CN100512172C - Method for, realizing self adaption extension domain management entity mechanism Flexible IP network technology system - Google Patents

Abstract

A method for implementing an adaptive extended domain management entity mechanism in a flexible IP network technology system, the method is: when the network access point of a mobile node is switched to another link, the address of the extended domain management entity is obtained through proxy discovery, Judging whether it and the extended domain management entity belong to the same network segment, if yes, construct a registration request packet according to the traditional mobile IP principle, and send the extended domain management entity to forward the registration request; if not, obtain relevant information, construct an original socket, and Send a registration request to the extended domain management entity; the mobile node informs the basic domain management entity of its care-of address through registration; a bidirectional tunnel is established between the extended domain management entity and the basic domain management entity; the extended domain management entity generates a proxy ARP for the mobile node Entries to enable the proxy ARP mechanism for successfully registered mobile nodes. The invention solves the technical problems that the traditional mobile IP foreign agent entity performs the full agent function, resulting in reduced communication efficiency and occupying the system resources of the foreign agent entity.

Description

A method for realizing adaptive extended domain management entity mechanism in a flexible IP network technology system

technical field

The invention relates to a method for performing data communication after a mobile node roams to an extended network domain in a flexible IP network technology system. That is, it relates to a method in which the mobile node communicates with the extended domain management entity and the extended domain management entity acts as a proxy for the mobile node when the mobile node roams to a network different from its own network address. It specifically relates to a method for realizing an adaptive extended domain management entity mechanism in a flexible IP network technology system.

Background technique

With the development of computer networks and the improvement of the size, weight and performance of portable tools such as notebook computers and PDAs, the realization of mobile office has gradually become easier. Mobile IP technology is a technology derived from a series of standards developed by IETF to expand the mobility of IP networks. It is a technology that enables mobile nodes connected to any network to use the identity of their home address to continuously receive IP packets.

The mobile node roams from the home network to the foreign network. If the mobile node roams to a network with the same IP address as its own network segment, the mobile node can directly register with the foreign agent through agent discovery, and the mobile node will send an ARP broadcast request to the foreign network. The MAC address of the agent entity; the foreign agent entity responds to the ARP request; the mobile node sends the registration request to the foreign agent entity.

If the mobile node roams to a network segment different from its own IP address, because the IP address of the foreign agent entity and the IP address of the mobile node are not in the same network segment, according to the working principle of the TCP/IP network protocol stack, when the mobile node When requesting the destination host of another network segment, the mobile node will first send an ARP request to inquire about the MAC address of its gateway. Since the MAC address inquired by the mobile node is the MAC address of the home network gateway, no ARP response can be obtained. A mobile node cannot send a registration request to a foreign agent entity.

In order to solve the above problems, the foreign agent entity in the traditional mobile IP will perform the function of the full agent, and it will respond to all ARP requests, and then determine the routing and forwarding of the data packet according to its own routing information. In this way, it has a great impact on the foreign network. The full proxy function of the foreign agent entity makes the normal communication and access between the foreign network hosts one more hop, which reduces the communication efficiency of two foreign hosts that originally communicated normally, and even interrupts the communication between them in severe cases. The full proxy function of the foreign agent entity also occupies the system resources of the foreign agent entity, which greatly reduces the efficiency of the foreign agent entity in processing data.

Contents of the invention

The purpose of the present invention is to provide a method for implementing the self-adaptive extended domain management entity mechanism in the flexible IP network technology system, which solves the problem that the traditional mobile IP foreign agent entity in the background technology performs the function of full agent, resulting in two original normal The communication efficiency of the communicating foreign host is reduced or even interrupted, and the technical problem of occupying the system resources of the foreign agent entity.

Technical solution of the present invention is:

A method for implementing an adaptive extended domain management entity mechanism in a flexible IP network technology system, which is special in that: the method includes the following steps

1). When the network access point of the mobile node 5 is switched from one link to another link, the mobile node 5 obtains the address of the extended domain management entity 3 from the broadcast of the extended domain management entity 3 through "agent discovery";

2). The mobile node 5 judges whether it and the extended domain management entity 3 belong to the same network segment:

Yes, then the mobile node 5 constructs a registration request packet according to the principle of traditional mobile IP, and sends it to the extended domain management entity 3, and the extended domain management entity 3 forwards the registration request;

No, then the mobile node 5 obtains the IP address and the MAC address information of the extended domain management entity 3 from the broadcast of the extended domain management entity 3, constructs an original socket, and uses the original socket to send a registration request to the extended domain management entity 3;

3). Through the registration process, the mobile node 5 informs the basic domain management entity 1 of its own care-of address;

4). After the extended domain management entity 3 receives the correct registration response, it forwards it to the mobile node 5. At the same time, a bidirectional tunnel is established between the extended domain management entity 3 and the basic domain management entity 1;

5). The extended domain management entity 3 generates a proxy ARP entry for the mobile node 5, and enables the proxy ARP mechanism for the successfully registered mobile node 5, so that the mobile node 5 can access basic network domain resources or/and other mobile nodes 5.

The above-mentioned mobile node 5 can obtain the address of the extended domain management entity 3 from the broadcast of the extended domain management entity 3 through "agent discovery", which means that the extended domain management entity 3 sends periodic proxy broadcast messages, and the mobile node 5 receives the extended domain management entity 3 address. The proxy broadcast of the management entity 3, by comparing with the address of the basic domain management entity 1, the mobile node 5 detects that it is on the extended network domain link, and the mobile node 5 uses the address of the extended domain management entity 3 as its care-of address.

The above registration process refers to: after the extended domain management entity 3 receives the registration request of the mobile node 5, it forwards the registration request to the basic domain management entity 1 of the mobile node 5, and the basic domain management entity 1 authenticates the identity of the mobile node 5, Returns a registration response.

The above agent discovery means that the agent search mechanism can enable the mobile node 5 to detect whether it is on the basic network domain link or the extended network domain link, and when the mobile node 5 moves to a new network link, the agent discovery The mechanism can find a suitable extended domain management entity 3 for it.

The above-mentioned tunnel refers to the logical path through which the encapsulated data packet passes when it is transmitted on the public Internet.

The above-mentioned mobile node 5 refers to a device that can switch the position of accessing the Internet from one link to another, while still maintaining all ongoing communications, and only using the original fixed IP address.

The above-mentioned basic domain management entity 1 refers to a device that has a port connected to the basic network domain link of the mobile node 5 and provides identity authentication and proxy ARP network for the roaming mobile node 5 .

The above-mentioned extended domain management entity 3 may be a network device that forwards registration messages and data packets for the mobile node 5 on the extended network domain link of the mobile node 5 .

The above-mentioned flexible IP network technical system may be composed of a basic domain management entity 1, an extended domain management entity 3, and an access management entity 2; the above-mentioned access management entity 2 may be located between the basic domain management entity 1 and the extended domain management entity 3, A network device with an Internet-routable IP address that registers messages and forwards packets.

The present invention has the following advantages:

With the present invention, under different network environments, the flexible IP network technology system can identify and respond to the current network environment, execute the corresponding registration process and execute the corresponding tunnel module.

1. The present invention has no influence on the communication efficiency of the foreign hosts in normal communication;

2. It does not occupy the system resources of the extended domain management entity, and has no impact on the data processing efficiency of the extended domain management entity;

3. When the mobile node is roaming across the Internet, the mobile node can register successfully, and the extended domain management entity can still correctly respond to the ARP request of the mobile node.

Description of drawings

Fig. 1 is a topological diagram of the flexible IP network technology system of the present invention;

Fig. 2 is the establishment flowchart of the extended domain management entity of the present invention;

Fig. 3 is the broadcast packet format of the extended domain management entity in the present invention.

Description of reference numbers: 1—basic domain management entity, 2—access management entity, 3—extended domain management entity, 4—basic network domain user, 5—mobile node, 6—NAT, referring to the NAT of the basic network domain, 7 —Internet, namely the Internet, 8—NAT, refers to the NAT of the extended network domain.

Detailed ways

The flexible IP network technology system of the present invention refers to a system composed of a basic domain management entity 1, an extended domain management entity 3, and an access management entity 2, which enables the mobile node 5 to communicate normally using the original IP address in the extended network domain link system.

The invention utilizes the original socket and proxy ARP technology to realize the successful registration of the mobile node and the correct proxy of the mobile node by the extended domain management entity 3 when the mobile node roams in different network segments. That is, after the mobile node 5 roams across the Internet, the mobile node 5 sends a registration request to its extended domain management entity 3, and the mobile node 5 can register normally. After the registration is successful, the extended domain management entity 3 can correctly respond to the mobile node 5 ARP requests.

Implementation method of the present invention is as follows:

1. When the network access point of the mobile node 5 is switched from one link to another link, that is, on the extended network domain, after the "agent discovery" of the mobile node 5, the mobile node 5 obtains from the broadcast of the extended domain management entity 3 The address of the extended domain management entity 3;

2. The mobile node 5 judges whether it and the extended domain management entity 3 belong to the same network segment: if it belongs to the address of the same network segment, the mobile node 5 constructs a general registration request packet to the extended domain management entity according to the principle of traditional mobile IP 3, and the extended domain management entity 3 forwards the registration request. If they do not belong to the same network segment, the mobile node 5 obtains the IP address and the MAC address information of the extended domain management entity 3 from the broadcast of the extended domain management entity 3, and the mobile node 5 constructs an original socket, and uses the original socket to directly send a message to the extended domain. The management entity 3 sends a registration request. Such a registration request can be sent to the extended domain management entity 3 because raw sockets are used. Through the registration process, the mobile node 5 informs the basic domain management entity 1 of its own care-of address. After successful registration, a tunnel is established between the basic domain management entity 1 and the extended domain management entity 3 . The extended domain management entity 3 enables the mobile node 5 to normally access basic network domain resources and other mobile nodes 5 according to the proxy ARP mechanism.

Referring to Figures 1-3, the specific implementation method of the present invention is described in detail as follows:

1. Proxy discovery process: the extended domain management entity 3 sends a periodic proxy broadcast message, and the mobile node 5 receives the proxy broadcast from the extended domain management entity 3. By comparing with the address of the basic domain management entity 1, the mobile node 5 detects it On the extended network domain link, the mobile node 5 will use the address of the extended domain management entity 3 as its care-of address. See attached drawing 1.

2. The mobile node 5 receives the proxy broadcast from the extended domain management entity 3, and the mobile node 5 parses the proxy broadcast. Through comparison and analysis, the mobile node 5 detects whether it and the extended domain management entity 3 are in the same network segment. Refer to FIG. 3 for the broadcast packet format of the extended domain management entity 3 .

1) If the mobile node 5 and the extended domain management entity 3 belong to the same network segment: the mobile node 5 constructs a general registration request packet and sends it to the extended domain management entity 3 according to the principle of traditional mobile IP, and the extended domain management entity 3 forwards the registration request ;

2) If the mobile node 5 and the extended domain management entity 3 belong to different network segments: the mobile node 5 constructs a raw socket, and uses the raw socket to send a registration request message.

3. After the extended domain management entity 3 receives the registration request from the mobile node 5, it forwards the registration request to the basic domain management entity 1 of the mobile node 5, and the basic domain management entity 1 authenticates the identity of the mobile node 5 and returns a registration response.

4. After receiving the correct registration response, the extended domain management entity 3 forwards it to the mobile node 5, and at the same time, the extended domain management entity 3 generates a proxy ARP entry for the mobile node 5. A tunnel is established between the extended domain management entity 3 and the basic domain management entity 1, so that the mobile node 5 can still work normally after roaming. Refer to FIG. 2 for the establishment process of the extended domain management entity 3 .

5. Because the extended domain management entity 3 has added the proxy ARP entry of the mobile node 5, the extended domain management entity 3 will respond to the ARP response sent from the mobile node 5 to the ARP request.

Explanation of relevant technical terms of the present invention:

Basic domain management entity: a network device with a port connected to the basic network domain where the mobile node resides, providing authority authentication and identity proxy for the roaming mobile node.

Extended domain management entity: a network device on the extended network domain of the mobile node, which forwards identity authentication messages and data packets for the mobile node.

Access management entity: a network device with an IP address that can be routed on the Internet, it is located between the basic domain management entity and the extended domain management entity, and is a relay device that authenticates the identity of the mobile node and forwards the data packet of the mobile node.

Basic network domain: the network where the mobile node resides before roaming.

Extended network domain: the network reached by the mobile node after roaming.

IP tunnel: refers to the path through which an IP-based data packet is encapsulated in the payload of another IP data packet for transmission.

Tunnel technology: refers to the whole process including data encapsulation, transmission and unpacking.

Mobile node: A device that can switch the location of access to the Internet from one link to another, while still maintaining all ongoing communications, and only using the original fixed IP address.

Care-of address: The legal IP address obtained by the mobile node in the extended network domain.

IETF: Internet Engineering Task Force, Internet Engineering Task Force.

Full proxy: ARP response is given for all received ARP requests, not only for specific ARP requests.

Claims (9)

1. A method for implementing an adaptive extended domain management entity mechanism in a flexible IP network technology system, characterized in that: the method includes the following steps 1). When the network access point of the mobile node (5) switches from one link to another link, the mobile node (5) obtains the extended domain from the broadcast of the extended domain management entity (3) through "agent discovery" the address of the managing entity (3); 2). The mobile node (5) judges whether it and the extended domain management entity (3) belong to the same network segment: Yes, then the mobile node (5) constructs a registration request packet according to the principle of traditional mobile IP, and sends it to the extended domain management entity (3), and the extended domain management entity (3) forwards the registration request; No, then the mobile node (5) obtains the IP address and the MAC address information of the extended domain management entity (3) from the broadcast of the extended domain management entity (3), constructs the original socket, and uses the original socket to report to the extended domain management Entity (3) sends a registration request; 3). Through the registration process, the mobile node (5) informs the basic domain management entity (1) of its own care-of address; 4). After the extended domain management entity (3) receives the correct registration response, it forwards it to the mobile node (5). At the same time, a bidirectional tunnel is established between the extended domain management entity (3) and the basic domain management entity (1); 5). The extended domain management entity (3) generates a proxy ARP entry for the mobile node (5), and enables the proxy ARP mechanism for the successfully registered mobile node (5), so that the mobile node (5) can access basic network domain resources or / and other mobile nodes (5); The agent discovery means that the agent search mechanism can enable the mobile node (5) to detect whether it is on the basic network domain link or the extended network domain link. 2. the method for realizing the self-adaptive extended domain management entity mechanism in the flexible IP network technology system according to claim 1, is characterized in that: described mobile node (5) can be obtained from the extended domain management entity by "agent discovery" (3) Obtaining the address of the extended domain management entity (3) in the broadcast refers to: the extended domain management entity (3) sends a periodic proxy broadcast message, and the mobile node (5) receives the proxy broadcast of the extended domain management entity (3) , by comparing with the address of the basic domain management entity (1), the mobile node (5) detects that it is on the extended network domain link, and the mobile node (5) uses the address of the extended domain management entity (3) as its care-of address. 3. according to the method for realizing self-adaptive extended domain management entity mechanism in the flexible IP network technical system described in claim 1 or 2, it is characterized in that: described registration process refers to: the extended domain management entity (3) receives mobile After the registration request of the node (5), the registration request is forwarded to the basic domain management entity (1) of the mobile node (5), and the basic domain management entity (1) authenticates the identity of the mobile node (5), and returns a registration response. 4. the method for realizing the self-adaptive extended domain management entity mechanism in the flexible IP network technology system according to claim 3, is characterized in that: described agent discovers and refers to that agent search mechanism can make mobile node (5) detect its Whether it is on the basic network domain link or the extended network domain link, and when the mobile node (5) moves to a new network link, the agent discovery mechanism can find a suitable extended domain management entity (3 ). 5. the method for realizing the self-adaptive extended domain management entity mechanism in the flexible IP network technology system according to claim 4, is characterized in that: described tunnel refers to the data packet that is encapsulated passes through when transmitting on the public Internet logical path. 6. The method for realizing the self-adaptive extended domain management entity mechanism in the flexible IP network technology system according to claim 5, is characterized in that: described mobile node (5) refers to the position that can access Internet from a chain switch to another link, while still maintaining all ongoing communications, and only using devices with original fixed IP addresses. 7. the method for realizing self-adaptive extended domain management entity mechanism in the flexible IP network technology system according to claim 6, is characterized in that: described basic domain management entity (1) refers to have a port and mobile node (5 ) is a device that is connected to the basic network domain link, provides identity authentication for the roaming mobile node (5) and acts as an agent for the ARP network. 8. The method for realizing the self-adaptive extended domain management entity mechanism in the flexible IP network technology system according to claim 7, is characterized in that: the described extended domain management entity (3) is in the extended network of the mobile node (5) A network device that forwards registration messages and data packets for the mobile node (5) on the domain link. 9. The method for realizing the adaptive extended domain management entity mechanism in the flexible IP network technology system according to claim 8, characterized in that: the flexible IP network technology system is managed by the basic domain management entity (1) and the extended domain The entity (3) and the access management entity (2) are composed; the access management entity (2) is located between the basic domain management entity (1) and the extended domain management entity (3), and performs registration messages and data packets Forwarding, a network device with an Internet routable IP address.

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