WO2005117346A1

WO2005117346A1 - A method of registration for the private nerwork terminal to the gatekeeper based on the h.323 protocol

Info

Publication number: WO2005117346A1
Application number: PCT/CN2004/000890
Authority: WO
Inventors: Jiazhou Li; Jia Cao; Can Shen; Jun Li
Original assignee: Zte Corporation
Priority date: 2004-05-28
Filing date: 2004-08-02
Publication date: 2005-12-08
Also published as: PT2005117346W; CN1299476C; CN1585364A

Abstract

A method of registration for the private network terminal to the gatekeeper based on the H.323 protocol includes: perform the static network address translation for the H.323 proxy server on the network address translation device, the private network terminal initiates the registration request to the H.323 proxy server; the H.323 proxy distributes the listening port to the private network terminal and modifies the registration address in the registration request into the public network address of the H.323 proxy server and above distributed listening port; H.323 proxy server registers to the gatekeeper. The present invention uses the same public network IP address and different listening port to recognize the different private network terminal so that the registration address transmitted by the private network terminal via the same H.323 proxy server is different. Thereby the gatekeeper can distinguish the different private network terminals and the problem that multiple terminals corresponds to one public network IP address is solved. Meanwhile, the present invention uses the standardH.323 protocol between the H.323 proxy server and the public network gatekeeper and thereby improves the interconnection ability between the H.323 proxy server and the different kinds of gatekeeper.

Description

Method for registering private network terminal with gatekeeper based on H. 323 protocol Technical field

The present invention relates to multimedia communication, and in particular, to a method for registering a multimedia terminal based on the H. 323 protocol.

Background technique

With the vigorous development of broadband services of IP networks in recent years, the packet-based multimedia communication system standard H. 323 protocol is widely used in video conferences and IP phones. H. 323 protocol is a packet network multimedia developed by the International Telecommunication Union ITU-T Communication standards. Because many enterprises have their own local area networks (private networks), private IP addresses are used inside the local area network. When terminals on the local area network need to access the public network, they usually undergo network address translation (Network Addres s Translatation, NAT ) The device converts the private network address to the public network address. Network address translation NAT—Generally, there are three methods: static NAT, dynamic NAT, and port NAT. The static NAT method is a one-to-one translation between a private network address and a public network address, allowing devices on the public network to access the private network. The H. 323 protocol itself does not consider the application of NAT, and its embedded address conflicts with the NAT device, which causes the problem of interworking between private and public networks.

At present, there are many methods to solve the above problems and achieve NAT device traversal. One method is to use H. 323 proxy server, specifically: H. 323 proxy server is located in the private network, and H. 323 proxy on the NAT device. The server uses static NAT to perform network address translation, so that devices on the public network can access the H.323 proxy server. Then the terminals in the private network designate the H.323 proxy server as the gatekeeper, which provides address resolution and Devices for services such as bandwidth management; terminals in the private network send registration requests to the H. 323 proxy server, and then the H. 323 proxy server acts as a terminal to register with the gatekeeper of the public network. Because the H. 323 proxy server has previously converted the IP address in the H. 323 protocol into the public network address of the static NAT of the H. 323 proxy server, the The IP address is the public network address of the H. 323 proxy server.

In the schematic diagram of the topology of a network using an H. 323 proxy server as shown in FIG. 1, terminal 1 and terminal 1 in the private network are connected to the H. 323 proxy server, and the H. 323 proxy server is connected to the NAT device. The NAT device is connected to the gatekeeper in the public network.

There are two main methods for registering with a gatekeeper using an H.323 proxy server:

1) A private protocol is used for communication between the H.323 proxy server and the public network gatekeeper. When the H.323 proxy server receives the registration message from the private network terminal, it initiates registration with the gatekeeper, and the registration message contains non-standard messages. The gatekeeper knows that the registration message is sent by the H.323 proxy server according to the non-standard message, and then the gatekeeper records the information of the terminal sent by the H.323 proxy server. If there is a call from a public network terminal, the H.323 proxy server is registered. Terminal, the gatekeeper directs the call to the H.323 proxy server. '

2) When the H. 323 proxy server receives the registration request from the private network terminal, modify the registered address in the registration message to the address of the H. 323 proxy server, and then register with the gatekeeper of the public network.

In the above first method, the registration message sent by the H. 323 terminal contains a non-standard message, which requires the non-standard message to be supported between the gatekeeper and the H. 323 proxy server. The disadvantage of this method is obvious and cannot be Solve the problem of interconnection.

In the second method, the H. 323 proxy server and the gatekeeper adopt the H. 323 standard protocol, and the registered address in the terminal registration request forwarded by the 323 proxy server adopts the public network call address of the 323 proxy server, that is, Public network IP address + port format. However, this method will cause this phenomenon, that is, all registration messages registered to the public network gatekeeper through the same H.323 proxy server correspond to the same address. This requires the gatekeeper to be able to check only the registered terminal alias (terminal name). ), Add a new registration information for the terminal alias that does not exist, so that different terminal aliases on the gatekeeper correspond to the same address. However, in practical systems, some types of gatekeepers need to check when receiving registration information. Register address, if the gatekeeper finds that the registered address is the same, it considers them to be the same terminal, and the gatekeeper will overwrite the original registration information with the newly received registration information, that is, some types of gatekeepers do not support multiple terminals corresponding to the same registration Address situation.

Summary of the invention

The technical problem to be solved by the present invention is to propose a method for registering a private network terminal with a gatekeeper based on the H.323 protocol, which overcomes the problem that when an H.323 proxy server that performs network address translation in the prior art registers with a gatekeeper, Incompatibility with different types of gatekeepers, and the case where multiple terminals do not support the same registered address.

The core idea of the present invention is: perform static network address translation on the H. 323 proxy server on the network address translation device; the private network terminal initiates a registration request to the H. 323 proxy server; the H. 323 proxy server dynamically allocates the private network terminal Listening port, and modify the registered address in the registration request to the public IP address of the H.323 proxy server and the listening port allocated above; the H.323 proxy server registers with the public network gatekeeper.

The method for registering a private network terminal based on the H. 323 protocol with a gatekeeper according to the present invention specifically includes: establishing a listening port pool according to the number of private network terminals proxied by the H. 323 proxy server; The 323 proxy server performs static network address translation and opens the port of the listening port pool. Set the listening port pool on the H. 323 proxy server.

The private network terminal designates the public network gatekeeper as the proxy server, and sends a registration request to the H.323 proxy server;

H. The 323 proxy server determines whether the private network terminal is registered for the first time after receiving the registration request from the private network terminal; if so, it selects a port in the listening port pool that is not occupied by another terminal, and Listen on the port; if not, use the listening port assigned to the private network terminal;

The H. 323 proxy server modifies the registered address in the registration request message to the public network address of the H. 323 proxy server after static network address translation and the H. 323 proxy server assigns the private network terminal Listening port, sending a registration request message to the gatekeeper;

The gatekeeper authenticates the received registration request; if the authentication is passed, the registration information of the private network terminal is recorded; the gatekeeper sends a confirmation message to the H.323 proxy server, and the H.323 proxy server records the private network terminal after receiving it And send a confirmation message to the private network terminal, and the registration ends;

If the authentication fails, the gatekeeper sends a rejection message to the H.323 proxy server. After receiving, the H.323 proxy server releases the listening port of the private network terminal and sends a rejection message to the private network terminal. The registration ends.

In the above method, the number of listening port pool ports is equal to the number of private network terminals proxied by the H.323 proxy server.

In the above method, the registered address in the registration request sent by the private network terminal to the H.323 proxy server is the private network address of the private network terminal and a listening port on the private network terminal.

In the above method, if the gatekeeper authenticates the registration request sent by the H.323 proxy server, check whether the private network terminal is registered for the first time; if so, add the registration information of the private network terminal; if the If the private network terminal has been registered, the registration information of the private network terminal is updated.

In the present invention, the above method further includes the step of actively canceling the registration of the private network terminal, specifically: the private network terminal sends a message to cancel the registration to the H.323 proxy server; the H. 323 proxy server releases it as the private network terminal after receiving it The assigned listening port then sends a deregistration message to the gatekeeper; after receiving the deregistration message, the gatekeeper sends a deregistration confirmation message to the H.323 proxy server; the H.323 proxy server will receive a deregistration confirmation message Forward to the private network terminal, and cancel the registration.

In the present invention, the above method further includes the step of the gatekeeper canceling the registration of the private network terminal, which is specifically: the gatekeeper sends a message to cancel the registration of the private network terminal to the H. 323 proxy server; The listening port allocated for the deregistered private network terminal, and then sends a deregistration message to the private network terminal. After receiving the deregistration message, the private network terminal sends a request to the H.323 proxy server. The registration confirmation message is cancelled. The H. 323 proxy server forwards the registration cancellation confirmation message to the gatekeeper, and the gatekeeper cancels the registration of the private network terminal.

The method of the present invention establishes a listening port pool, and uses the same public network IP address and different listening ports to identify different private network terminals, so that different private network terminals pass through the same H.323 proxy server. The registered addresses are different, so that the gatekeeper can distinguish different private network terminals, and solves the problem that multiple terminals correspond to the same public network IP address. At the same time, the invention adopts a standard between the H.323 proxy server and the public network gatekeeper. The H. 323 protocol improves the interoperability between H. 323 proxy servers and different types of gatekeepers.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 is a schematic diagram of the topology of a network using an H.323 proxy server;

2 is a flowchart of a registration method of the present invention;

3 is a flowchart of a private network terminal actively canceling registration in the present invention;

FIG. 4 is a flowchart of the gatekeeper canceling the registration of the private network terminal in the present invention.

detailed description

The present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

FIG. 1 is a schematic diagram of a network using an H. 323 proxy server, which has been described in the background art. The method of the present invention is also based on the network shown in FIG. 1, in which messages between the H.323 proxy server and the public network gatekeeper use the H.323 standard protocol for interaction.

The core idea of the present invention lies in: In the H.323 standard protocol, the registered address of a private network terminal is expressed by using the private network IP address of the terminal plus the listening port of the terminal. When the 323 proxy server is registered, it dynamically allocates listening ports to different private network terminals, and uses the same public IP address of the H.323 proxy server and different listening ports to identify different private network terminals, so that different private network terminals The registered address sent by the network terminal through the same H. 323 proxy server is different , Thereby enhancing the interworking performance with different gatekeepers.

The main process of the method of the present invention is as follows: First, the H.323 proxy server establishes a listening port pool. After receiving the registration request of the private network terminal, the H.323 proxy server removes a listening port from the listening port pool, and The registered address of the network terminal registration request is modified to the public IP address of the H, 323 proxy server and the listening port assigned to the terminal, and then registered with the gatekeeper. If the registration fails, the H. 323 proxy server releases the private network. The listening port of the terminal for use by other terminals when registering.

The specific steps of the method of the present invention are shown in FIG. 2. First, the H.323 proxy server defines a listening port pool, that is, a segment of a port address according to the number of private network terminals that need to be proxyed. In one embodiment of the present invention, the number of ports listening on the port pool is the same as that of the H.323 proxy server. The number of proxy private network terminals is equal. Next, perform static NAT on the H.323 proxy server on the network address translation NAT device to obtain the public IP address of the H, 323 proxy server, and then open the listening port pool to allow terminals outside the NAT device to access the Η. 323 proxy The port on which the server listens; set the listening port pool on the 323 proxy server, and then start the 323 proxy server. The private network terminal designates the gatekeeper as a proxy server, and sends a registration request to the 323 proxy month server, where the registered address is the private network address of the private network terminal and a listening port on the private network terminal. Η. After receiving the registration request from the private network terminal, the 323 proxy server determines whether the private network terminal is registered for the first time. The specific judgment method is to check whether the record of the private network terminal exists on the proxy server. If there is no record of the private network terminal, it indicates that the private network terminal is not registered for the first time, and the listening port allocated for the private network terminal is used for listening; if it exists, it indicates that the terminal is the first registration, Then, select a port in the listening port pool that is not occupied by other private network terminals, and listen on this port. Then, the 323 proxy server modifies the received registration request message, and changes the registered address to Η. The public network address of the 323 proxy server and Η. The listening port assigned by the 323 proxy server to the private network terminal, and then sends it to the network. Shou sends a registration message. The gatekeeper performs authentication after receiving the registration request message from the 323 proxy server. If the authentication succeeds and the private network terminal is For the first registration, the registration information of the private network terminal is added; if the authentication is passed and the private network terminal has been registered, the registration information of the private network terminal is updated. Finally, the gatekeeper sends a registration confirmation message to the H. 323 proxy server. After receiving, the H. 323 proxy server records the registration information of the private network terminal, and sends a confirmation message to the private network terminal, and the registration ends. If the gatekeeper fails the authentication of the registration request message, the gatekeeper sends a registration rejection message to the H.323 proxy server. After receiving the H.323 proxy server, it releases the listening port allocated for the private network terminal, and sends the The private network terminal sends a rejection message, and the registration ends.

As shown in FIG. 3, the step of actively canceling the registration of the private network terminal includes: The private network terminal sends a deregistration message to the H.323 proxy server; the H. 323 proxy server releases the listening port allocated for the private network terminal after receiving the message. , And then send a deregistration message to the gatekeeper; after receiving the deregistration message, the gatekeeper sends a deregistration confirmation message to the H.323 proxy server; the H.323 proxy server forwards the received deregistration confirmation message to the private network terminal At this point, the deregistration process ends.

The process of the gatekeeper canceling the registration of the private network terminal shown in FIG. 4 includes: the gatekeeper sends a message to the H.323 proxy server to cancel the registration of the private network terminal; the H. 323 proxy server releases it as the cancelled registration private server after receiving it. The listening port allocated by the network terminal, and then sends a deregistration message to the private network terminal; after receiving the deregistration message from the H.323 proxy server, the private network terminal sends a deregistration confirmation message to the H.323 proxy server; H 323 The proxy server forwards the message to the gatekeeper after receiving the deregistration confirmation message. At this point, the process of the gatekeeper canceling the registration of the private network terminal ends.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not limiting. Although the present invention is described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technology of the present invention can be Modifications or equivalent replacements of the solutions without departing from the spirit and scope of the technical solutions of the present invention should be covered by the claims of the present invention.

Claims

Claim

1. A method for registering a private network terminal with a gatekeeper based on the H. 323 protocol, comprising: performing static network address translation on a H. 323 proxy server on a network address translation device; the private network terminal reports to H. The 323 proxy server initiates a registration request; the H. 323 proxy server dynamically allocates a listening port to the private network terminal, and modifies the registered address in the registration request to the public network IP address of the H. 323 proxy server and the allocated listening port. ; H. 323 proxy server registers with the public network gatekeeper.

2. The method for registering a private network terminal with a gatekeeper based on the H. 323 protocol according to claim 1, further comprising the following steps:

Establish a listening port pool based on the number of private network terminals proxied by the H. 323 proxy server; perform static network address translation on the H. 323 proxy server on the network address translation device, and open the ports listening on the port pool; proxy on the H. 323 proxy Setting the listening port pool on the server;

The H. 323 proxy server modifies the registered address in the registration request message to the public network address of the H. 323 proxy server after static network address translation and the listening port allocated by the H. 323 proxy server to the private network terminal to the gatekeeper Send a registration request message;

The gatekeeper authenticates the received registration request; if the authentication is successful, the registration information of the private network terminal is recorded; the gatekeeper sends a confirmation message to the H.323 proxy server, and the H.323 proxy server records the private network terminal after receiving it And send a confirmation message to the private network terminal, and the registration ends;

If the authentication fails, the gatekeeper sends a rejection message to the H. 323 proxy server. After receiving the H. 323 proxy server, #puts the listening port of the private network terminal and sends a rejection message to the private network terminal. Booklet is over.

3. The method for registering a private network terminal based on the H.323 protocol with a gatekeeper according to claim 2, wherein the method for determining whether the private network terminal is registered for the first time is specifically: checking the proxy server Whether there is a record of the private network terminal on the Internet, if there is no record of the private network terminal, it indicates that the private network terminal is not registered for the first time; if it exists, it indicates that the private network terminal is the first registration.

4. The method for registering a private network terminal based on the H.323 protocol with a gatekeeper according to claim 1 or 2, characterized in that the number of ports in the listening port pool and the private network proxied by the H.323 proxy server The number of terminals is equal.

5. The method for registering a private network terminal based on the H. 323 protocol with a gatekeeper according to claim 1 or 1, wherein the registered address in the registration request sent by the private network terminal to the H. 323 proxy server Is the private network address of the private network terminal and a listening port on the private network terminal.

6. The method for registering a private network terminal based on the H.323 protocol with a gatekeeper according to claim 1 or 2, wherein after the gatekeeper passes the authentication of the registration request sent by the H.323 proxy server, Recording the registration information of the private network terminal specifically includes: if the gatekeeper authenticates the registration request sent by the H.323 proxy server, check whether the private network terminal is registered for the first time; if so, add the private network terminal Registration information of the network terminal; if the private network terminal has been registered, update the registration information of the private network terminal.

7. The method for registering a private network terminal based on the H.323 protocol with a gatekeeper according to claim 1 or 2, characterized in that the method further comprises the step of actively canceling the registration of the private network terminal, specifically: a private network The terminal sends a deregistration message to the H. 323 proxy server. After receiving the H. 323 proxy server, it releases the listening port allocated for the private network terminal, and then sends a deregistration message to the gatekeeper. The gatekeeper receives the deregistration message. After that, the H. 323 proxy server sends a deregistration confirmation message; the H. 323 proxy server forwards the received deregistration confirmation message to the private network terminal.

8. The method for registering a private network terminal with a gatekeeper based on the H.323 protocol according to claim 1 or 2, further comprising the step of the gatekeeper canceling the registration of the private network terminal, specifically: the gatekeeper Send a message to the H.323 proxy server to cancel the registration of the private network terminal; after receiving the message, the H. 323 proxy server releases the listening port allocated for the private network terminal to be deregistered, and then sends a message to the private network terminal to cancel the registration; After receiving the message of deregistration, the private network terminal sends a confirmation message of deregistration to the H. 323 proxy server; the H. 323 proxy server forwards the deregistration confirmation message to the gatekeeper.