WO2011069383A1

WO2011069383A1 - Method for realizing user mobility

Info

Publication number: WO2011069383A1
Application number: PCT/CN2010/077115
Authority: WO
Inventors: 胡方伟
Original assignee: 中兴通讯股份有限公司
Priority date: 2009-12-08
Filing date: 2010-09-19
Publication date: 2011-06-16
Also published as: CN102088390A; CN102088390B

Abstract

A method for realizing user mobility is disclosed by the present invention. In the method, an address is assigned for a mobile node, and a Transmission Control Protocol (TCP) connection of the mobile node is established according to the address; the address only identifies the mobile node identity attribute, which is showed by an Endhost Identity (EID) address; a network node encapsulates an IP message of the mobile node; the address of the IP message encapsulated only has location attribute, which is showed by a Routing Locator (RLOC) address. The method includes that a boundary tunnel router receives the IP message; the boundary tunnel router finds the RLOC address corresponding to the EID address of the IP message locally; the boundary tunnel router encapsulates the IP message with the RLOC address; the boundary tunnel router sends the IP message after encapsulation. According to the present invention, the user mobility can be realized simply.

Description

TECHNICAL FIELD The present invention relates to the field of communications, and in particular to a method for implementing user mobility. BACKGROUND OF THE INVENTION With the development of networks, there is an increasing demand for user mobility. The design of the Internet is considered in the fixed (wired) mode of access environment, and does not take into account the large amount of mobile users. Therefore, how to solve the problem of user mobility in the Internet is a hot topic of current research. Currently, for users in the Internet. Mobility schemes include protocols such as ΜΙΡν4, ΜΙΡνό, ΡΜΙΡν6, and most of these protocols are inadequate. MIPv4 and MIPv6 are host-based solutions that require certain changes to the host and can only be used for IPv4 networks and IPv6 networks, respectively. MIPv4 There is also a serious triangular routing problem with MIPv6. For the PMIPv6 protocol, the implementation of this protocol is more complicated and can only be used for networks with IPv6 addresses. The solution to the problem of solving user mobility problems in related technologies has not been proposed yet. An effective solution. The content of the invention is relevant The present invention has been made in view of a relatively complicated solution to the problem of user mobility in operation. Therefore, the main object of the present invention is to provide a method for implementing user mobility to solve at least one of the above problems. According to an aspect of the present invention, a method for implementing user mobility is provided. The method for implementing user mobility according to the present invention includes: assigning an address to a mobile node, and establishing a TCP connection of the mobile node by the address, the address Only the identity attribute of the mobile node is identified, and the identity attribute is represented by an EID address; the network node encapsulates the IP packet of the mobile node, and the address in the encapsulated IP packet has only the location attribute, and the location attribute is represented by the RLOC address. When the location of the mobile node changes, the value of the EID address does not change. Further, the EID address is the only one in the world. The network node encapsulates the mobile node's IP packet, including: the border tunnel router receives the IP address; the border tunnel router locally searches for the RLOC address corresponding to the EID address of the IP address; The tunnel router encapsulates the RLOC address for the IP address; the border tunnel router sends the encapsulated IP address. Further, in a case that the border tunnel router cannot find the RLOC address corresponding to the EID address locally, the method further includes: the border tunnel router sends a query message to the mapping system, where the mapping system is configured to store the EID address and the RLOC The mapping relationship of the address; the mapping system returns a response message to the border tunnel router, where the response message carries the RLOC address. Further, the mapping system is composed of a distributed mapping table server. Further, the border tunnel router includes: an ingress tunnel router and an egress tunnel router, where the ingress tunnel router searches for a mapping relationship between the EID address and the RLOC address; and the egress tunnel router registers and updates the mapping relationship between the EID address and the RLOC address. Further, in a process in which the border tunnel router sends the encapsulated IP address, if the location of the mobile node changes, the method further includes: the border tunnel router of the network where the mobile node is located sends a registration message to the mapping system, where The registration message is used to indicate that the location of the mobile node has changed; the mapping system adds an RLOC address entry to the mapping table of the EID address, and increases the mapping priority of the RLOC address. By means of the invention, the address assigned to the mobile node only identifies the identity attribute of the mobile node, wherein the identity attribute is represented by an terminal identifier (EID) address; the address of the IP 4 message only has a location attribute, a location attribute It is represented by a routing location (RLOC) address, which solves the complicated problem of solving the problem of user mobility in the related art, thereby achieving the effect of easily implementing user mobility. BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are set to illustrate,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,, In the drawings: FIG. 1 is a schematic diagram of a mapping system for user mobility according to an embodiment of the present invention; 2 is a flow chart showing a method for implementing user mobility according to an embodiment of the present invention; FIG. 3 is a flowchart of a mapping update mechanism according to an embodiment of the present invention; FIG. 4 is a schematic diagram of actively initiating communication according to an embodiment of the present invention. A flow chart of data forwarding when a user's location changes; FIG. 5 is a flow chart of data forwarding when a passively received user's location changes in accordance with an embodiment of the present invention. BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail with reference to the accompanying drawings. It should be noted that the embodiments in the present application and the features in the embodiments may be combined with each other without conflict. According to an embodiment of the present invention, a new method for implementing user mobility based on identity identification and location separation technology is first provided, in which a dual attribute of identity and location possessed by an IP address is separated and assigned to a mobile user. The address only identifies the identity attribute of the mobile user, and no longer has a location attribute. The address is used to establish a TCP connection. The address is represented by an Endpoint Identifiers (EID). The address assigned by the network part only identifies the location attribute. The user's identity attribute is also represented. The address is represented by a routing location (Routing Locator, RLOC for short), and is used for transmission of user data packets in the network. FIG. 1 is a schematic diagram of a user mobility mapping system according to an embodiment of the present invention. As shown in FIG. 1, a user mobility mapping system is implemented based on an identity identification and a location separation technology, and a mobile node accesses a network through a border tunnel router, and an exit tunnel. The border router ( ETR ) registers the user's information to the mapping system. When the location of the mobile node changes, the mobile node's information is registered with the mapping system through the new ETR. The mapping system consists of a Distribute Hast Table (DHT) mapping server. In an actual application, the method for implementing user mobility is identified by an attribute, where an address is assigned to a mobile node (ie, a mobile user), and a TCP connection of the mobile node is established through the address, and the address is only identified. The identity attribute of the mobile node, the identity attribute is represented by an terminal identifier (EID) address; the network node (which may include a border tunnel router, a mapping system) configures and transmits the IP packet of the mobile node, and the configured IP packet The address at the time of transmission in the text only has a location attribute, which is represented by a Route Location (RLOC) address. In this embodiment, the location attribute and the identity attribute of the mobile node are separately represented, and are respectively represented by different identifiers or addresses, thereby solving the problem that the solution for solving the user mobility problem in the related art is complicated, and thus can be simplified. Realize the mobility of users. Preferably, when the location of the mobile node changes, the value of the EID address of the mobile node does not change. With this method, user mobility can be achieved more easily. Preferably, the EID address is globally unique. With this method, user mobility can be achieved more easily. 2 is a schematic flowchart of a method for implementing user mobility according to an embodiment of the present invention. The method includes the following steps: step S202 to step 4: S2: Step 4: S202, border tunnel router (including an ingress tunnel router and an egress tunnel router) Receiving an IP address; in step S204, the border tunnel router locally searches for the RLOC address corresponding to the EID address in the IP address; and in step S206, the border tunnel router encapsulates the RLOC address in the IP address; Step S208, the boundary tunnel The router sends the encapsulated IP packet. The implementation process of the embodiment of the present invention will be described in detail below with reference to examples. The technology based on identity and location separation needs to consider two aspects of user mobility. One is the mapping update mechanism after the location of the mobile user changes, and the other is the data forwarding process of the mobile node. A flowchart of a mapping update mechanism for implementing user mobility based on identity and location separation techniques is shown in FIG. FIG. 3 is a flowchart of a mapping update mechanism according to an embodiment of the present invention. The method steps are as follows: Step S301: In an initial state, a mobile node (MN) registers with the mapping system through ETR1, and when ETR1 detects that the mobile node is attached, it finds There is a new EID identifier, a mechanism for registering with the mapping system, and a map-register (Map-Register) message. The content of the file contains the EID identifier and the RLOC 1 address of ETR1. The priority of the mapping relationship between the two is priority. Step S302: After receiving the mapping registration message, the DHT mapping server in the mapping system stores the mapping relationship between the EID and the RLOC1 to the specific DHT mapping service according to the DHT algorithm. , and start the timer. After the timer expires, the DHT mapping server invalidates the mapping relationship; Step S303, when the location of the mobile node changes, the mobile node accesses the network through the new border tunnel router ETR2, and needs to perform EID again. Registration. ETR2 will initiate a new registration mechanism to the mapping system, encapsulating Map-Register (ie, mapping registration) messages. Because the location of the mobile node changes, its EID value does not change. Therefore, the message content contains the EID identifier and the new RLOC address RLOC2 of ETR2, and the mapping relationship between the two is priority2. In order to ensure that the mobile node can quickly switch to the new path after the location changes, the priority of the mapping between the EID identifier and the RLOC2 is temporarily increased in the Map-Register 4 message and at least one timer is invalid. The priority of the increased time must be higher than the priority priority1 of the mapping relationship before the change of the mobile node; in step S304, after the mapping system receives the registration message, the mapping table of the EID is added with a new entry of the RLOC2, and Since the mapping priority of RLOC2 is temporarily raised, it is ensured that RLOC2 is preferred, and the mapping relationship is updated and switched after the location change of the mobile node is completed. The case where the mobile user changes is divided into two cases where the position of the user who initiated the communication changes and the position of the user who passively receives changes. The following two cases are respectively described. Case 1: The data forwarding process when the location of the user actively initiating communication changes: FIG. 4 is a flowchart of data forwarding when the location of the user actively initiating communication changes according to an embodiment of the present invention, and the method includes the following steps: Step 4 In the S401, the host A (hostA) initiates communication with the host B (hostB), and the host A encapsulates and sends the IP address, and the source IP address and the destination IP address of the host A are the EID address EIDa and the host B of the host A respectively. EID address EIDb; Step S402, after the message arrives at the ingress tunnel router (ITR1) of the host A (ie, the mobile user or the mobile node), the ITR1 locally searches for the RLOCb corresponding to the EIDb of the host B, and directly finds the mapping relationship. The encapsulated packet is encapsulated with an IP packet outside the original IP packet. The source IP address and the destination IP address are the RLOC1 address of ITR1 and the RLOCb address of the ETR. If the mapping relationship of the EIDb is not found in the local cache of the ITR, the query operation is initiated to the mapping system; in step S403, the mapping system replies to the Map-Reply after receiving the query (Map-Request) In the text, the Map-Reply 4 message carries the RLOCb address, and the ITR receives the Map-Reply 4 message and encapsulates the message; Step S404, forwards the encapsulated message to the ETR; Step S405, the forwarded encapsulated message is in the ETR Decapsulating the original message, and then sending the original message to the host B to complete the communication; Step S406, when the location of the host A is changed, the updated host address A1 is obtained, and the updated host A1 sends the message. The message arrives at the new ingress tunnel router (ITR2); in step S407, the new ingress tunnel router ITR2 registers the mapping relationship between the new EID and RLOC2 to the mapping system. According to the registration mechanism described above, the priority of the mapping relationship will be The priority of the mapping relationship between the EID and the RLOC1 is exceeded. Step S408: The outer layer encapsulation of the packet is performed on the ITR2, and the source IP address and the destination address of the outer packet are the RLOC2 address of the ITR2 and the address RLOCb of the ETR, respectively. The message is forwarded to the ETR device according to the RLOCb in the core network; in step S409, after receiving the encapsulated message, the ETR finds the mapping relationship between the new EID and the RLOC2, saves it in the local cache, and marks it. Then, the encapsulated packet is decapsulated and the decapsulated IP4 file is forwarded to the host B. In step S410, the host B replies with the message to the ETR. Step S411, 4艮 arrives at the ETR, and the identifier is found in the ETR. After the mapping between the EID address and the RLOC address, the process of requesting the mapping system is initiated; Step S412, because the mapping relationship corresponding to the EID in the mapping system includes RLOC1 and

RLOC2, and the priority of RLOC2 is higher than the priority of RLOC1. After receiving the Map-Reply message, the ETR will encapsulate according to the address of RLOC2; Step S413, ETR forwards the encapsulated IP4 message to the new one. The ITR2 address; Step S414, the new ingress tunnel router ITR2 address forwards the decapsulated IP4 message to the destination host A, and completes the switching of the traffic to the new location. Throughout the process, the EID address used to establish a TCP connection between hosts does not change, ensuring that the TCP connection is not interrupted. Case 2: The process of data forwarding when the passively received user location moves: FIG. 5 is a flowchart of data forwarding when a passively received user location changes according to an embodiment of the present invention. The method includes the following steps: Steps S501 to S505, the initial data flow process is the same as the user movement of the active communication, detailed The content is the same as the step S401 to the step S405; the step 4 is gathered S506, after the passive user (ie, the host B) moves, the 4艮 message initiated by the host A cannot be forwarded to the destination host B after reaching the ETR, and the ETR will send a The ICMP message with the destination address being unreachable is sent to the ITR1. Step S507: After receiving the ICMP message with the unreachable destination address, the ITR1 initiates a mapping request to the mapping system to obtain a mapping relationship between the new EID and the RLOC. Step S508, ITR1 After receiving the Map-Reply message, the packet is encapsulated according to the new RLOC2 address; in step S509, the ITR1 forwards the newly encapsulated RLOC address to the new ETR2 device; Step S510, the decapsulated by the ETR2 device The IP packet is forwarded to host B. When the traffic is switched to the new location, the TCP connection will not be interrupted, but a small amount of packet loss will occur. The present invention is applicable to a slow-moving device and does not have a great impact on the service. Preferably, the present invention proposes a new method for realizing user mobility based on identity identification and location separation technology, which separates the dual attributes of the identity and location of the IP address, and the address assigned by the mobile node only identifies the identity of the mobile node. The attribute, represented by EID, and the address assigned by the network node only identifies the location attribute, represented by RLOC. A border tunnel router (TR) is introduced between the user and the core network, and operations such as registration, searching, and updating of the EID and RLOC mapping relationships are performed on the router. Construct a new mapping system for storing the mapping between EID and RLOC. Preferably, the EID address identifying the identity attribute of the mobile node must be globally unique, and the value of the EID address is always unchanged when the location of the mobile node changes; and the value of the RLOC address is changed when the location of the mobile node changes. As the location of the mobile node changes, the border tunnel router (TR) is divided into an ingress tunnel router (ITR) and an egress tunnel router (ETR). The router completes the lookup operation of the EID and RLOC mapping relationship, and the egress tunnel router completes the registration and update operations of the EID and RLOC mapping relationship. Preferably, the mapping system is composed of a DHT mapping server, and the DHT mapping server may be a router running the DHT protocol or a DHT server. As can be seen from the above description, compared with the prior art, the present invention uses the address assigned to the mobile node to identify only the identity attribute of the mobile node, wherein the identity attribute is represented by an terminal identifier (EID) address; IP 4 The address of the transmission text only has the location attribute, and the location attribute is represented by the routing location (RLOC) address, which solves the complicated problem of solving the user mobility problem in the related art, thereby achieving the user mobility easily. Effect. Obviously, those skilled in the art should understand that the above modules or steps of the present invention can be implemented by a general-purpose computing device, which can be concentrated on a single computing device or distributed over a network composed of multiple computing devices. Alternatively, they may be implemented by program code executable by the computing device, such that they may be stored in the storage device by the computing device, or they may be separately fabricated into individual integrated circuit modules, or they may be Multiple modules or steps are made into a single integrated circuit module. Thus, the invention is not limited to any specific combination of hardware and software. The above is only the preferred embodiment of the present invention, and is not intended to limit the present invention, and various modifications and changes can be made to the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the scope of the present invention are intended to be included within the scope of the present invention.

Claims

Claim

A method for implementing user mobility, comprising:

Assigning an address to the mobile node, establishing a TCP connection of the mobile node by using the address, the address only identifying an identity attribute of the mobile node, and the identity attribute is represented by a terminal identifier EID address;

The network node encapsulates the IP address of the mobile node, and the encapsulated address of the IP address has only a location attribute, and the location attribute is represented by a routing location RLOC address.

2. The method according to claim 1, wherein the value of the EID address does not change when the location of the mobile node changes.

3. The method of claim 1 wherein the EID address is globally unique.

The method according to claim 1, wherein the network node encapsulating the IP address of the mobile node comprises:

The border tunnel router receives the IP packet;

The border tunnel router locally searches for the RLOC address corresponding to the EID address of the IP address;

The border tunnel router installs the RLOC address to the IP address; the border tunnel router sends the encapsulated IP packet.

The method according to claim 4, wherein, in a case that the border tunnel router cannot find the RLOC address corresponding to the EID address locally, the method further includes: the border tunnel router The mapping system sends a query message, where the mapping system is configured to store a mapping relationship between the EID address and the RLOC address;

The mapping system returns a response message to the border tunnel router, where the response message carries the RLOC address.

6. The method according to claim 5, wherein the mapping system is composed of a distributed mapping table server. The method according to claim 4, wherein the border tunnel router comprises: an ingress tunnel router and an egress tunnel router, wherein the ingress tunnel router searches for a mapping relationship between the EID address and the RLOC address;

The egress tunnel router registers and updates the mapping relationship between the EID address and the RLOC address. The method according to any one of claims 4 to 7, wherein in the process of transmitting the encapsulated IP4 message by the border tunnel router, if the location of the mobile node changes, The method also includes:

The border tunneling router of the network where the mobile node is located sends a registration message to the mapping system, where the registration message is used to indicate that the location of the mobile node changes; the mapping system is a mapping table of the EID address. The RLOC address entry is incremented and the mapping priority of the RLOC address is increased.