KR20110006392A - Method and system for determining media path between ip phones in voip system - Google Patents

Abstract

PURPOSE: A system for determining media path between IP phones in a VoIP system is provided to construct network location information of IP phones and decide an optimal media path. CONSTITUTION: A VoIP PBX(Private Branch eXchange) receives a call connect request signal from an originating internet protocol phone(801). The VoIP PBX checks identifications of call originating IP phone and call receiving IP phone in a hierarchical position information table(802). The VoIP PBX decides whether the call originating IP phone exists in the same private network of the call receiving IP phone(803,804). If the call originating IP phone and the call receiving IP phone are in the same private network, the VoIP PBX establishes the media path between the receiving IP phone and the originating IP(805).

Description

Method and system for determining media path between IP phones in VoIP system {Method and system for determining media path between IP phones in VoIP system}

The present invention relates to a VoIP system, and more particularly, to a method of detecting information about a network environment of an IP phone in a VoIP system and optimizing a media path using the same.

Voice over Internet Protocol (VoIP) system is a communication service technology that allows voice calls to be converted into Internet protocol data packets to enable communication over a general telephone network. Recently, the VoIP system is applying NAT (Network Address Translation), an address translator for a network used to convert a private IP address into a public IP address. When NAT is set on a router, which is a device that connects to the Internet, the router only makes its public IP address known to the outside and uses only the private IP address internally, and converts them if necessary. Therefore, in order to attack the internal network, the external intruder needs to know the internal private IP address of the private network. Therefore, the router that is configured with NAT becomes impossible to attack from the outside, thereby protecting the internal network.

On the other hand, in a VoIP system, general calls between IP phones (Internet Protocol Phones) existing in the same network can be made only by configuring a media session. However, in a VoIP system with NAT, the network configuration of an IP phone is not known from the outside. Media Proxy technology provides call services for IP phones on a NAT system.

However, according to the prior art, all the media streams are connected only through the SBC / Media proxy server, which not only causes traffic overhead for the network but also wastes resources of the SBC / Media proxy server. Recently, in order to solve this problem, a method of optimizing a media stream routing path to reduce resource waste and network overhead has been actively studied.

The object of the present invention is to propose a method and apparatus for configuring network location information of an IP phone by applying an IP record route option on a VoIP system and determining an optimized media path through the information.

In the VoIP system of the present invention for solving the above problems, the method for determining a media path between IP phones includes user registration messages including path information between each IP phone and the VoIP private exchange from IP phones controlled by the VoIP private exchange. Receiving, generating a hierarchical location information table including the route information and identifiers of the respective IP phones, receiving a call connection request signal from an originating IP phone, connecting the call in the hierarchical location information table Determining whether the calling IP phone and the called IP phone exist in the same private network by checking an identifier of the calling IP phone and the called IP phone included in the request signal, and the calling IP phone and the called IP phone. Terminate the media path between the originating IP phone and the destination IP phone, if they exist in the same private network And setting the inter media path. If the source IP phone and the destination IP phone do not exist in the same private network, setting the media path between the source IP phone and the destination IP phone as a media path via a gateway via an SBC / Media proxy server. It further comprises. In addition, the user registration message is characterized in that the IP record route option is set.

In addition, the VoIP system of the present invention for solving the above problems is connected through a plurality of routers between the VoIP private exchange and the IP phone, and transmitting the user registration message including the path information between the IP phone and the VoIP private exchange And a VoIP private exchange receiving a plurality of IP phones and a user registration signal transmitted to a VoIP private exchange to generate a hierarchical location information table including the route information and identifiers of the plurality of IP phones. It is done. The VoIP private exchange further receives a call connection request signal from an originating IP phone, checks an identifier of the calling IP phone and the called IP phone included in the call connection request signal in a hierarchical location information table, When the called IP phone exists in the same private network, the media path between the calling IP phone and the called IP phone is set as an end-to-end media path. The VoIP system further includes an SBC / Media proxy server that controls the media passing between the IP phones, wherein the VoIP private exchange is configured to send the originating IP phone and the destination IP phone if they are not in the same private network. And a media path between the IP phone and the destination IP phone as a media path via the gateway via the SBC / Media proxy server. In addition, the user registration message is characterized in that the IP record route option is set.

According to the present invention, a method for determining a media path between IP phones and a system therefor according to the present invention can reduce traffic overhead on a network, maximize efficiency of SBC / Media proxy server resources, and improve IP quality of service. . In addition, according to the present invention, a method for determining a media path between IP phones and a system therefor may provide a location-based VoIP service based on hierarchically configured network location information. In addition, the present invention can be implemented through the conventional Socket API, there is an advantage that can be applied without changing the system already built.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. In this case, it should be noted that like elements are denoted by like reference numerals as much as possible. Further, the detailed description of well-known functions and constructions that may obscure the gist of the present invention will be omitted.

Also, the terms and words used in the present specification and claims should not be construed to be limited to ordinary or dictionary meanings, and the inventor is not limited to the concept of terms in order to describe his invention in the best way. It should be construed in accordance with the meaning and concept consistent with the technical idea of the present invention based on the principle that it can be properly defined.

1 is a diagram illustrating a configuration of a general VoIP system.

Referring to FIG. 1, the VoIP Private Branch Exchange (PBX) 100 resides in a public network 150 and includes IP phones A 101, B 102, and C 103. ) Is in Private Network 1 (160). Private network 1 (160) is divided into private network 2 (165) and private network 3 (170), IP phone A 101 and IP phone B 102 exist in private network 2 (165), and IP phone C 103 is present in network 3 170. The VoIP signal of IP phone A 101 is connected to the VoIP private exchange via router / NAT 104 of private network 2 165 and router / NAT 106 of authorized network 150.

FIG. 2 is an exemplary diagram showing general registration information of an IP phone in a VoIP system, and FIG. 3 is an exemplary diagram showing a general media path between IP phones existing in the same network in a VoIP system. In particular, it is assumed that IP phone A and IP phone B exist in the same local area network (LAN) environment and IP phone C exists in a different LAN environment.

2, IP phones A 201, B 202, and C 203 each transmit a user registration message to the VoIP private exchange 200, and the user registration message is " IP Header / UDP Header (Registration). Payload) ". For example, the user registration message of IP phone A 201 is "10.0.0.2/1024 (192.168.0.150/5060)", the routing address of the public network is "10.0.0.2", and the local IP address is "192.168". .0.150 ". On the other hand, it can be seen that the local IP address included in the user registration message of the IP phone C 203 is also "192.168.0.150".

Therefore, since the information included in the user registration message does not record which private network each IP phone belongs to, it is difficult to determine the private network location information between the IP phones only by using the information included in the conventional user registration message.

In order to solve this problem, conventionally, IP phone A 302 and IP phone B 303 existing in the same network as shown in FIG. 3 use media resources of the SBC / Media proxy server 301. However, even though IP phone A 302 and IP phone B 303 exist in the same private network as described above, the media stream between IP phone A 302 and IP phone B 303 is an SBC / Media proxy server. The only connection through is the traffic overhead of the network as well as waste of resources on the SBC / Media proxy server.

Hereinafter, in order to solve the above problem, a technique for generating hierarchical location information of each IP phone by using a record route option of the Internet Protocol (IP) is proposed. These record route options are easily implemented through the Socket API. In addition, although the present invention describes that the IP record route option function is applied to the user registration message, the IP record route option function can be added to the call processing message. In this case, the present invention can be applied to a wireless IP phone that is frequently mobile. Can be.

4 is a flow chart illustrating a method for an IP phone to transmit a user registration message according to an embodiment of the present invention to register its network location information with a VoIP private exchange.

Referring to FIG. 4, the IP phone declares a socket to be transmitted in step 401. In particular, in the present embodiment, it is preferable to declare a datagram type socket used when transmitting a message in which an address can be individually stored.

Subsequently, the IP phone sets an IP record route option to the socket created in step 402, and sends a user registration message to the VoIP private exchange using the socket in which the IP record route option is set in step 403. The user registration message is sent to the VoIP private exchange, recording in the header the address of the router / NAT that it passed.

5 is a flowchart illustrating a method of receiving and processing a user registration message according to an embodiment of the present invention in a VoIP private exchange.

Referring to Figure 5, the VoIP private exchange declares a socket to receive in step 501. For example, using the socket (AF_INET, SOCK_RAW, IPPRPTO_UDP) command, it is preferable to declare a socket that receives a message using the UDP protocol over the Internet. In step 502, the IP header of the message is first received.

In step 503, it is determined whether the length of the IP header is 20 bytes or less. If the IP header is longer than 20 bytes, it means that the IP header contains an IP option header. In step 504, the protocol is validated. If the length of the IP header is less than 20 bytes or does not pass the protocol validation, the received IP header is discarded. In addition, if the length of the IP header exceeds 20 bytes and passes the protocol validation, the payload of the message is received in step 505.

Subsequently, it is determined whether the IP record route option is applied to the payload of the message received in step 506, and if the message applies the IP record route option, the network location of the IP phone using the router / NAT address to which the above message was transmitted. Store information in a hierarchical location table. In this case, it is preferable to store the identifier of each IP phone together with the network location information of each IP phone. The hierarchical location information table will be described later.

6 is an exemplary diagram of network location information according to an embodiment of the present invention. In particular, the network location information of the present invention is a hierarchical location information table, and the hierarchical location information table is configured based on network information of an IP phone, and local IP / UDP information of the IP phone and public IP / UDP information translated through NAT. It includes.

Referring to FIG. 6, the VoIP private exchange generates hierarchical location information of each of the IP phones by using the record route information to which the user registration message to which the IP record route option is applied has been transmitted. In FIG. 6, two-step network location information is illustrated. Since the record route information of IP phones A and B is the same except for the last local address, IP phones A and B are located in the same network. It can be seen that it is located in another network.

In addition, the hierarchical location information table of the present invention expresses the locations of IP phones hierarchically, and IP phones A and B existing in the same network environment are A1.A2 and IP phones C are A1.B2. Here, A1, A2, and B2 are expressions indicating network locations, and may be represented by numbers or various characters. A1 refers to private network 1, A2 refers to private network 2, and B2 refers to private network 3.

7 is a diagram conceptualizing the location of each IP network through a hierarchical location information table according to an embodiment of the present invention. The IP phones present in the A1 network 701 are IP phones A 710, IP phones B 720, and IP phones C 730, of which the IP phones in A2 network 702 are IP phones A ( 710 and IP phone B 720.

8 is a flowchart illustrating a method for establishing an optimized media path by identifying location information of an incoming / outgoing IP phone when a call is connected according to an embodiment of the present invention. In particular, the media path setting method according to an embodiment of the present invention is performed using the hierarchical location information table described above.

Referring to FIG. 8, in step 801, the VoIP private exchange receives the call connection request signal and checks the identifier of the called IP phone and the originating IP phone included in the call connection request signal received in step 802. . The identifier of each IP phone is used to detect the IP phone index of FIG.

Subsequently, in step 803, the VoIP private exchange checks the location information of the two IP phones using the hierarchical location information table, and in step 804, it is determined whether the two IP phones exist in the same private network.

If present in the same network, the media path of the two IP phones is determined as an end-to-end media path in step 805. If it is not in the same network, it is determined in step 806 as the media path via the gateway through the SBC / Media proxy server. The information determined here is transmitted to the destination IP phone through the VoIP signal.

9 is a diagram illustrating an optimized media path between IP phones existing in the same network by applying a media path setting method according to an embodiment of the present invention.

9, unlike FIG. 3, the media paths of IP phone A 902 and IP phone B 903 are determined to be end-to-end media paths, thereby reducing traffic overhead and providing SBC / Media proxy server 901. It does not pass through, which can prevent resource waste.

10 is a diagram for explaining an example of using a hierarchical location information table according to an embodiment of the present invention.

Referring to FIG. 10, when a fire occurs in the private network 2 1070 and the user of the IP phone C 1003 detects the fire, the user of the IP phone C 1003 goes to the VoIP private exchange 1000. Send fire occurrence information.

The VoIP private exchange 1000 receives to IP phones A 1001 and B 1002 registered in the same private network as IP phone C 1003, that is, private network 2 1070, on the hierarchical location information table. A fire alarm can be used to transmit a fire alarm.

On the other hand, the embodiments of the present invention disclosed in the specification and drawings are merely presented specific examples to easily explain the technical contents of the present invention and help the understanding of the present invention, and are not intended to limit the scope of the present invention. It will be apparent to those skilled in the art that other modifications based on the technical idea of the present invention can be carried out in addition to the embodiments disclosed herein.

1 is a diagram illustrating a configuration of a general VoIP system.

2 is an exemplary diagram showing general registration information of an IP phone in a VoIP system.

3 is an exemplary diagram illustrating a general media path between IP phones present in the same network in a VoIP system.

4 is a flow chart illustrating a method for an IP phone to transmit a user registration message according to an embodiment of the present invention to register its network location information with a VoIP private exchange.

5 is a flowchart illustrating a method for receiving and processing a user registration message in an embodiment of the present invention in a VoIP private exchange.

6 is an exemplary diagram of network location information according to an embodiment of the present invention.

7 conceptualizes the location of each IP network through a hierarchical location information table according to an embodiment of the present invention.

8 is a flowchart illustrating a method for establishing an optimized media path by identifying location information of an incoming / outgoing IP phone when a call is connected according to an embodiment of the present invention.

9 is a diagram illustrating an optimized media path between IP phones existing in the same network by applying a media path setting method according to an embodiment of the present invention.

10 is a view for explaining an example of utilizing a hierarchical location information table according to an embodiment of the present invention.

Claims (7)

Receive user registration messages including route information between each IP phone and the VoIP private exchange from IP phones controlled by a VoIP private exchange, and include hierarchical location information table including the route information and identifiers of the respective IP phones. Generating a; Receiving a call connection request signal from an originating IP phone; Determining whether the calling IP phone and the called IP phone exist in the same private network by checking identifiers of the calling IP phone and the called IP phone included in the call connection request signal in the hierarchical location information table; And If the originating IP phone and the destination IP phone exist in the same private network, setting a media path between the originating IP phone and the destination IP phone as an end-to-end media path; To determine the media path between IP phones in the network. The method of claim 1, If the originating IP phone and the destination IP phone are not in the same private network, setting a media path between the originating IP phone and the destination IP phone as a media path via a gateway via an SBC / Media proxy server; The method of claim 1, further comprising a media path between the IP phones in the VoIP private exchange. The method of claim 1, wherein the user registration message is A method of determining a media path between IP phones in a VoIP private exchange, wherein the IP record route option is set. In a VoIP system connected between a VoIP private exchange and an IP phone through a plurality of routers,  A plurality of IP phones for transmitting a user registration message including route information between the IP phone and the VoIP private exchange to the VoIP private exchange; And a VoIP private exchange which receives the user registration signal and generates a hierarchical location information table including the route information and identifiers of each of the plurality of IP phones. 5. The VoIP private exchange of claim 4 wherein Receives a call connection request signal from an originating IP phone and checks the identifier of the originating IP phone and the destination IP phone included in the call connection request signal in a hierarchical location information table so that the originating IP phone and the destination IP phone are the same. If present in a private network, the VoIP system, characterized in that the media path between the originating IP phone and the destination IP phone is set as an end-to-end media path. The method of claim 4, wherein And an SBC / Media proxy server for controlling media passing between the IP phones. The VoIP private exchange switches the media path between the originating IP phone and the destination IP phone via a gateway through an SBC / Media proxy server when the originating IP phone and the destination IP phone are not present in the same private network. VoIP system, characterized in that the setting. The method of claim 4, wherein the user registration message is VoIP system characterized in that the IP record route option is set.

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