KR20020089643A - Call setting method for internet phone system - Google Patents

Abstract

PURPOSE: A method of setting up a call in an Internet phone system is provided to share an information message to each Internet phone through a gatekeeper when an on-hook event or an off-hook event is generated in an Internet phone, thereby preventing resource consumption caused by a call setup request. CONSTITUTION: When each terminal generates an event, a gatekeeper receives a status message. The gatekeeper transmits the status message to other terminal within a network by using a broadcast IP address. Each terminal receiving the status message from the gatekeeper updates information of a self status information table by the status message. When each terminal requests a call setup, each of the terminals retrieves a status of the other terminal by the self status information table prior to the call setup request. Only when the state of the other terminal is in a standby mode, a call is set up via a call setup request procedure.

Description

Call setting method of Internet phone system {CALL SETTING METHOD FOR INTERNET PHONE SYSTEM}

The present invention relates to a call setup method of an Internet phone system. In particular, when an event such as on-hook or off-hook occurs in an Internet phone using the H.323 protocol, the information message is sent to each Internet phone through a gatekeeper. The present invention relates to a call setup method of an Internet phone system for preventing a gatekeeper from wasting resources due to a call setup request.

Recently, many Internet communication systems employing the H.323 protocol have emerged. Such communication systems generally have Internet phones, gatekeepers, gateways, etc. as basic components, as shown in FIG.

Here, the gatekeeper is a device having a call control function and has state information of all terminals (Internet phone, gateway, etc.) constituting the Internet phone system.

In order to communicate with H.323 Internet phone in the system configured as above, own information (Station ID, IP Address, Status, etc.) must be registered in advance in the gatekeeper.

Each time a call is made, the gatekeeper requests a call setup. The process is illustrated in FIG.

2, the call setup process of the Internet phone via the conventional gatekeeper is as follows.

First, the sender's Internet phone (Internet phone 1) sends an ARQ (Admission Request) message to the gatekeeper requesting the call setup approval. The gatekeeper then accepts the request by sending an ACF (Admission Confirm) message.

Then, the sender's Internet phone (Internet Phone 1) sends a setup message to the gatekeeper again, and the gatekeeper transmits the setup message sent from the sender's Internet phone to the receiver's Internet phone (Internet Phone 2).

Accordingly, the receiving Internet phone (Internet Phone 2) receiving the SETUP message sends an ARQ message to the gatekeeper requesting the call setup approval, and the receiving gatekeeper sends an ACF message to the receiving Internet phone to send the request. Allow.

Then, the receiving Internet phone transmits a CONNECT message to the gatekeeper, and the gatekeeper delivers the message to the transmitting Internet phone, from which the communication between the transmitting and receiving Internet phones is performed.

The call setup request procedure as described above is performed in the same manner as above between not only Internet phones but also Internet phones and gateways.

These procedures have a limit on the capacity that can be processed at the same time, depending on the gatekeeper's ability, and sometimes the gatekeeper cannot handle call setup requests from multiple Internet phones.

Moreover, if the receiving Internet phone receiving the call establishment request is busy, the gatekeeper processing the call connection request itself causes only the consumption of the gatekeeper's resources.

Therefore, the present invention was created to solve the above-mentioned conventional problems, and the gatekeeper transmits and shares the state information of the receiving Internet phone, which cannot accept the call, to the transmitting Internet phone, thereby making the call at the transmitting side. It is an object of the present invention to provide a call setup method of an Internet phone system in which a gatekeeper's resources are not consumed by not making a setup request, and a gatekeeper's resources are not consumed even by transmitting status information.

1 is an exemplary view shown to explain a general configuration of an internet communication system.

Figure 2 is an exemplary view shown to explain the call setup process of the Internet phone via a conventional gatekeeper.

Figure 3 is an exemplary view showing a state table of the gatekeeper according to the present invention.

4 is an exemplary diagram for explaining a method of transmitting status information of each terminal by an IP address.

FIG. 5 is an exemplary view for explaining a method of transmitting status information of each terminal by a broadcast IP address. FIG.

6 is an exemplary view showing a configuration of a status message transmitted from each terminal according to the present invention.

7 is an exemplary view illustrating a process of transmitting a status message in a gatekeeper according to the present invention.

In order to achieve the above object, the present invention provides a call setup method of an Internet phone system including a plurality of terminals and a gatekeeper, the gatekeeper comprising: a first step of receiving a status message transmitted when an event occurs in each terminal; Transmitting the status message to another terminal in a network using a broadcast IP address; Receiving each status message through the gatekeeper, updating the information in its status information table by the status message; A fourth step of retrieving the state of the counterpart terminal from its own state information table prior to the call setup request when each terminal makes a call setup request; As a result of the search, a fifth step of setting up a call through a call setup request procedure only when the other terminal is in a standby state is characterized in that it is made.

The present invention having the above-described technical configuration allows each Internet phone constituting the system to know in advance the state of other Internet phones, so that the call setup request message can be gated only when the corresponding Internet phone to be called is in a communication state. By transmitting to the, the gatekeeper's resources are not consumed by unnecessary call setup procedures.

In addition, the present invention has a feature that can minimize the processing burden of the gatekeeper according to the transmission of the status information by transmitting the status information by the broadcasting method in transmitting the status information from the gatekeeper to a plurality of terminals.

Hereinafter, an embodiment according to the present invention will be described in detail with reference to the accompanying drawings.

First, as shown in FIG. 3, the gatekeeper has a status information table that receives a message (Station ID, IP Address, Subnet Mask, etc.) from the terminal when the terminal is first registered, or is directly input by the gatekeeper operator.

Using the above data, the gatekeeper must find the broadcast IP address.

The broadcast IP address can be found by the following equation.

Last 8 bits of Broadcast IP = Index + Index x step-1

Where Index = 256- (last 8 bits of the Subnet Mask),

Step = quotient of {(last 8 bit value of IP address) ÷ Index}, that is, quotient of last 8 bits of IP address divided by index.

For example, in FIG. 3, the broadcast IP address of an Internet phone having a station ID of 1001 is

64 (Index) = 256-192,

0 (Step) = 34 ÷ 64,

63 (last 8 bits of Broadcast IP) = 64 + 64 x 0-1

Accordingly, the broadcast IP address of the terminal ID 1001 becomes 150.150.75.63, and the broadcast IP address is stored as shown in FIG.

There are two ways for the gatekeeper to transmit the status information of the terminal number 1001. First, there is a method of transmitting to the IP address of each terminal as shown in FIG. 4, and secondly, as shown in FIG. There is a method of transmitting to a broadcast IP address of the network to which the terminal belongs.

In case of transmitting status information to each terminal separately, the first method as shown in FIG. 4 is preferable. However, when several terminals belong to the same network, rather than transmitting one to an IP address of each terminal. As shown in Fig. 5, it is more efficient to transmit to the broadcast IP address of the network at once.

In other words, when the state information of the terminal number 1001 is changed by the method of FIG. Using two times to send status information minimizes the burden on the gatekeeper.

In this way, the status information of each terminal is transmitted to other terminals, and each terminal stores the received information in its own table.

Looking at the configuration of the status message, as shown in Figure 6 is composed of a message type (Message Type), terminal number (Station ID), status information (Status).

Then, the process of transmitting the status message will be described in more detail with reference to the exemplary diagram of FIG. 7.

For example, when an on-hook or off-hook event occurs in each Internet phone, a status message is sent to the gatekeeper.

Then, the gatekeeper receiving the status message sends the message to other Internet phones and gateways using the broadcast IP address.

Then, each terminal receiving the status message through the gatekeeper finds the location of the same number as the station ID (Station ID) in the status message in its status information table, the status information (Status) in the status message To update the state in the information table.

Next, using the updated information table as described above, each terminal (internet phone, gateway) first searches for the state of the counterpart terminal before requesting a call setup from the gatekeeper.

Accordingly, the call setup request can be made to the gatekeeper only when the state information of the counterpart terminal is in the idle state.

As described above, in the call setup method of the Internet phone system of the present invention, the gatekeeper transmits state information of each terminal to other terminals to share state information of each terminal, thereby preventing unnecessary call setup requests from the terminal in advance. By doing so, it is possible to efficiently use the gatekeeper's resources.

In addition, the present invention has an effect of efficiently using the resources of the server even when applied to the field of the centralized communication system such as a call server.

Claims (5)

A call setup method of an internet phone system including a plurality of terminals and a gatekeeper, the method comprising: a first step of receiving, by a gatekeeper, a status message transmitted when an event occurs in each terminal; Transmitting the status message from the gatekeeper to another terminal in the network using a broadcast IP address; Receiving each status message through the gatekeeper, updating the information in its status information table by the status message; A fourth step of retrieving the state of the counterpart terminal from its own state information table prior to the call setup request when each terminal makes a call setup request; And a fifth step of setting up a call through a call setup request procedure only when the other terminal is in a standby state as a result of the search. The method of claim 1, wherein the last 8 bits of the broadcast IP address are an index obtained by 256- (the last 8 bits of the subnet mask); The quotient of the last 8 bits of the IP address divided by the index (Step) plus the product of the index (Index × Step) minus 1 (Index + Index × Step) minus 1 (Index + Index × Step) -1) a call setup method for an internet phone system, characterized in that. The method of claim 1, wherein the terminal comprises a plurality of Internet phones and gateways. The state information table of the gatekeeper includes a station ID, an IP address, a subnet mask, and a broadcast IP address. Call setup method of an Internet phone system. The method of claim 1, wherein the status message comprises a message type, a terminal number, and status information.