arrives root router up to data, is sent to CN by bidirectional tunnel.

There is following defective in this patent application: at first, computing and storage burden diversity ratio based on the MR at different levels of the routing optimization manner of tree topology structure are bigger, higher level MR will manage topology information and the data of its all MR of subordinate and transmit, especially the MR quantity under AR more for a long time, this difference shows more outstandingly.Moreover each MNN or MR have only a route with communicating by letter of outer net.Mobile network's mobility makes topology of networks be in the state that constantly changes, and when higher level MR moves to following time of other AR, all MR of this MR subordinate will rebuild route, and this situation is unfavorable for keeping communication continuity.

Therefore, how nested mobile network and visit mobile node and the problem that the route of communicating by letter of backbone network is optimized are just become focus and the focus of scientific and technical personnel's concern in the industry.

Summary of the invention

In view of this, the purpose of this invention is to provide a kind of routing optimization method of optimizing the MANEMO mobile network system of nested networks route, the present invention is based on the basic supported protocol of current network mobility, to nested mobile network and communicate by letter route implementing optimize of visit mobile node with backbone network, mobile network's router that selection and couple in router directly link to each other is as root router, replaces the mobile network of roaming and mobile node and its home agent to bind; By the inner multi-hop Routing Protocol of realizing in the multi-hop territory, realize the direct communication between different mobile network nodes in the same multi-hop territory, thereby reach the many triangles routing issue that prevents that nested networks from causing again, improved mobile network communication efficient.

In order to reach the foregoing invention purpose, the invention provides a kind of routing optimization method with MANEMO mobile network system of nested mobile network routing optimality function, it is characterized in that described method comprises following operating procedure:

(1) each MR receives the identity information of couple in router periodic broadcast respectively, receives that the MR of same couple in router broadcast packet forms a MANET MANET that adopts the OLSR protocol communication each other, with the Care-of Address of MR as source address or destination address; Wherein, the MR that directly connects couple in router becomes root router, and the Ground Router flag scaling option in its Hello message is set to 1 automatically, and other MR of broadcast announcement;

When (2) Wai Di MR roams into new couple in router scope, set up Binding Update by the root router of its selection to home agent; This step further comprises following content of operation:

(21) the MR information of access route of finding its reception and own couple in router MR_Hello message perceive it and are in roaming state not simultaneously, just put out root router in order from all MR_Hello message of oneself reception and tabulate; This root router tabulation is provided with following three clauses and subclauses: be used for the Ground_MR field that record can receive the root router Care-of Address of its Hello message, be used for to select root router, the storage root router is to the distance of this MR or the hop_count field of jumping figure, is used for this root router clauses and subclauses of mark Life_time (s) field of effective time;

(22) roaming MR from root router tabulation, select the jumping figure minimum effective root router as destination address, the Binding Update request of itself and home agent is sent to root router by the OLSR agreement; Root router receives this Binding Update request, judge this News Category and continue and send: if this root router is different with the home agent of source MR, then this root router encapsulates this packet, be sent to the home agent of this root router by the bidirectional tunnel between MR and the home agent, be sent to the home agent of source MR again by the bidirectional tunnel between the home agent; If root router is identical with the home agent of source MR, then packet directly is sent to the purpose home agent by this root router;

When (3) each visit mobile node roams into new MANEMO subnet, all register reverse route by root router, substitute visit mobile node and its home agent foundation binding by root router, set up binding with Correspondent Node again, thereby realize routing optimality.This step further comprises following content of operation:

(31) the visit mobile node receives the broadcasting of new MR, perceives and lays oneself open to roaming state, just sends the registration request that comprises own home address to this new MR; This new MR receives the registration request of visit mobile node, behind the Care-of Address of interpolation therein oneself, sends reverse route registration request to the own nearest root router of distance; Root router is stored reverse routing table after receiving reverse route registration request;

(32) root router substitutes the visit mobile node and makes up Binding Update request with its home agent: source address is the root router Care-of Address, and destination address is the home agent of the access node nearest apart from root router;

(33) after the home agent of access node receives the Binding Update request, will visit mobile node information and be stored in the tabulation of visit node user, and make up the Binding Update acknowledge message that mails to the visit mobile node; Simultaneously, all destination addresses mail to the corresponding root router of this visit mobile node again for the packet of the visit mobile node of existence in its visit node user tabulation in the interception network;

(34) after root router received the Binding Update acknowledge message that the home agent of access node sends, the binding relationship of visit mobile node by the home agent of root router and access node just foundation finished;

(35) destination address that Correspondent Node sends in the network is for after the packet of visit mobile node intercepted and captured by the home agent of this access node, the home agent of this access node is according to the information in the tabulation of visit node user, send this packet the home agent of root router to, transfer to root router again;

(36) root router receives destination address that the home agent of access node sends and is the packet of visit mobile node, and the reverse route according to should the visit mobile node in the reverse routing table sends packet to the visit mobile node; Simultaneously, root router substitutes the bind-request message of visit mobile node structure and Correspondent Node, sends to Correspondent Node; After Correspondent Node receives this bind request, the home address of visiting mobile node is stored in list of bindings, sends binding acknowledgement message to root router again; So far, mobile network node and Correspondent Node are finished binding and are set up, and root router just sends this access node for the home agent of access node by its home agent and Correspondent Node is finished the message that binding is set up; After this, Correspondent Node just can pass through the root router direct communication with the visit mobile node, and the home agent that need not access node is carried out forwarding capability;

(37) home agent of access node receives access node and the correspondent node that the home agent of root router sends and finishes the message that binding is set up, Correspondent Node address in the message is stored in the Correspondent Node address field of this access node in the access node user list, and the mapping that generates this Correspondent Node address and this access node address is right, add in the mapping table of filter module, no longer tackle the packet that this Correspondent Node is issued this access node later on.

The key problem in technology point of the present invention's innovation is: the MR of system of the present invention sets up the multi-hop Routing Proccess Unit of being responsible in the multi-hop intra-area communication, the network mobility protocol process module with root router function and mobile node proxy module, is in charge of nested mobile network and the real-time access of visiting mobile node among the whole mobile network.Also on the basic supported protocol of network mobility basis, the home agent HA of newly-increased access node VMN, it is provided with mobile IPv 6 protocol processing module, access node user management module and filter module, be responsible for setting up binding with access node, and tackle the packet of not issuing access node with the Correspondent Node of the direct binding of access node, send access node to by root router; It uses multi-hop Routing Protocol, can realize communicating by letter of whole mobile network and root router, thereby improve mobile network's access scope.The basic supported protocol of current network mobility is based in system of the present invention, the optimization of having communicated by letter route implementing to nested mobile network and visit mobile node and backbone network, by select and MR that couple in router directly links to each other as root router, root router replaces the mobile network of roaming and visit mobile node and its home agent to register, and replaces visit mobile node and Correspondent Node to communicate.Realize the multi-hop Routing Protocol by inner in the multi-hop territory, thereby realized the direct communication between different mobile network nodes in the same multi-hop territory, thereby reach the many triangles routing issue that prevents that nested networks from causing, improved mobile network communication efficient.

The technology of the present invention has following advantage:

(1) all mobile networks under the identical network access point AR being delimited is a MANET network domains, between these mobile networks, use OLSR multi-hop Routing Protocol, thus, many triangles routing issue has been avoided in communication fully between the mobile network in each MANET network domains.

(2) root router is to roaming mobile network's role: when nonlocal mobile network roams to this MANET network domains, after its MR obtains Care-of Address CoA, the Binding Update request that will be sent to its HA by the OLSR Routing Protocol sends to the present root router place of this MANET, sends to the purpose home agent HA by root router.

(3) root router is visited mobile node VMN role to the visit mobile node: when outer accessing mobile node roams to this mobile network, mobile network node is by new MR, root router to this MANET network domains sends reverse route foundation request, simultaneously, root router replaces VMN to set up binding relationship to Correspondent Node.

(4) the address configuration mode of MR: the address of MR comprises AR_ID and mobile network's prefix MNP two parts information, identifies mutually by MNP between the MR of same MANET network domains, distinguishes mutually by AR_ID between the MR of different MANET network domains.When MR roamed between different MANET network domains, only the hello that broadcasts according to other MR guaranteed the repair free of charge the AR_ID that changes its address and partly constructs its Care-of Address CoA, and need not revise its unique MNP.

(5) the hello bag of revising MR_Hello bag content: MR is substantially according to the Hello packet format in the OLSR agreement, and the present invention has added the root router option on this basis; Specific practice is: MR periodically detects the broadcast message of AR, if find that own jumping figure with AR is 1, namely directly link to each other with AR, and the root router option is set to 1, otherwise is 0; Simultaneously, this option is that 0 MR need preserve the effectively tabulation of root router in the local MANET network domains.

(6) simplify the terminal node function: the most of route related work among the present invention all has been transferred to MR and HA, for example root router replaces the visit mobile node of roaming to set up Binding Update to its home agent, and replace visit mobile node and Correspondent Node to bind etc., thereby computation complexity and the energy consumption of the terminal equipment that reduces to know clearly, to existing mobile terminal device require low, strengthened mobile network's practicality, and be easy to realize.

In a word, the present invention can either avoid that reverse routing header increases with the nested number of plies in the RRH scheme, overcome in the tree topology structure MR computings at different levels again and storage burden difference is big, and a large amount of route reconstruct that when higher level MR moves, produce, the various defectives of threat continuity.The present invention adopts and use the communication of OLSR Routing Protocol between the NEMO network of sharing identical access point AR, and making between each subnet of close NEMO can direct communication and need not to transmit through separately HA; In the time of in nonlocal NEMO roams to new network insertion point range, the selected MR that directly links to each other with AR of its MR sends binding update messages by this root router to its home agent as root router; When single MNN roams to new NEMO subnet, send reverse route to root router and set up request, by root router and CN BOUND communication, thereby avoided many triangles routing issue that nested networks causes in the NEMO BS agreement, optimize the binding of roaming MR and its HA, and the binding of roaming MNN and CN, the communication efficiency of raising overall network.

Description of drawings

Fig. 1 is that the structure of nested mobile network is formed schematic diagram.

Fig. 2 is that the structure that the present invention optimizes the HA of MR in the MANEMO mobile network system of nested networks route and VMN is formed schematic diagram, and local stationary nodes LFN(Locak Fixed Node) the routing optimality schematic diagram of communicating by letter with Correspondent Node CN.

Fig. 3 is the schematic diagram that the present invention visits MR and the binding of its home agent HA.

Fig. 4 is the schematic diagram that the present invention visits MR and its HA binding under special circumstances.

Fig. 5 is that the present invention visits the packets of information reciprocal process sequential chart that mobile node VMN communicates by letter with CN.

Fig. 6 is the reverse routing table schematic diagram that root router of the present invention is safeguarded.

Fig. 7 is the root router tabulation schematic diagram of common MR among the present invention.

Fig. 8 is the visit mobile node VMN user list schematic diagram that VMN-HA safeguards among the present invention.

Fig. 9 is the data packet transmission time delay comparison diagram among the emulation embodiment of the present invention.

Figure 10 is the interior data packets for transmission quantity comparison diagram of setting-up time among the emulation embodiment of the present invention.

Figure 11 is VMN among the emulation embodiment of the present invention-HA binding time delay comparison diagram.

Embodiment

For making the purpose, technical solutions and advantages of the present invention clearer, the present invention is described in further detail below in conjunction with drawings and Examples.

For avoiding the many triangles routing issue in the nested mobile network, the present invention has introduced the OLSR route optimisation protocol of MANET network.In the network system environment of MANEMO, the networking mode between each mobile network (being MR) exists every characteristics of mobile ad hoc network MANET, uses the Routing Protocol of MANET most suitable between MR.But, for the basic supported protocol of MANET Routing Protocol and network mobility can be realized being combined preferably that the present invention has done a series of expansions and improvement for this reason.

Referring to Fig. 2, introduce that structure that the present invention has the MANEMO mobile network system of nested mobile network routing optimality function is formed and system in the local stationary nodes routing optimality of communicating by letter with Correspondent Node illustrate:

Be provided with portable terminal, mobile network's router MR(Mobile Router in the system of the present invention), the home agent HA (Home Agent) of MR and the home agent HA of access node VMN; MR(wherein such as the MR1 among the figure) directly connect the couple in router AR of backbone network, when namely transmission range has only one to jump between the two, this MR1 just is converted to the root router of being in charge of all MR in this multi-hop territory, adopt its root router function of Grounded Router flag scaling option broadcast announcement, and substitute the mobile network of roaming and the function that mobile node is carried out and its home agent is bound; This MR1 is provided with: the network mobility protocol process module (MR_NEMO) that is connected with multi-hop Routing Proccess Unit (MANET-OLSR) and mobile node proxy module (MR_Proxy_VMN) (as shown in Figure 2) respectively.The function of these modules is:

The multi-hop Routing Proccess Unit is responsible for the transfer of data in same multi-hop territory; When this MR becomes root router, after this module receives the periodic broadcast packet of AR, check that earlier this bag arrives the jumping figure that this MR experiences, judge the distance of himself and AR, and then the numerical value of Grounded Router flag scaling option is set; If jumping figure is 1, represent that this MR directly connects AR, then this scaling option is set to identify 1 of root router, and initial 2 bit of the Reserved reserved field in the Hello grouping that is about in the OLSR agreement are as Grounded Router flag option; The default value of this scaling option is 0 of the non-root router of sign, and namely traditional MR safeguards a effectively root router tabulation at present this moment, is used for selecting root router.

The network mobility protocol process module, when mobile network's subnet that this MR manages roved between the heterogeneous networks access point, this module was responsible for carrying out the operations of the basic supported protocol regulation of network mobility; When this MR becomes root router, this module is responsible for receiving the Binding Update request that roaming MR sends by the OLSR Routing Protocol, and the Care-of Address that adds oneself again encapsulates, and sends to the HA of oneself, send to the HA of roaming MR again by the bidirectional tunnel between the HA, nested to avoid deep layer.

The mobile node proxy module is used for the routing optimality that mobile node VMN and Correspondent Node are visited in realization, to avoid many triangles route between the two; This module is only just enabled when this MR becomes root router: receive the reverse route registration request that VMN sends; In the reverse routing table that this module is safeguarded, the Care-of Address of the MR at the present place of record VMN and the home address of himself, and the request of alternative VMN structure Binding Update mail to the HA of nearest VMN; Receive destination address that the HA of VMN sends then for the packet of this VMN, send this VMN to according to reverse routing table; Simultaneously, replace the Binding Update request of this VMN structure and Correspondent Node, mail to Correspondent Node; After receiving the binding acknowledgement message that Correspondent Node sends, as the communication agent of this VMN and Correspondent Node, the HA by root router sends binding to the HA of this VMN and sets up the message of finishing, and makes the HA of this VMN no longer tackle the packet that Correspondent Node is issued VMN.

Information flow reciprocal process among the MR between each module is as follows: the AR address field in other MR broadcast packet that MR will receive compares with the respective field of oneself, if both differences, and the quantity of the MR that this field is different with oneself is more than or equal to 3, then judge oneself to enter roaming state, otherwise be non-roaming state;

If this MR is in roaming state, then apply for Care-of Address by the network mobility protocol process module to AR, simultaneously by the Grounded Router flag option in its MR broadcast that receives, set up the root router tabulation of oneself, therefrom select and own nearest root router, set up Binding Update by root router and the HA of oneself again;

When this MR is in non-roaming state, then by other MR interactive communication in multi-hop Routing Proccess Unit use OLSR agreement and the multi-hop territory, simultaneously, receive the broadcast packet of AR, check AR and the distance of himself: if jumping figure is 1, then be the root router state, just broadcast its root router identity to other MR; Then, receive the Binding Update request that roaming MR sends by the network mobility protocol process module, and pass through the HA of oneself, replace roaming MR and its HA to carry out Binding Update; And receive the reverse route registration request that access node is sent by the mobile node proxy module, substituting VMN registers and binds with Correspondent Node to its HA, and the HA of the notice of the HA by root router VMN: after finishing the binding of VMN and Correspondent Node, no longer tackle the packet that this Correspondent Node mails to this VMN; If jumping figure greater than 1, then is common MR, need to preserve the root router tabulation.

The home agent HA of MR (not showing among Fig. 2) is provided with the mobile network protocol processing module for the HA function that realizes the basic supported protocol of network mobility, finish following function: the implicit message of supporting Binding Update BU, management during the MR roaming, receive and handle Binding Update BU message, produce and send binding acknowledgement BA message and set up passage with the Care-of Address of MR.

The home agent HA of VMN is provided with mobile IPv 6 protocol processing module, access node user management module and filter module (as shown in Figure 2); Access node user management module wherein is different from traditional HA, is used for safeguarding the roaming of VMN user list and management VMN; This VMN user list stores home address, root router Care-of Address and the Correspondent Node address at all VMN of this HA registration; The HA of VMN receives root router when substituting the Binding Update request that VMN sends, and after recording this VMN information and making up the Binding Update acknowledge message, mails to this VMN; Simultaneously, all destination addresses are the packet of the VMN that exists in this VMN user list in the interception network, and mail to the root router of this VMN correspondence; When receiving VMN that the root router home agent sends and Correspondent Node binding when setting up the message of finishing, Correspondent Node address in this message is inserted the Correspondent Node address field of this VMN in the VMN tabulation, and the mapping that generates this Correspondent Node address and this VMN address is right, makes an addition to the mapping table of filter module again.Filter module stores the mapping table of Correspondent Node address and VMN address, the packet of VMN address and Correspondent Node matching addresses in responsible prevention source address and destination address and the mapping table.Mobile Ipv6 protocol process module is used for receiving root router and substitutes VMN to the Binding Update request of the HA transmission of VMN by its HA, this request is transferred to the access node user management module, so that after the HA address of VMN address, root router address and root router all was stored in the VMN user list of its maintenance, mobile Ipv6 protocol process module sent the Binding Update acknowledge message to the HA of root router; Simultaneously, begin to tackle the packet of issuing this VMN in the network: the reverse path of preserving according to this VMN then: via root router HA → root router → VMN, packet is sent to the destination.

When the HA of VMN receives VMN that the HA of root router sends and Correspondent Node when finishing the message that binding sets up, the access node user management module is stored in the Correspondent Node address in this message the Correspondent Node address field of this VMN in the VMN user list, the mapping of this Correspondent Node address of regeneration and this VMN address is right, and makes an addition to the mapping table of filter module; After, when the HA of VMN receives the packet that Correspondent Node is issued its VMN that acts on behalf of, be introduced into filter module, in the mapping table of this filter module, check address and purpose VMN address thereof that whether this Correspondent Node is arranged, if do not have, then receive this packet by mobile Ipv6 protocol process module, according to the reverse path transmission packet of this VMN; Otherwise, abandon this packet.

As everyone knows, the AM of the many access points as external network of Internet marginal existence.A plurality of MR under each AM among the present invention constitute a MANET local domain (as the MR1 among Fig. 2).The Care-of Address of each MR is to be calculated by certain algorithm of setting by its AR address and its mobile network's prefix.MR analyzes the Care-of Address in the Hello bag oneself receive, if the AM address that draws identical with oneself then is recorded to this MR in the topology table.

For example, in communication process, MR1 detect AR with own be 1 apart from jumping figure, then the root router option that increases newly in the Hello grouping is set to 1, other MR is set to 0.When certain local stationary nodes will send packet to the node under the non-MR1, bag is sent to MR1, MR1 judges the residing territory of destination node by the destination address of analyzing packet.If destination node is positioned at local MANET network domains, MR1 just is made as source address the address of oneself in the outer route head of packet, destination address is made as the MR address of destination node, after this, packet is sent to the purpose router according to the OLSR Routing Protocol, and then arrives destination node.If destination node is arranged in non-local MANET network domains (for example: in Internet or the MANET network domains under other AR), source MR just is made as the root router address with the destination address in the outer route head.For example: in Fig. 2, local stationary nodes LFN under the MR5 will communicate by letter with the Correspondent Node CN among the Internet, after packet arrives root router MR1 by the OLSR agreement, root router MR1 encapsulated data packet, be sent to the HA home agent HA 1 of root router by MR1-HA1 bidirectional tunnel, HA1 is routed to the home agent HA 5 of MR5 with packet by HA1-HA5 bidirectional tunnel, and then is sent to Correspondent Node according to purpose MR address.

Introduce each operating procedure of routing optimization method that the present invention has the MANEMO mobile network system of nested mobile network routing optimality function below:

Step 1, the AR in the network periodically sends the broadcast packet that comprises this AR self address, is used for MR and sets up the route that inserts Internet.Each MR receives the broadcast in the network respectively and detects the Hello grouping that receives, can direct communication (being that jumping figure is 1) if detect AR and oneself, then this MR becomes root router, automatically the root router Ground Router flag scaling option in the Hello message of its broadcasting is set to the non-root router of 1(and is set to 0), and other MR of broadcast announcement.Each MR that receives same AR broadcast packet sets up one and is positioned at the MANET subnet that adopts the OLSR protocol communication under the same AR, each other by judging mobile network's prefix, with the Care-of Address of MR as source address or destination address.

Step 2, during communication, each node broadcasts self message, MR judges the residing territory of destination node by the destination address of analyzing packet.If destination address is identical with mobile network's prefix of local MANET subnet address, the illustration purpose node is positioned at MANET subnet inside, after MR encapsulates message, source address is made as the address of oneself, after destination address being made as the MR address of destination node, this packet is sent to destination node according to the OLSR Routing Protocol.

If destination address is different with mobile network's prefix of local MANET subnet address, the illustration purpose node is positioned at MANET subnet outside, after packet arrived root router MR1 by the OLSR agreement, root router MR1 will communicate by letter with destination node by the basic supported protocol of network mobility as the agency of source node.

Referring to Fig. 3, when the MR that introduces the other places roams into new AR scope (accesses network), the process that set up Binding Update by root router and its home agent of its selection;

(1) MR5 receives the broadcast packe in the network, when MR5 moves out its original MANET subnet and enters the MANET subnet at MR1 place, receives the broadcast of MR1 place subnet; MR5 compares mobile network's prefix of this broadcast and own address, finds both differences, and then MR5 perceives oneself and has been in roaming state, has namely roamed in the nonlocal MANET network domains.

(2) the MR5 Care-of Address own new with the mobile network's prefix configuration of oneself according to the new AR address information that receives, simultaneously, its root router identity is learnt in Hello broadcasting according to MR1, MR1 is recorded to the root router tabulation, send binding update messages to its home agent HA 5 again, and the destination address of Binding Update bag is made as MR1, the configuration back broadcasting Binding Update bag that finishes.This Binding Update wraps in the MANET subnet and arrives MR1 according to the OLSR Routing Protocol.

(3) MR1 is sent to HA1 with the Binding Update bag by the MR1-HA1 bidirectional tunnel.

(4) HA1 is according to the destination address of Binding Update bag, the Binding Update bag is forwarded to its destination address HA5, it is HA1 that HA5 record Binding Update is wrapped a jumping routing iinformation, after Care-of Address CoA that MR5 is new is stored in Care-of Address CoA and home address HoA mapping table simultaneously, finish the Binding Update to MR5; After, HA5 receives the message that mails to MR5, and the reverse route during all by Binding Update bag next sends to MR5, and so far, MR5 finishes its binding registration renewal process.

Referring to Fig. 4, introduce the situation of the another kind of MR of the present invention and HA binding.In real network was disposed, a HA may manage a plurality of MR simultaneously.Among the present invention, if when the HA of the HA of root router and accesses network MR is identical, then the binding of this accesses network MR and its HA is more simple, and a need is through a tunnel encapsulation.Its detailed process is as follows:

Its step (1), (2), (3) are identical with the binding procedure of general MR shown in Figure 3 and HAD.

Step (4) arrives the home agent HA 5 of MR1 when the Binding Update request, HA5 checks the destination address of this request message, learn that its purpose home agent HA is exactly this node, handle so MR5 is carried out Binding Update: the Care-of Address of record MR5 adds Care-of Address and home address mapping table; Reverse route by the Binding Update request sends to MR5 with the Binding Update acknowledge message again, finishes whole Binding Update process.

In addition, nested mobile network internal node is as shown in Figure 2 communicated by letter with the Internet network node, also only needs to transmit through the tunnel of MR1-HA5.

Step 3 when each visit mobile node roams into new MANEMO subnet, is all registered reverse route by root router, substitutes visit mobile node and its home agent foundation binding by root router, sets up binding with Correspondent Node again, thereby realizes routing optimality.

In the basic supported protocol of network mobility and existing other nested mobile network routing optimality scheme, emphasis is improved all to be the registration binding procedure of mobile network's router, the visit mobile node is not optimized with communicating by letter of Correspondent Node.But the present invention has also carried out routing optimality to the communication process between visit mobile node and the Correspondent Node.Referring to Fig. 5, specifically introduce this communication route optimization process of the present invention:

(1) the visit mobile node is in moving process, periodically detect it and receive the MR broadcast message, if find that the MR address in the broadcast message is different with the MR address of oneself preserving, just perceive oneself and be in roaming state, just send reverse route registration request with own original home address to this new MR;

(2) this new MR receives the registration request of visit mobile node, verify its reasonability after, add own Care-of Address therein, send reverse route registration by the OLSR agreement to the own nearest root router of distance and ask;

(3) after root router is received reverse route requests, the routing iinformation of registration visit mobile node in reverse routing table: the Care-of Address of its home address and present MR thereof, and substitute the visit mobile node and make up the Binding Update request that sends VMH-HA to its HA: source address is the root router Care-of Address, and destination address is the HA of the VMH nearest apart from root router; The transmission course of binding update messages is identical with the transmission course of MR and HA binding: elder generation is sent to its home agent G-MRs HA by the bidirectional tunnel of the MR-HA of root router, and logical HA-HA bidirectional tunnel is sent to destination address VMNs HA, after this repeats no more again.

(4) after the home agent VMH HA of access node receives the Binding Update request, VMH information (Care-of Address of the root router of VMH_HA address and this binding update messages of generation) is stored in visit node user tabulation (VMH_HA-root router CoA mapping table), and generates the Binding Update acknowledge message that mails to VMH and root router;

(5) Correspondent Node sends packet to VMH in the network, and because the HA record of visit mobile node is arranged among the VMH_HA, VMH_HA just intercepts and captures all destination addresses in the network and is the packet of the VMH that exists in its VMH user list.

(6) VMH_HA is the packet of this VMH with the destination address of intercepting and capturing, and according to the information in this VMH user list, sends this packet the HA of root router to, transfers to root router again;

(7) root router receives the packet that VMH_HA sends, the analysis purpose address, and the reverse route according to this VMH in the reverse routing table sends packet to VMH; Simultaneously, root router substitutes VMH and sends the Binding Update request message to Correspondent Node, and the source address in this Binding Update request message is the Care-of Address of root router, and destination address is Correspondent Node.

(8) after Correspondent Node receives the Binding Update request, the VMH_HA address is stored in list of bindings, sends binding acknowledgement message to root router again; Root router then sends this VMH by its HA to VMH_HA and Correspondent Node is finished the message that binding is set up; So far, Correspondent Node and VMH finish binding foundation.

(9) VMH initiates communication to Correspondent Node, and packet is sent to root router by MR, and this communication process is identical with local stationary nodes, repeats no more herein.

(10) after, Correspondent Node and VMH need not to carry out forwarding through any home agent or VMH_HA just by the root router direct communication.

Referring to Fig. 6, the reverse routing table structure of introducing in the root router of the present invention is formed: be sequentially with following four fields, the implication of each field is as follows:

Src_VMN field: the home address HoA that initiates the visit mobile node VMN of reverse route registration request.In the present invention, VMN needn't apply for new Care-of Address, and will keep its original home address, sets up route and can reach condition by registering reverse route, to reduce the registration time delay of VMN in field network.

Src_MR field: the Care-of Address of MR that is used for the new NEMO subnet at the present place of record VMN.

Grounded_MR field: be used for the at present effective root router address of the new mobile network of record.This field is according to the only root router of the Information Selection address in its root router tabulation by src_MR.

Middle_MR (1-n) field: be used for this message repeating process of storage each MR address of process, as the constant transmissions path between VMN and the root router.

Referring to Fig. 7, introduce the structure of the root router tabulation of the non-root router maintenance of the present invention and form.It is provided with three fields, and the implication of each field is as follows:

The Ground_MR field is the Care-of Address CoA of root router, is used for the root router that record can receive its Hello message.

Hop_count is distance or the jumping figure that root router arrives this MR, with electing root router;

The hop_count field is for distance or the jumping figure of storage root router to this MR, with the important parameter of the root router that elects, the i.e. nearest root router of chosen distance.

Life_time (s) field is the effective time (be unit with the second) of root router clauses and subclauses.Initial time is 16 seconds, unwraps the beginning timing from the Hello that receives root router and successively decreases, and crosses this root router of after date and loses efficacy, must deletion.

Referring to Fig. 8, introduce the VMN user list structure composition that access node home agent VMN-HA of the present invention safeguards, it is sequentially with following four fields, and the implication of each field is as follows:

The VMN_list field is application and the HA address of the home agent VMN-HA Binding Update of this access node, substitutes this VMN nearest HA in its scope for root router and sends the Binding Update request.

The Ground_MR field is the root router address that sends the Binding Update request;

The Ground_HA field is the HA address of root router, and root router sends to its HA by the MR-HA bidirectional tunnel with the Binding Update request, is forwarded to backbone network again; Its HA sends to the Binding Update request by the HA-HA bidirectional tunnel home agent VMN-HA of this access node;

CN_ (1-N) field is the Correspondent Node CN address of having bound with this VMN, the CN address of this field store will VMN corresponding with it address to form mapping right, be used for the mapping table of filter module.If the VMN address is present in this VMN user list, and this CN address is in the CN_ of this VMN (1-n) field, and then this HA tackles its packet, and this CN is charged in CN_ (1-n) field; If the VMN address is present in this VMN user list, and this CN address also exists in CN_ (1-n) field of this VMN, does not then tackle this packet, because the root router of this moment has replaced VMN and this CN to set up direct binding.

The present invention has carried out repeatedly emulation and has implemented test, briefly introduces emulation below and implements result of the test:

(1) referring to Fig. 9, introduce when each mobile network node is received packet in the experimental network mean transit delay comparable situation of the packet of adding up:

Propagation delay time T _TransmissionComputing formula be that packet arrives destination time T _ArrivalDeduct packet generation time T _CreationPoor.As seen from Figure 9, the propagation delay time in the MANEMO network scenarios of the present invention is significantly less than the statistics that network mobility is supported NEMO BS protocol network scene substantially.This is because in the MANEMO scene, and the packet under the identical backbone network access point can directly be used the OLSR protocol transmission by MR, has saved MR nested transmission layer by layer and the encapsulation in each MR and HA tunnel thereof, has avoided many triangles route.And because OLSR perception mobile network topological structure, roaming node can directly select nearest root router to bind, and has saved the binding time of MR and HA.

In addition, violent in data wire in the NEMO BS agreement fluctuation fluctuation ratio MANEMO scene, this be because, the nested progression difference of each mobile network node/MR, the encapsulation number of times and the triangle route number of plies difference that experience in NEMO BS agreement scene are bigger.And in MANEMO scene of the present invention, avoided many triangles route substantially, the communication between the different backbone network access points only relates to the tunnel transmission of 2 HA at most, so the transmission time difference of each node data bag is minimum.

(2) referring to Figure 10, introduce the statistical magnitude of data packets for transmission in the experimental network:

Data packet number in the communication process has also reacted the quality of agreement, and simulation process has recorded the situation of packet in the communication process.As shown in figure 10, along with the increase of simulation time, the packet number also increases.Because the MANEMO network can not change the size of NEMO BS protocol data bag, so quantity of data packets has just directly reflected the data volume of communication process.As can be seen from Figure 10, obvious many than in the NEMO BS protocol network scene of data packets for transmission quantity in the MANEMO network scenarios, and also along with the passing of simulation time, advantage is more obvious.This is because in NEMO BS agreement, and packet is collided, destroys and lose easilier in the process of many triangles route and encapsulation layer by layer; And MANEMO method of the present invention has effectively been avoided many triangles route, has significantly reduced the operation of data encapsulation and decapsulation, has reduced propagation delay time, and these all make the transmission of packet more direct, effectively.As seen, MANEMO method of the present invention has increased the speed of transfer of data to the improvement of NEMO BS agreement, has improved communication efficiency.

(3) referring to Figure 11, introduce experimental network visit mobile node VMN and its home agent HA binding time delay relatively:

The binding time computing formula of VMN and its HA is: T _Binding=T _BUack– T _VMNreq, in the formula, T _{VMN Req}For the visit mobile node roams into first and the time of binding related news (being reverse route registration message in the present invention, is the message of application Care-of Address) in the MIRON scene, T that accesses network sends _BUackFor VMN receives the binding acknowledgement message time that HA sends.As shown in figure 11, the binding of VMN and its HA occurs in emulation and begins the back in the time of about 20 seconds, and the binding time of MIRON is about 0.5 second, and binding time of the present invention is about 0.36 second.

As can be seen from Figure, improve through optimization of the present invention, the binding time of VMN and its HA decreases, and reason is in the present invention, and VMN enters accesses network and no longer applies for new Care-of Address, but directly use its home address to set up reverse route to the MR application, thereby saved the time of application and the distribution of Care-of Address, simultaneously, VMN also need not to know its mobile status, use same home address from the beginning to the end, function is simplified.Therefore, the present invention is transferred to MR with above-mentioned part workload, has alleviated VMN self burden, and this, the limited VMN entity of battery life weak for computing capability are clear superiorities.

The above only is preferred embodiment of the present invention, and is in order to limit the present invention, within the spirit and principles in the present invention not all, any modification of making, is equal to replacement, improvement etc., all should be included within the scope of protection of the invention.

Claims (2)

1. routing optimization method with MANEMO mobile network system of nested mobile network routing optimality function is characterized in that described method comprises following operating procedure:

(1) each MR receives the identity information of couple in router periodic broadcast respectively, receives that the MR of same couple in router broadcast packet forms a MANET MANET that adopts the OLSR protocol communication each other, with the Care-of Address of MR as source address or destination address; Wherein, the MR that directly connects couple in router becomes root router, and the Ground Router flag scaling option in its Hello message is set to 1 automatically, and other MR of broadcast announcement;

When (2) Wai Di MR roams into new couple in router scope, set up Binding Update by the root router of its selection to home agent; This step further comprises following content of operation:

(21) the MR information of access route of finding its reception and own couple in router MR_Hello message perceive it and are in roaming state not simultaneously, just put out root router in order from all MR_Hello message of oneself reception and tabulate; This root router tabulation is provided with following three clauses and subclauses: be used for the Ground_MR field that record can receive the root router Care-of Address of its Hello message, be used for to select root router, the storage root router is to the distance of this MR or the hop_count field of jumping figure, is used for this root router clauses and subclauses of mark Life_time (s) field of effective time;

(22) roaming MR from root router tabulation, select the jumping figure minimum effective root router as destination address, the Binding Update request of itself and home agent is sent to root router by the OLSR agreement; Root router receives this Binding Update request, judge this News Category and continue and send: if this root router is different with the home agent of source MR, then this root router encapsulates this packet, be sent to the home agent of this root router by the bidirectional tunnel between MR and the home agent, be sent to the home agent of source MR again by the bidirectional tunnel between the home agent; If root router is identical with the home agent of source MR, then packet directly is sent to the purpose home agent by this root router;

When (3) each visit mobile node roams into new MANEMO subnet, all register reverse route by root router, substitute visit mobile node and its home agent foundation binding by root router, set up binding with Correspondent Node again, thereby realize routing optimality.

2. method according to claim 1, it is characterized in that: described step (3) further comprises following content of operation:

(31) the visit mobile node receives the broadcasting of new MR, perceives and lays oneself open to roaming state, just sends the registration request that comprises own home address to this new MR; This new MR receives the registration request of visit mobile node, behind the Care-of Address of interpolation therein oneself, sends reverse route registration request to the own nearest root router of distance; Root router is stored reverse routing table after receiving reverse route registration request;

(32) root router substitutes the visit mobile node and makes up Binding Update request with its home agent: source address is the root router Care-of Address, and destination address is the home agent of the access node nearest apart from root router;

(33) after the home agent of access node receives the Binding Update request, will visit mobile node information and be stored in the tabulation of visit node user, and make up the Binding Update acknowledge message that mails to the visit mobile node; Simultaneously, all destination addresses mail to the corresponding root router of this visit mobile node again for the packet of the visit mobile node of existence in its visit node user tabulation in the interception network;

(34) after root router received the Binding Update acknowledge message that the home agent of access node sends, the binding relationship of visit mobile node by the home agent of root router and access node just foundation finished;

(35) destination address that Correspondent Node sends in the network is for after the packet of visit mobile node intercepted and captured by the home agent of this access node, the home agent of this access node is according to the information in the tabulation of visit node user, send this packet the home agent of root router to, transfer to root router again;

(36) root router receives destination address that the home agent of access node sends and is the packet of visit mobile node, and the reverse route according to should the visit mobile node in the reverse routing table sends packet to the visit mobile node; Simultaneously, root router substitutes the bind-request message of visit mobile node structure and Correspondent Node, sends to Correspondent Node; After Correspondent Node receives this bind request, the home address of visiting mobile node is stored in list of bindings, sends binding acknowledgement message to root router again; So far, mobile network node and Correspondent Node are finished binding and are set up, and root router just sends this access node for the home agent of access node by its home agent and Correspondent Node is finished the message that binding is set up; After this, Correspondent Node just can pass through the root router direct communication with the visit mobile node, and the home agent that need not access node is carried out forwarding capability;

(37) home agent of access node receives access node and the correspondent node that the home agent of root router sends and finishes the message that binding is set up, Correspondent Node address in the message is stored in the Correspondent Node address field of this access node in the access node user list, and the mapping that generates this Correspondent Node address and this access node address is right, add in the mapping table of filter module, no longer tackle the packet that this Correspondent Node is issued this access node later on.

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