KR20100090338A - Udp hole punching method using sip, terminal management system and management method using the udp hole punching method - Google Patents

Abstract

PURPOSE: A UDP hole punching method using SIP and a system and a method for managing terminal using the same are provided to simply form a UDP hole by using a specific SIP message for generating an internet call and controlling a session, thereby performing interactive remote terminal management in real time. CONSTITUTION: A call generator(310) generates an SIP(Session Initiation Protocol) message. The call generator transmits a call generation message to an internet phone terminal(410). If a SIP INVITE message of the call generator is received, a SBC(Session Border Controller) device(500) changes a private IP in a SDP(Session Description Protocol) to a public IP. A terminal management server(110) generates various management information through SNMP(Simple Network Management Protocol) or HTTP message exchange with the internet phone terminal.

Description

GPD hole punching method using SIP, terminal management system and terminal management method using same {UDP HOLE PUNCHING METHOD USING SIP, TERMINAL MANAGEMENT SYSTEM AND MANAGEMENT METHOD USING THE UDP HOLE PUNCHING METHOD}

The present invention relates to a UDP hole punching method capable of remotely managing a terminal in a NAT environment using Session Initiation Protocol (SIP), a terminal management method using the same, and a terminal management system.

NAT is a technique used to solve the IP address shortage problem. However, by separating the user environment from the inside and the outside based on NAT, the role of a firewall that blocks sessions from the outside becomes incidental. When using an IP router with a built-in NAT function, a terminal under the NAT is assigned with its own private IP assigned by the IP router, and there is a problem that an Internet phone service provider cannot directly control a user terminal. Due to this problem, the Internet phone service provider needs to monitor the service failure of the service terminal provided to the customer, and when a problem occurs in the service terminal, there is a limit in providing A / S through remote control. Service failures include software or hardware failures. There are various conventional methods to overcome this problem, but in order to use these methods, an Internet phone service provider must upgrade a user-owned NAT device that cannot directly control remotely or provide a function of a specific standard. In addition, the existing methods for managing a service terminal in a NAT environment may not properly manage a NAT operating in a specific manner and may cause unnecessary network traffic.

It is an object of the present invention to provide a method for realizing two-way remote management of an Internet telephone terminal without upgrading NAT apparatus and terminal equipment, using a specific standard, or inducing unnecessary traffic generation.

An object of the present invention is to provide a UDP hole punching method using a SIP capable of performing terminal management using specific message information of SIP, a terminal management method using the same, and a terminal management system.

In a NAT (user datagram protocol) hole punching method using a SIP between a terminal and a terminal management server in a NAT environment according to an aspect of the present invention, a call generation message for generating a call is generated and transmitted to the terminal from the terminal. A trap message corresponding to the call generation message is delivered to the terminal management server, and a request message is transmitted from the terminal management server to the terminal in response to the trap message to generate a UDP hole. . The transmitting of the trap message may include: transmitting a trap message by fixing each of a source port of the terminal and a destination port of the terminal, and converting the source port of the fixed terminal into a port assigned to the NAT environment so that the terminal And forwarded to the management server. The generating of the UDP hole may include: fixing a destination port of the fixed terminal as a source port of the terminal management server, setting a port assigned in the NAT environment as a destination port, and transmitting a request message; Converting a destination port of the message into a source port of the fixed terminal, and transmitting the request message to the terminal.

A terminal management system for managing a terminal in a NAT environment according to another aspect of the present invention generates a SIP message and a call call generator for transmitting a call generation message to a terminal to be managed, and by exchanging a message of the predetermined type with the terminal And a terminal management server which collects event information generated in the terminal and executes setting and control necessary for the terminal. When the trap message is transmitted to the terminal management server in response to the call generation message, the terminal management server includes: By transmitting a request message to the terminal, a user datagram protocol (UDP) hole is formed in the terminal and the terminal management server. The trap message is transmitted to the terminal management server by fixing each of the source port of the terminal and the destination port of the terminal, the source port of the fixed terminal is converted into a port assigned to the NAT environment and transmitted to the terminal management server. do. The terminal management server fixes the destination port of the fixed terminal as the source port of the terminal management server, and sets the port assigned in the NAT environment as the destination port to send the request message. The destination port of the request message is converted to the source port of the fixed terminal, and the request message is delivered to the terminal.

According to another aspect of the present invention, there is provided a management method for managing a terminal in a NAT environment, wherein a call generation message for generating a call is generated and delivered to the terminal. A trap message corresponding to the call generation message is received from the terminal. In the step of being delivered to the terminal management server, a request message is transmitted from the terminal management server to the terminal in response to the trap message to generate a UDP hole and to collect event information generated in the terminal using the formed UDP hole And performing setting and control necessary for the terminal. The transmitting of the trap message may include: transmitting a trap message by fixing each of a source port of the terminal and a destination port of the terminal, and converting the source port of the fixed terminal into a port assigned to the NAT environment so that the terminal And forwarded to the management server. The generating of the UDP hole may include: fixing a destination port of the fixed terminal as a source port of the terminal management server, setting a port assigned in the NAT environment as a destination port, and transmitting a request message; Converting a destination port of the message into a source port of the fixed terminal, and transmitting the request message to the terminal.

According to the Internet phone terminal management method according to the present invention, by using a specific SIP message used for Internet phone call generation and session control, a simple UDP (User Datagram Protocol) hole can be formed to perform bidirectional terminal remote management in real time. .

In addition, through management information collected from the terminal, it is possible to efficiently handle tasks such as after-sales monitoring for service failures and remote control in case of problems, including software or hardware failures of the terminal.

In addition, it is possible to improve the quality of customer service by reflecting the remote upgrade of the terminal and the service policy and subscriber requirements of the Internet phone service provider in real time.

According to the present invention, there is provided a UDP hole punching method, a terminal management method, and a management system using the same.

In addition to the general Internet service, the present invention provides a UDP hole punching method using SIP, a terminal management method using the same, and a management system that can manage terminals located under the Internet router even in an environment where a user configures NAT using the Internet router.

The present invention also provides a UDP hole punching method, which is managed by an internet telephony service provider using a technology such as Simple Network Management Protocol (SNMP), a terminal management method and a management system using the same.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention. In the drawings, parts irrelevant to the description are omitted in order to clearly describe the present invention. Like reference numerals designate like parts throughout the specification.

Hereinafter, with reference to the accompanying drawings will be described in detail with respect to the Internet phone terminal management method and terminal management system using a SIP message in a NAT environment according to the present invention.

In general, the terminal management system uses a method such as Simple Network Management Protocol (SNMP) or Hyper Text Transfer Protocol (HTTP) to remotely acquire status information about the terminal device or directly reflect necessary management information to the terminal. In case of SNMP, terminal management is performed by using Trap message or using methods such as SET and GET.In case of HTTP, using methods such as SOAP (Simple Object Access Protocol) and XML-RPC (XML-RPC) Perform terminal management.

For example, a terminal management system using SNMP for terminal management collects event information generated in a terminal device through SNMP traps, and executes settings and control necessary for the terminal device using methods such as SNMP Get and Set.

In a NAT environment, the terminal management system cannot pass NAT through commands such as SNMP Get and Set for terminal management, thereby making it impossible to provide a normal management service. In particular, it is impossible to obtain the status information of the terminal in real time except through a method of periodically uploading its information to the terminal management system in the form of an SNMP trap that the terminal periodically uploads to the terminal management server. In addition, important functions for reflecting the service policy of the Internet telephone service provider in the terminal or for changing the configuration for immediate response in case of terminal failure cannot be performed. Event information generated from the terminal can be collected normally through the SNMP trap message to the terminal management system.However, commands such as SNMP Get and Set for the actual control and configuration from the terminal management system to the terminal cannot pass through NAT. impossible. That is, a terminal management system in a NAT environment can only unidirectionally manage depending on information provided by a terminal.

In an embodiment of the present invention, a UDP hole punching method using SIP that can provide necessary information, setting, and control between a terminal and a terminal management server using a user datagram protocol (UDP) hole, and a terminal management system using the same. And a management method. UDP holes are formed for peer-to-peer communication between two peers blocked by different NATs, and forming a UDP hole is called UDP hole punching. UDP hole punching uses a method of initializing a hole keeping timer maintained by NAT by periodically sending a "keep alive message" from a client inside the private network to maintain a UDP session. At this time, UDP hole holding time varies according to the type of router, so "keep alive message" should be transmitted at appropriate intervals.

Hereinafter, the present invention will be described in detail with reference to FIGS. 1 to 6.

1 is a diagram showing the configuration of an Internet telephony service system using SIP.

As shown in FIG. 1, the Internet telephony service system 1 includes a SIP proxy server 100, a location server 200, and a session border controller (SBC) device 500_1 and 500_2. The SIP proxy server 100 processes the SIP message generated from the UAC sender 300 or the UAS receiver 400. The location server 200 registers a user through a register message and stores a registered user's access address. Each of the UAC (User Agent Client) 300 generating an Internet telephone call and requesting a call and the UAS (User Agent Server) 400 receiving and responding to the requested call are connected to the SBC devices 500_1 and 500_2. The SBC apparatus 500_1 periodically exchanges a register message with the UAC 300 so that the call can be transferred to the UAC 300 under the registered NAT. The SBC apparatus 500_2 periodically exchanges a register message with the UAS 400 so that the call can be transferred to the UAS 400 under the registered NAT.

2 is a view showing a basic configuration for explaining the Internet phone terminal management in a NAT environment according to an embodiment of the present invention. The terminal management system (2) according to the present invention is an SBC that provides a traversal function of a call generator (310) capable of generating an Internet telephone call using SIP and a NAT device 600 of an internet telephone call. (Session Border Controller) 500, a terminal information collection server (hereinafter, terminal management server) using a remote management technology such as SNMP or HTTP (110), and the Internet phone terminal 410. Here, the Internet phone terminal 410 is a telephone or an MTA (Media Termination Adapter) including an Internet phone module to be used as a wire, a soft phone used as a software in a PC and a Wi-Fi used in a wireless LAN network environment used wirelessly. -Includes all types of terminals used in the form of Internet telephony, such as Fi cordless telephones and digital cordless telephones.

The call call generator 310 generates a SIP message and delivers a call generation message to an Internet phone terminal to be managed.

When the SBC device 500 receives the SIP INVITE message of the call call generator, the SBC device 500 converts the private IP inside the SDP into its own public IP and delivers it to the Internet phone terminal 410.

The terminal management server 110 serves to generate various management information by exchanging SNMP or HTTP messages with the Internet phone terminal 410. When the terminal management server 110 uses the SNMP message, the terminal management server 110 collects event information generated in the Internet telephone terminal 410 using the SNMP trap message, and the Internet telephone terminal through the SNMP Get and Set commands. Perform settings and control necessary for 410. On the other hand, when the terminal management server 110 uses an HTTP message, the terminal management server 110 collects the Internet phone terminal 410 information through a specific function definition using SOAP or XML-RPC, and the Internet phone terminal Perform settings and control necessary for 410.

Hereinafter, an embodiment of the present invention for terminal management using SNMP will be described. First, the packet format of SNMP will be described with reference to FIG. 3.

3 illustrates the format of a Simple Network Management Protocol (SNMP) packet for traversing NAT. SNMP packets include IP headers, UDP headers, and SNMP messages. The IP header includes a source IP address and a destination IP address, and the UDP header includes a source port and a destination port. SNMP messages include Agent IP addresses and data. In addition to the source IP address on the IP header of the SNMP trap message, the SNMP packet format includes an Agent IP address, which is the IP of an actual Internet telephone terminal, in the SNMP message. In this case, the Agent IP address and the source IP address are the same in the environment using the public IP, but when using the private IP through NAT, the SNMP Agent IP address is assigned a private IP address, and the source IP address is the public IP received by the NAT device. The address is assigned.

4 is a diagram illustrating a network address translation operation of a NAT device. The SNMP packet 111 is an SNMP packet transmitted from the Internet telephone terminal 110, and the SNMP packet 112 shows a packet converted by the SNMP packet 111 through the NAT device 600.

The NAT device 600 is assigned an external public IP address (211.xx x) from an external Dynamic Host Configuration Protocol (DHCP) server (Dynamic IP Assignment) or a router (Static IP Assignment), and internal private IP to NAT subordinate devices. (192.xx x), and has mapping table 601 of external public IP address / UDP (User Datagram Protocol) port and internal private IP address / UDP port. The mapping table 601 is internally maintained for a certain time for reception.

Hereinafter, a UDP hole generation according to an embodiment of the present invention will be described with reference to FIG. 5. 5 is a diagram illustrating UDP hole generation.

As shown in FIG. 5, the call call generator 310 corresponding to the UAC 300 generates and sends a SIP INVITE message to the SBC 500 according to the call call generation procedure, and the SBC 500 registers the registered NAT device. In step 600, the INVITE message is directly transmitted to the Internet telephone terminal 410. Here, the same procedure may be followed by using a message for SMS transmission called "MESSAGE" instead of an INVITE message for call generation of SIP.

In general, the SIP message includes a Session Description Protocol (SDP) indicating details, and in this case, the SDP information in the INVITE message includes information for transmitting an SNMP trap to the terminal management server 110 by the Internet telephone terminal 410. Include.

The SDP information included in the SIP message body is as follows. The following detailed SDP information is an example.

[SDP Information]

m = audio 41352 RTP / AVP 0 8

a = snmp-trap: tpye1 Terminal Management Server IP Address

Here, m includes information on the media type, port number, transmission protocol, and payload type (codec), and a is information indicating the characteristics of the media, and the Internet telephone terminal 410 reads the information and gives an SNMP trap. It contains a proposal to form a UDP hole by uploading to the terminal management server IP address. In a, type1 is an additional field to indicate whether to raise the SNMP trap periodically or once.

Internet phone terminal 410, which is a management target terminal, receives the above SDP information from the call call generator and fills the following SDP information with the call call generator 310, using a response code "406 (Not Acceptable)". Responds and ends the call. Since the call generated from the call call generator 310 is not an actual Internet phone call, the call is answered with the response code "406 (Not Acceptable)".

[SDP Information]

m = audio 4000 RTP / AVP 0

a = snmp-trap: type1

If "MESSAGE" is used without using the INVITE message, the Internet phone terminal 410, which is a management target terminal, does not need to respond to the call call generator 310 by using a separate response code.

When the INVITE is introduced, the Internet phone terminal 410 may receive a call, for example, a ring generation, a call wait tone, a call number indication (CID), and the like, for a call whose SDP attribute a starts with snmp-trap. Do not perform the act. In addition, no special measures are required when introducing "MESSAGE".

In addition, after receiving the INVITE message, the Internet phone terminal 410 responds with a response code 406, terminates the call immediately, processes the SNMP trap information, and sends an SNMP trap message to the terminal management server 110. Likewise, when receiving a message, there is no need to generate a separate response code. The terminal management server 110 transmits an SNMP request message to the Internet telephone terminal 410. Then, a UDP hole is formed between the Internet phone terminal 410 and the terminal management server 110. Then, the Internet phone terminal 110 periodically sends a specific trap to the terminal management server 110 at intervals below the period during which the mapping table 601 of the NAT device 600 is maintained using the UDP hole. If necessary, the above-described UDP hole generation process using SIP may be repeatedly performed as necessary. Then, the terminal management server 110 may reach the Internet phone terminal 110 using the mapping table information 601. As described above, the NAT device 600 may generate a UDP hole by using the characteristic of generating and maintaining the mapping table 601, thereby solving a NAT traversal problem.

At this time, for the SNMP trap call received during the general Internet phone call of the Internet phone terminal 410, the response code 406 is transmitted and the existing call is maintained normally. In addition, after the SNMP trap call is terminated, the SNMP trap message as described below is normally sent to create a UDP hole.

6 is a diagram illustrating a method of generating a UDP hole by transmitting an SNMP trap message after an SNMP trap call ends.

As shown in FIG. 6, the SNMP trap message transmitted from the Internet telephone terminal 410 to the terminal management server 110 is a source IP address (actually, a terminal private IP address) and a port number as UDP described in RFC 1157. It is set to 161. The source IP address and the port number are secured to the NAT device 600 as mapping information with the terminal management server. In addition, the Internet phone terminal 410 transmits the IP address of the terminal management server 110 specified in the a attribute value of the SDP information of the SNMP trap message as the destination IP address and the destination port number as UDP 162. do. The Internet phone terminal 410 transmits an SNMP trap message to the terminal management server 110 by fixing a source port and a destination port to allow SNMP Get / Set from the terminal management server 110. In an embodiment of the present invention, 161 and 162 are respectively fixed as a source port and a destination port. Source port and destination port are included in attribute information of SIP SDP. That is, a terminal such as the Internet phone terminal 410 obtains source and destination fixed ports from attribute information of the SDP, and transmits an SNMP trap message to the terminal management server 110. The terminal management server 110 sends the SNMP Get / Set to the destination fixed port in the SNMP trap message and passes through the NAT device 600.

In addition, a unique attribute value is given to each Internet telephony terminal for convenience of terminal management, and the Internet telephony terminal includes its unique attribute value in the data field on the SNMP trap message and transmits it. In this case, the unique attribute value may be information such as a hardware MAC (Media Access Control) address of the Internet telephone terminal or a telephone number of the Internet telephone terminal. In addition, a type field may be added to the SNMP trap message to identify whether the information is periodically uploaded by the terminal management server or required information in real time.

The NAT device 600 converts the source IP (192.xxx) of the IP header to the shared IP (228.xxx) in the SNMP trap packet, and assigns the source port 161 of the UDP header header to the NAT device 600. Change to port 13345 to transmit the SNMP trap to the terminal management server (110). In the NAT device 600, UDP holes of (228.x.x.x: 13345 and 192.x.x.x: 161) are formed.

The terminal management server 110 can know the IP and port of the NAT device 600, that is, the router, to be used for the private IP and UDP hole punching of the Internet telephone terminal 410 through the SNMP trap message. The terminal management server 110 requests the SNMP Get / Set to the public IP address of the NAT device to execute the necessary settings and control for the Internet phone terminal 410 using such information. In this case, even in the case of a specific NAT, even if the internal IP address and port information going out from the inside of the device are the same, if the destination address or port is different, the port number mapped from the NAT is also different. For this reason, the terminal management server 110 should request SNMP Get and Set to the NAT device 600 using the UDP port 162 specified by the Internet phone terminal 410 uploading an SNMP trap message.

When the NAT device 600 receives the SNMP Get / Set request, the NAT device 600 converts the private IP of the Internet phone terminal 410 and transmits the SNMP Get / Set request to the Internet phone terminal 410.

The internet phone terminal 410 transmits an SNMP response to the received SNMP Get / Set request to the terminal management server 110 using a UDP hole.

When the terminal management is performed using HTTP SOAP or SML-RPC in addition to the terminal management using SNMP described above, all processes and methods are the same. In particular, as related commands were executed by specifying UDP port 161 and 162 specified in RFC 1157 in SNMP, even when using SOAP or XML-RPC, a specific port is defined by fixing the port even though it is not a number specified in the protocol. Command execution should be done using the specified port.

The drawings and detailed description of the invention are merely exemplary of the invention, which are used for the purpose of illustrating the invention only and are not intended to limit the scope of the invention as defined in the meaning or claims. Therefore, those skilled in the art will understand that various modifications and equivalent other embodiments are possible from this. Therefore, the true technical protection scope of the present invention will be defined by the technical spirit of the appended claims.

1 is a diagram showing the configuration of an Internet telephony service system using SIP.

2 is a view showing a basic configuration for explaining the Internet phone terminal management in a NAT environment according to an embodiment of the present invention.

3 illustrates the format of a Simple Network Management Protocol (SNMP) packet for traversing NAT.

4 is a diagram illustrating a network address translation operation of a NAT device.

5 is a diagram illustrating UDP hole generation.

6 is a diagram illustrating a method of sending an UDP trap message after an SNMP trap call is terminated to format a UDP hole.

Claims (10)

In a NAT (user datagram protocol) hole punching method using a SIP between a terminal and a terminal management server in a NAT environment, Generating and transmitting a call generation message for call generation to the terminal; Transmitting a trap message corresponding to the call generation message from the terminal to the terminal management server; And And a UDP hole is generated by transmitting a request message from the terminal management server to the terminal in response to the trap message. The method of claim 1, The step of transmitting the trap message, Transmitting a trap message by fixing a source port of the terminal and a destination port of the terminal; And And a source port of the fixed terminal is converted into a port assigned to the NAT environment and transferred to the terminal management server. The method of claim 2, The step of generating the UDP hole, Fixing a destination port of the fixed terminal as a source port of the terminal management server, and setting a port assigned as the destination port in the NAT environment to transmit a request message; And And converting a destination port of the request message into a source port of the fixed terminal, and transmitting the request message to the terminal. In a terminal management system for managing a terminal in a NAT environment, A call call generator for generating a SIP message and delivering a call generation message to a terminal to be managed; and And a terminal management server which exchanges a message of a predetermined format with the terminal, collects event information generated in the terminal, and executes setting and control necessary for the terminal. When a trap message is transmitted to the terminal management server in response to the call generation message, the terminal management server transmits a request message to the terminal to form a user datagram protocol (UDP) hole in the terminal and the terminal management server. Management system. The method of claim 4, wherein The trap message is transmitted to the terminal management server by fixing each of the source port of the terminal and the destination port of the terminal, the source port of the fixed terminal is converted into a port assigned to the NAT environment and transmitted to the terminal management server. Terminal management system. The method of claim 5, The terminal management server, A terminal management system for transmitting the request message by fixing the destination port of the fixed terminal to the source port of the terminal management server, the port assigned in the NAT environment as a destination port. The method of claim 6, And a destination port of the request message is converted into a source port of the fixed terminal, so that the request message is delivered to the terminal. In a management method for managing a terminal in a NAT environment, Generating a call generation message for call generation and transmitting the call generation message to the mobile station; Transmitting a trap message corresponding to the call generation message from the terminal to the terminal management server; Generating a UDP hole by transmitting a request message from the terminal management server to the terminal in response to the trap message; and And collecting event information generated in the terminal by using the formed UDP hole, and executing setting and control necessary for the terminal. The method of claim 8, The step of transmitting the trap message, Transmitting a trap message by fixing each of the source port and the destination port of the terminal; And converting the source port of the fixed terminal into a port assigned to the NAT environment and transmitting the converted port to the terminal management server. 10. The method of claim 9, The step of generating the UDP hole, Fixing a destination port of the fixed terminal as a source port of the terminal management server, setting a port assigned in the NAT environment as a destination port, and transmitting a request message; And converting a destination port of the request message into a source port of the fixed terminal and transmitting the request message to the terminal.

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