CN103152440A - Implement method of proxy mobile internet protocol version 6 (PMIP v 6) in evolution grouping system - Google Patents

Abstract

The invention discloses an implement method of a proxy mobile internet protocol version 6 (PMIP v 6) in an evolution grouping system and relates to the technical extension field of mobile internets. The implement method of the PMIP v 6 in the evolution grouping system comprises the following steps: deeply studying a PMIP v 6 standard defined by an internet engineering task force (IETF) in an electronic publishing system (EPS), studying a network layer mobility management protocol of the PMIP v 6, implementing the PMIP v 6 protocol based on open source software UMIP, in the process of implementing the PMIP v 6, firstly, combining the standard of the PMIP v 6 and existing modules of the UMIP, redesigning a software module of the PMIP v 6. And then definition of an important data structure of the PMIP v 6 is completed, and two functional entities of a macros generator (MAG) event handling process and a long mode active (LMA) event handling process are designed. Finally, each functional module is implemented. The PMIP v 6 is enabled to basically live up to a standard of IETF request for comments (RFC) 5213 and support a part of the third generation partnership project (3GGP) extension.

Description

The implementation method of PMIPv6 in a kind of evolved packet system

Technical field

The invention belongs to development of Mobile Internet technology expansion field, the particularly implementation method of PMIPv6 in a kind of evolved packet system.

Background technology

The rise of mobile Internet makes the mobile subscriber become than all urgent any time before to the bandwidth demand of communication network.3GPP plans to formulate the Radio Access Network of supporting higher rate at startup LTE, and has set up subsequently system architecture evolution (SAE) project so that existing network architecture is redesigned.The end result of project is to have released evolved packet system (EPS).EPS is an open system, and its core gateway and Mobility Management Entity can be supported other various non-3 GPP access network networks.EPS has adopted the network layer mobility management protocol that comprises two stack mobile IP v 6s, mobile IPv 4 and proxy mobile IPv 6 (PMIPv6) to come the mobility of support terminal in heterogeneous networks.

Many standardization bodies and researcher are studying PMIPv6, and wherein main standardization body comprises IETF, 3GPP and 3GPP2 etc.The present invention is by furtheing investigate the defined PMIPv6 standard of IETF, and with reference to the expansion of in EPS, standard P MIPv6 being done, on the basis of mobile IP v 6 open source software UMIP (USAGI-patched Mobile IPv6 for Linux), developed the PMIPv6 agreement.The agreement of developing is supported PMIPv6 signaling process and routing mechanism, supports part 3GPP expansion.

Summary of the invention

The objective of the invention is to propose the implementation method of PMIPv6 in a kind of evolved packet system, it is characterized in that, comprise: first is by the defined PMIPv6 standard of IETF is furtherd investigate, to the research of the network layer mobility management protocol of PMIPv6 in EPS; Second portion is the realization of basic PMIPv6 agreement;

1) key technology of EPS and PMIPv6

EPS is made of evolution block core (EPC) network and various Radio Access Network two large divisions, wherein the evolution block core net network provides and leads to the outer data network that comprises the Internet and the passage of Operator Specific Service (IMS network), be responsible for carrying out authentication functions, key agreement, follow the trail of the situation of movement of the inactive terminal of energy saver mode, and support mobile switching the between multiple different access technologies.Radio Access Network is responsible for comprising all activated terminals and wireless relevant function that transmits data;

Host-based network layer-two mobility management agreement in EPS, 3GPP has adopted the network layer mobility management protocol of two types of ietf definition in the EPC network: Host Based mobility management protocol and based on network proxy mobile IPv 6 agreement, wherein, the mobility management protocol of main frame is X2 stack mobile IP v 6 and mobile IPv 4; Keep the continuity of business when making terminal to move between different access technologies;

2) Design and implementation of PMIPv6 agreement is based on UMIP(mipv6-daemon-umip-0.4) the software realization,

(1) the realization mechanism analysis of UMIP

UMIP mainly is divided into mobile node (MN), home agent (HA) and three parts of Correspondent Node (CN), load the code of different piece by reading configuration file or input different parameters, realize difference in functionality, data structure Binding Update list (BUL) main in MIPv6 is deposited and is read by the mode of Hash with banding cache (BCE);

(2) modular design of PMIPv6

Be based on the mobility management protocol of network due to PMIPv6, MN is not needed to carry out any modification, although in PMIPv6, module in some MN has been reused in the realization of MAG, as the data structure of BUL, the processing of moving-head, but major part has all been done to revise and expand; The function of giving up MN and CN; And for the realization of LMA, some functions of having reused HA, and HA is made the corresponding changes and expand according to RFC5213.

The mobility management protocol of described main frame

1) mobile IPv 4 (MIPv4)

The mobile IPv 4 agreement is the mobility criteria that IETF formulates, and can allow mobile node momentarily connect under the existing network architecture and connects to the Net and can realize roaming in different sub-network.The mobile IPv 4 agreement does not need to change existing procotol, can make node use same IP address to be connected on any subnet, keeps existing communication in moving process;

2) mobile IP v 6

The concept of the mobile node in mobile IP v 6, home agent, home address and Care-of Address is identical with mobile IPv 4 or similar, but, mobile IP v 6 has absorbed again the advantage of many IPv6, mobile IPv 4 many improvement have been done, improve the ability that routing optimality function and dynamic home agent are found, provide the function of managing I Pv6 network mobility, so mobile IPv 6 protocol has than the mobile IPv 4 agreement and more manys advantage:

A) the mobile IPv 6 protocol IP address global for each mobile node has distributed, no matter they are connected on the Internet wherein, will reserve abundant IP address for the link of mobile node service to distribute cover (an at least one) Care-of Address to mobile node, in the situation that the IPv4 Address Run Short, it is unlikely reserving abundant global ip v4 address;

B) using appointing of IPv6 to broadcast the address makes certain node can send packet to some in these several systems of broadcasting the address arranged, mobile IPv 6 protocol effectively utilizes this principle to realize the dynamic home agent discovery mechanism, broadcast the address by the transmission Binding Update to appointing of home agent and come to obtain the response of most suitable from several home agent, IPv4 can't provide similar method;

C) use stateless address automatically after configuration and neighbor discovery mechanisms, mobile IPv 6 protocol neither needs DHCP also not need foreign agent on foreign link to configure the Care-of Address of mobile node;

D) mobile IPv 6 protocol can use IPSec for all safe requirements, as mandate, data integrity protection and replay protecting;

E) for fear of the waste of the bandwidth that causes due to the triangle route, mobile IPv 6 protocol has been specified the mechanism of routing optimality, and routing optimality is an additional function of mobile IPv 4, is but one of complete part of mobile IPv 6 protocol;

F) there are indivedual routers to carry out ingress filtering to the packet that they forward in the Internet, they check whether the packet that this source address is come should deliver to the interface that receives this packet, the mobile IP v 6 agreement can with this ingress filtering mode without any problems and deposit, a mobile node on foreign link uses its Care-of Address as the source address of packet, and its home address is included in its home address targets option, owing to being an effective address at the foreign link care of address, so packet will pass through ingress filtering smoothly.

The invention has the beneficial effects as follows evolved packet system (EPS) is being carried out on the basis of extensive investigation, draw PMIPv6 and have more the conclusion of advantage under EPS, on the basis of this research, furtherd investigate the key technology of PMIPv6, and realized the PMIPv6 agreement based on open source software UMIP, the PMIPv6 that realizes meets IETF RFC5213 standard substantially, and supports part 3GPP expansion.

Description of drawings

Fig. 1 is EPS network architecture diagram under non-roaming condition;

Fig. 2 is mobile IPv 4 figure;

Fig. 3 is the process chart of mobile IP v 6;

Fig. 4 is the basic network topology figure of PMIPv6;

Fig. 5 is that mobile node adheres to and the signaling process figure during attachment removal;

Fig. 6 is the modular design figure of PMIPv6;

Fig. 7 is the process chart of LMA when receiving PBU;

Embodiment

The present invention proposes the implementation method of PMIPv6 in a kind of evolved packet system, comprising: first is by the defined PMIPv6 standard of IETF is furtherd investigate, to the research of the network layer mobility management protocol of PMIPv6 in EPS; Second portion is the realization of basic PMIPv6 agreement; Be explained below in conjunction with accompanying drawing.

1, the key technology of EPS and PMIPv6

(1) EPS framework

Fig. 1 has provided the EPS framework in non-roaming situation, and in figure, EPS by evolution block core but (EPC) network and various Radio Access Network two large divisions consists of.Wherein the evolution block core net network provides the passage that leads to outer data network (as the Internet etc.) and Operator Specific Service (IMS network), be responsible for carrying out authentication functions, key agreement, follow the trail of the situation of movement of inactive terminal (for example terminal of energy saver mode), and support mobile switching the between multiple different access technologies.Radio Access Network is responsible for all activated terminals (for example transmitting the terminal of data) and wireless relevant function.Then the access point of the direct access of radio network of terminal obtains corresponding service by core net,

Several major function entities that evolution block core in the EPS framework (EPC) net is relevant: Mobility Management Entity (MME), gateway (S-GW), packet data network gateway (PDN GW), IAD (A-GW), evolution packet data gateway (ePDG).

(2) host-based network layer-two mobility management agreement in EPS

In order to make terminal to ask the continuity that keeps business in mobile at different access technologies, 3GPP has adopted the network layer mobility management protocol of two types of ietf definition in evolution block core (EPC) network: Host Based mobility management protocol (X2 stack mobile IP v 6, mobile IPv 4) and based on network mobility protocol (proxy mobile IPv 6).

1) mobile IPv 4 (MIPv4)

Figure 2 shows that framework and the process chart of mobile IPv 4, the mobile IPv 4 agreement is the mobility criteria that IETF formulates, and can allow mobile node momentarily connect under the existing network architecture and connects to the Net and can realize roaming in different sub-network.The mobile IPv 4 agreement does not need to change existing procotol, can make node use same IP address to be connected on any subnet, keeps existing communication in moving process.

2) mobile IP v 6 (MIPv6)

Figure 3 shows that the process chart of mobile IP v 6; Many concepts in mobile IP v 6 (MIPv6) are identical with mobile IPv 4 or similar, as mobile node, home agent, home address and Care-of Address etc.But, mobile IP v 6 has absorbed again the advantage of many IPv6, and mobile IPv 4 has been done many improvement, and the ability found of routing optimality function and dynamic home agent for example provides the function of managing I Pv6 network mobility.Mobile IPv 6 protocol has than the mobile IPv 4 agreement and more manys advantage:

A) the mobile IPv 6 protocol IP address global for each mobile node has distributed, no matter they are connected on the Internet wherein, will reserve abundant IP address for the link of mobile node service to distribute cover (an at least one) Care-of Address to mobile node, in the situation that the IPv4 Address Run Short, it is unlikely reserving abundant global ip v4 address;

B) using appointing of IPv6 to broadcast the address makes certain node can send packet to some in these several systems of broadcasting the address arranged, mobile IPv 6 protocol effectively utilizes this principle to realize the dynamic home agent discovery mechanism, broadcast the address by the transmission Binding Update to appointing of home agent and come to obtain the response of most suitable from several home agent, IPv4 can't provide similar method;

C) use stateless address automatically after configuration and neighbor discovery mechanisms, mobile IPv 6 protocol neither needs DHCP also not need foreign agent on foreign link to configure the Care-of Address of mobile node;

D) mobile IPv 6 protocol can use IPSec for all safe requirements, as mandate, data integrity protection and replay protecting;

E) for fear of the waste of the bandwidth that causes due to the triangle route, mobile IPv 6 protocol has been specified the mechanism of routing optimality, and routing optimality is an additional function of mobile IPv 4, is but one of complete part of mobile IPv 6 protocol;

F) there are indivedual routers to carry out ingress filtering to the packet that they forward in the Internet, they check whether the packet that this source address is come should deliver to the interface that receives this packet, the mobile IP v 6 agreement can with this ingress filtering mode without any problems and deposit, a mobile node on foreign link uses its Care-of Address as the source address of packet, and its home address is included in its home address targets option, owing to being an effective address at the foreign link care of address, so packet will pass through ingress filtering smoothly.

(3) host-based network layer-two mobility management agreement in EPS

EPS has also adopted a kind of based on network network layer mobility management protocol: proxy mobile IPv 6 (PMIPV6).PMIPv6 does not need terminal to carry out any change, and its target is when mobile node moves between a plurality of couple in routers, and the IP address can not change, i.e. mobile node itself and do not know that change has occured in its position, thus hidden mobility in network layer.Fig. 4 is the basic network topology of PMIPv6 definition.

Mainly comprise two kinds of new functional entitys in a PMIPv6 territory: local mobile anchor (LMA) and Mobile Access Gateway (MAG).The signaling procedure of PMIPv6 comprises mainly that mobile node adheres to, switching and attachment removal.

Provide and adhere to and the attachment removal signaling process, as shown in Figure 5.(MN) (initially adheres to or switches) when being attached to MAGl when mobile node, will send route request information to MAGI.MAGl is that MN creates a corresponding Binding Update list (BUL), and in order to allow corresponding LMA upgrade or create the positional information of this mobile node, MAGI will send an agent binding update (PBU) message to the LMA of this mobile node simultaneously.After LMA receives this message, will be responsible for mobile node and distribute home network prefix, and the loopback agent binding is replied (PBA) message.Simultaneously LMA upgrade the banding cache (BCE) of mobile node or for this reason mobile node create a BCE and set up bidirectional tunnel between one and MAG.MAGl receive can set up equally after PBA and LMA between bidirectional tunnel.So far, MAGl has obtained the home link that enough information is simulated mobile node, to allow mobile node discover mobility less than oneself.Last MAGl sends an advertising of route to mobile node, and mobile node is received the address prefix configuration of IP v6 address that will utilize after this advertising of route wherein, thereby completes the attaching process of PMIPv6 signaling.

When MN moves to MAG2 from MAGl, MAG2 will detect adhering to of MN equally, thereby repeat above-mentioned attaching process.And after MAGI will detect the attachment removal of MN, carrying out attachment removal flow process: MAGI, to send life span be that 0 PBU is to LMA, show this message for separating registration message, LMA will delete the information such as associated tunnel, route after receiving and separating registration message, and loopback PBA is to MAGl.

Compare with mobile mouthful, it is few that PMIPv6 has the interface-free resources of taking, terminal it goes without doing any modification, and handover delay and packet loss be the advantage such as smaller all, can estimate, will mainly adopt PMIPv6 as its network layer mobility management protocol in following EPS.

2, the Design and implementation of PMIPv6 agreement

Realized the PMIPv6 agreement based on mipv6-daemon-umip-0.4 (UMIP) software.This chapter paper the realization mechanism of UMIP, then provided the modular design of proxy mobile IPv 6, describe at last the specific implementation of key data structure, signaling procedure and each module of PMIPv6 in detail.

(1) the realization mechanism analysis of UMIP

UMIP mainly is divided into three parts: mobile node (MN), and home agent (HA), Correspondent Node (CN) by reading configuration file or inputting the code that different parameters loads different piece, is realized difference in functionality.Data structure Binding Update list (BUL) main in MIPv6 is deposited and is read by the mode of Hash with banding cache (BCE).

(2) modular design of PMIPv6

Be based on the mobility management protocol of network due to PMIPv6, MN is not needed to carry out any modification, therefore in UMIP, the function of MN and CN does not have too large reference value to the realization of PMIPv6.Although in PMIPv6, the module in some MN has been reused in the realization of MAG, as the data structure of BUL, the processing of moving-head.But major part has all been done to revise and expand.Because PMIPv6 does not support DynamicHost address discovery and routing optimality, so MN, these functions in CN will be rejected.And for the realization of LMA, some functions of having reused HA, and according to RFC5213, HA made the corresponding changes and expand, the functional entity that this paper realizes and module are as shown in Figure 6.

The module of design is introduced:

1) ICMP6 monitors processing threads: this module is an independently thread, is mainly used in coming detection node to adhere to by the monitoring to ICMPv6 message such as route requests (RS), helps MAG to realize the home network analog functuion of mobile node.

2) mobile node detection module: mainly be responsible for the Move Detection of mobile node, comprise that mobile node adheres to detection and attachment removal detects.This module is triggered by the ICMP6 processing threads.

3) mobile node authentication module: after the mobile node detection module detects mobile node and adheres to, will inform the mobile node authentication module, mobile node is authenticated, this module is based on the local policy file.

4) binding message watcher thread and processing module: MAG and LMA start this independent thread, open a moving-head socket in thread, monitor binding message.The message of receiving is utilized callback mechanism, and dissimilar message call respective function is processed, and triggers message processing module.In MAG, this module comprises that the structure of agent binding update (PBU) sends, agent binding update is replied the processing of (PBA), the maintenance of Binding Update list (BUL) etc.In LMA this module comprise that the processing of agent binding update (PBU), agent binding reply that the structure of (PBA) sends, the maintenance of banding cache entry (BCE) etc.This module will be called other as the tunnel management module in processing procedure, routing management module carries out the setting of user data face, carry out alternately with the task queue thread simultaneously, thereby overtime task is carried out respective handling.

5) task queue thread: for the transmission of the task that overtime requirement is arranged as (PBU), the maintenance of BUL all is kept in a task queue, and the task queue thread is responsible for specially and is safeguarded this formation, when having task overtime, call corresponding timeout treatment function.

6) tunnel management module: the tunnel management module is responsible for the management of bidirectional tunnel between MAG and LMA, comprises the foundation of bidirectional tunnel, the safeguarding of tunnel (statistics tunnel number of users, when number of users is 0, the deletion tunnel).

7) routing management module: routing management module mainly comprises the establishment deletion of route, the modification of routing rule, thereby make the data of mobile node under MAG can pass through corresponding tunnel, and the data that mail to this mobile node also can be intercepted and captured by its LMA, finally send to mobile node by the tunnel.

(3) realization of PMIPv6

Discuss the specific implementation of PMIPv6 from two aspects:

1) functional entity in the PMIPv6 agreement is the basis, tells about respectively important data structures and the software handling process of MAG and LMA.

Mainly comprise three kinds of handling processes under event in MAG, these three events are respectively MAG and detect that the terminal attachment removal is adhered to, detected to terminal and MAG receives PBA.

After MAG detects adhering to of MN, with the MN ID that obtains and MN is authenticated, if this MN is allowed to enjoy the PMIPv6 service, carry out the triggering of PBU.

After MAG receives PBA, will carry out Certificate Authority to LMA, then extract the moving-head of message, and check mobile option wherein.When the value of status field option is 128 (request is accepted) and other when all normal, MAG utilizes the IPv6 address prefix structure advertising of route message in home network address prefix option, sends to corresponding MN.

Handling process and realization after mobile node leaves detected in MAG, after MAG detects leaving of mobile node, will trigger and separate registration process.MAG identifies by mobile node and APN confirms whether adhere to before this MN, and if so, the PBU that builds life span and be O mails to LMA and separates registration.

In LMA, main data structure is banding cache (BCE), and this structure is to expand on the basis of the BCE of MIPv6, and main content is the relevant information of record move node and accompanying MAG thereof.

2) handling process of LMA

The handling process of LMA includes only processes this a kind of situation to the PBU event: after LMA receives PBU, at first will authenticate MAG, then process the PBU message header and check mobile option, if all normal words, LMA will be in BCE for this reason mobile node create or upgrade corresponding data and with create IP tunnel and route, send at last agent binding and confirm (PBA).

Fig. 7 is the process chart of LMA when receiving PBU; Handling process specifically describes as follows:

1) MAG authentication: obtain the MAG address by the PBU message of receiving, with the coupling of the mandate MAG address list in this MAG address and LMA, authenticate by matching result.Method is similar to above-mentioned LMA authentication.

2) after the processing of PBA message: LMA obtains the PBU of MAG transmission by the raw socket of monitoring, extract moving-head and corresponding mobile option is checked.If wrong, compose upper corresponding error code for the state mobile option.

3) to the operation of BCE: the PBU that receives separates registration message, must check that therefore life span judges, to take corresponding actions.Ask when being 0 when existence, illustrate that this message for separating registration message, should search corresponding information in BCE to delete, and when life span was not 0, this message was binding registration message, set up the corresponding information entry in BCE.

4) tunnel and routing management: when PBU message is binding registration, create corresponding tunnel and route.And when PBU message is the solution registration message, delete corresponding tunnel and route.

5) build and send PBA message: the mobile header of PBA message and PBU's is the same.Wherein mobile option is the same with mobile option in PBU message, and its definition can be referring to the definition of mobile option in PBU.After PBA constructs, send to MAG by raw socket.

Claims (2)

1. the implementation method of PMIPv6 in an evolved packet system, is characterized in that, comprising: first is by the defined PMIPv6 standard of IETF is furtherd investigate, to the research of the network layer mobility management protocol of PMIPv6 in EPS; Second portion is the realization of basic PMIPv6 agreement;

1) key technology of EPS and PMIPv6

EPS is made of evolution block core EPC network and various Radio Access Network two large divisions, wherein the evolution block core net network provides and leads to the outer data network that comprises the Internet and the passage of Operator Specific Service IMS network, be responsible for carrying out authentication functions, key agreement, follow the trail of the situation of movement of the inactive terminal of energy saver mode, and support mobile switching the between multiple different access technologies.Radio Access Network is responsible for comprising all activated terminals and wireless relevant function that transmits data;

Host-based network layer-two mobility management agreement in EPS, 3GPP has adopted the network layer mobility management protocol of two types of ietf definition in the EPC network: Host Based mobility management protocol and based on network proxy mobile IPv 6 agreement, wherein, the mobility management protocol of main frame is X2 stack mobile IP v 6 and mobile IPv 4; Keep the continuity of business when making terminal to move between different access technologies;

2) Design and implementation of PMIPv6 agreement is based on UMIP(mipv6-daemon-umip-0.4) the software realization,

(1) the realization mechanism analysis of UMIP

UMIP mainly is divided into mobile node MN, three parts of home agent HA and Correspondent Node CN, load the code of different piece by reading configuration file or input different parameters, realize difference in functionality, data structure Binding Update list BUL and banding cache BCE main in MIPv6 deposit and read by the mode of Hash;

(2) modular design of PMIPv6

Be based on the mobility management protocol of network due to PMIPv6, MN is not needed to carry out any modification, although in PMIPv6, module in some MN has been reused in the realization of MAG, as the data structure of BUL, the processing of moving-head, but major part has all been done to revise and expand; The function of giving up MN and CN; And for the realization of LMA, some functions of having reused HA, and HA is made the corresponding changes and expand according to RFC5213.

2. the implementation method of PMIPv6 in a kind of evolved packet system according to claim 1, is characterized in that the mobility management protocol of described main frame

1) mobile IPv 4

The mobile IPv 4 agreement is the mobility criteria that IETF formulates, can allow mobile node momentarily connect under the existing network architecture and connect to the Net and can realize roaming in different sub-network, the mobile IPv 4 agreement does not need to change existing procotol, can make node use same IP address to be connected on any subnet, keep existing communication in moving process;

2) mobile IP v 6

The concept of the mobile node in mobile IP v 6, home agent, home address and Care-of Address is identical with mobile IPv 4 or similar, but, mobile IP v 6 has absorbed again the advantage of many IPv6, mobile IPv 4 many improvement have been done, improve the ability that routing optimality function and dynamic home agent are found, provide the function of managing I Pv6 network mobility, so mobile IPv 6 protocol has than the mobile IPv 4 agreement and more manys advantage:

A) the mobile IPv 6 protocol IP address global for each mobile node has distributed, no matter they are connected on the Internet wherein, will reserve abundant IP address for the link of mobile node service to distribute cover (an at least one) Care-of Address to mobile node, in the situation that the IPv4 Address Run Short, it is unlikely reserving abundant global ip v4 address;

B) using appointing of IPv6 to broadcast the address makes certain node can send packet to some in these several systems of broadcasting the address arranged, mobile IPv 6 protocol effectively utilizes this principle to realize the dynamic home agent discovery mechanism, broadcast the address by the transmission Binding Update to appointing of home agent and come to obtain the response of most suitable from several home agent, IPv4 can't provide similar method;

C) use stateless address automatically after configuration and neighbor discovery mechanisms, mobile IPv 6 protocol neither needs DHCP also not need foreign agent on foreign link to configure the Care-of Address of mobile node;

D) mobile IPv 6 protocol can use IPSec for all safe requirements, as mandate, data integrity protection and replay protecting;

E) for fear of the waste of the bandwidth that causes due to the triangle route, mobile IPv 6 protocol has been specified the mechanism of routing optimality, and routing optimality is an additional function of mobile IPv 4, is but one of complete part of mobile IPv 6 protocol;

F) there are indivedual routers to carry out ingress filtering to the packet that they forward in the Internet, they check whether the packet that this source address is come should deliver to the interface that receives this packet, the mobile IP v 6 agreement can with this ingress filtering mode without any problems and deposit, a mobile node on foreign link uses its Care-of Address as the source address of packet, and its home address is included in its home address targets option, owing to being an effective address at the foreign link care of address, so packet will pass through ingress filtering smoothly.

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