KR100392226B1 - Mobile internet protocol application method for mobile internet phone service - Google Patents

Abstract

The present invention relates to an integrated structure of Mobile Internet Protocol (Mobile IP) and H.323 for providing an Internet telephony service in a mobile environment. The present invention relates to IP by converging mobility technology of Mobile Internet Protocol while maintaining the system structure of H.323. It is designed to enable voice transmission not only to fixed hosts but also to mobile hosts on the underlying network, and to extend IP standards proposed by the current IETF mobile Internet protocol to provide IP mobility in the intra domain. It is an excellent invention that can maintain compatibility with existing H.323 systems by using multiple connection maintenance methods at the gateway to provide IP mobility without the need to change the existing H.323 standard and define additional entities.

Description

Mobile Internet protocol application method for mobile internet phone service

The present invention relates to a method of applying a mobile internet protocol for a mobile internet telephony service, and more particularly, to a mobile internet protocol for providing an internet telephony service in a mobile environment and an international telecommunications union-telecommunication standard series H.323 (ITU). -T H.323, hereinafter referred to as H.323), that is, not only a fixed host in an IP-based network by fusing the mobility technology of the mobile Internet protocol while maintaining the system structure of H.323. The present invention relates to a mobile internet protocol application method for a mobile internet telephony service enabling voice transmission from a moving host.

The conventional technology has been developed under the premise that it is fixed as a host on the Internet to the H.323 standard and has been researched to expand it. The integrated structure of the Internet network and the telephony network is a Standardization is underway around TPHON (Telecommunications and Internet Protocol Harmonization over Networks) and extensions to provide mobility in H.323 are standardized in Annex H, Annex I, and H.246 Annex E of H.323. Was pushing.

In addition, the mobile Internet protocol, which is a representative standard for managing mobility on the Internet, is based on a home agent and a foreign agent similar to GSM home location registrar (HLR) and visitor location registrar (VLR), respectively. Was offering roaming.

However, the mobile internet protocol causes a high handoff delay when there are many hops between the mobile node and the foreign agent, and loses data in transit until a new path is created between communicating nodes. Since the mobile node registers its location every time it moves to another network, if the network is moved frequently, the registration renewal messages put a lot of load on the network, and regional tunnel management has recently become a subject of much interest. Tunnel management) restricts the registration process only when the distance between the home network and the external network increases, but mobile internet telephony service is not considered.

Thus, Internet telephony (VoIP: Voice over IP), which is known as a technology for providing voice services over the Internet, is creating a new trend not only in the Internet, but also in the field of telephony. With the development, we have been developing technology for mobile computing environment, and mobility in communication network can be classified into user mobility, host mobility, and service mobility, and in terms of mobility of Internet host, for example, public telephone system (POTS) When attempting to connect from a terminal to an Internet terminal on the Internet, a Public Old Telephony System (POTS) terminal does not know whether the host on the Internet is a fixed node or a mobile node, and therefore mobility for such a mobile node. In communication with management technology and cell phone service There is a problem that must be solved for roaming and handoff problems for such services.

Accordingly, an object of the present invention is to propose an integrated structure for providing a mobile Internet service in an H.323 system environment, the integrated structure of the gatekeeper function expansion and database sharing structure It focuses on providing Internet telephony services to fixed and mobile hosts.

Another purpose is to register the location of mobile node in the integrated structure according to the internal and external movement. It is possible to perform the faster location update in the case of internal movement through the separate registration procedure. In this case, the packet loss rate can be reduced by updating the network layer location. Also, by applying the local tunneling method, it reduces the path optimization and unnecessary packet transmission in the region, and does not need a new entity to provide mobility. To maintain compatibility.

The purpose of the present invention is that H.323 of the ITU is designed based on a fixed host based on an Internet network, while providing real-time voice communication between the fixed host and a telephone of a fixed host or circuit-switched network. The H.323 protocol has a high handoff delay between the mobile node (MN), the correspondent node (CN), and the mobile agent (MA), which exist over many hops in the Internet. In the case of integrating the mobile internet protocol with the mobile internet protocol, a coherency problem for the mobile host location information cache for handover processing occurs when the mobile host moves to a new network. Therefore, when the mobile node changes its location, in order to support flexible handover, the protocol must be able to update the network node's cache and a temporary buffer must be allocated for packet storage. Handoff processing is performed when crossing cell boundaries, while global roaming is a mobile Internet telephony service that uses the Home Location Register (HLR) and the Visitor Location Register (VLR) to store mobile phone location information. A method of applying a mobile internet protocol for the present invention was achieved.

1 is a network configuration diagram for an H.323 mobile node configured in a method for applying a mobile internet protocol for mobile internet telephony service according to a preferred embodiment of the present invention.

2 is a diagram illustrating a registration process when a mobile node performs internal movement by a mobile internet protocol application method for mobile internet telephony service according to a preferred embodiment of the present invention.

3 is a registration process diagram when a mobile node performs external movement by the mobile internet protocol application method for mobile internet telephony service according to the preferred embodiment of the present invention.

4 is a flowchart illustrating registration when a mobile node moves by a mobile internet protocol application method for mobile internet telephony service according to a preferred embodiment of the present invention.

Description of the main parts of the drawing

1: PSTN or GSM 2, 2-1: Gateway (external and home)

3, 3-1: MGK (external and home) 4: Home agent

5: mobile node 6: foreign agent

7: phone network

Hereinafter, the configuration of the present invention will be described in detail with reference to the accompanying drawings for a preferred embodiment.

First, the present invention proposes an integrated model for providing mobility in an H.323 environment by extending existing registration area based location management and local tunnel registration method, and the main extension function of the present invention is a mobile agent (HA or FA). ) Is described in the Mobile Gate Keeper (MGK), which is combined with the gatekeeper defined in H.323 and used as follows to help the present invention.

MGK (Mobile GateKeeper): Mobile GateKeeper is a mobile gatekeeper that performs the functions of a mobile agent and a gatekeeper, and in order to effectively manage mobility of mobile nodes, the MGK of each region is configured of all mobile nodes and fixed nodes in its own region. Contains location information and handles updating of location information for internal movement.

Home Zone: The area where the H.323 terminal initially subscribed (registered).

Foreign zone: The area after the H.323 terminal has moved.

Internal movement: A mobile node moves from one subnet to another within a single region.

Outward movement: to move from one area to another.

Public Switched Telephone Network (PSTN): Telephone Network

GSM (Global System for Mobile communications): A variant of Time Division Multiple Access (TDMA) .Tunneling: Between two points on a network using encapsulation that appends a header or a header to a packet at the IP layer In order to enable communication, communication between the two points cannot be distinguished from normal packets and encapsulated packets, but devices at both ends that can unencapsulate can distinguish the original packets and create an invisible path on the Internet. Such a passage is called a tunnel because it can be made and communicated, and the transmission of data through the tunnel is tunneling.

1 is a network configuration diagram for an H.323 mobile node configured in a method for applying a mobile internet protocol for a mobile internet telephony service according to a preferred embodiment of the present invention. Internet telephone service provides PC-to-PC communication as well as PC-to-PC communication, so Internet phone service users need to connect the Internet network with the telecommunication network. It shows a network structure for maintaining the communication structure between them and managing mobility in the Internet network.

Also, a zone is a set of H.323 nodes managed by a single mobile gatekeeper 3 (MGK), similar to that defined in H.323.

However, this structure shows a new component called Mobile Gatekeepers 3, 3-1 (MGK) as well as the existing components, and is a Mobile Gate that operates as a Mobile Agent (MA) in the area currently managed by the Gatekeeper. The keeper 3 (MGK) not only maintains information about access points of subscribers leaving the home area and moving to the external network, but also maintains a home list of subscribers in the management area.

Each region contains only one gatekeeper and is connected to multiple subnets through routers, each subnet containing one or more mobile agents (external agent 6 (FA) or home agent (4) (HA)). Including a plurality of mobile terminals and fixed terminals.

In addition, the mobile gatekeeper 3 (MGK) performs address translation like the existing gatekeeper, provides call authentication control service, and performs call setup management such as routing to an appropriate area.

When the mobile node 5 (MN) moves from one subnet to another subnet, the mobile nodekeeper first performs location registration, and the mobile node 5 (MN) performs the registration processing in order to perform the registration processing. (3) (MGK) location information and external agent (FA) location information are required.

This information can be obtained through the periodic advertisement message of the mobile gatekeeper 3 (MGK) and the position advertisement of the mobile agent (the mobile gatekeeper 3 (MGK) position and the position of the mobile agent) and receive the advertisement message. The mobile node 5 may determine whether the location of the network to which it has moved is a home region or an external region, as well as an external agent 6 (FA) and a mobile gatekeeper 3 for performing registration. The location information of the MGK can be known.

The location information advertisement period of the mobile gatekeeper 3 (MGK) is set to be much longer than the advertisement period of the mobile agent on the subnet, which means that the location of the mobile gatekeeper 3 (MGK) in each region does not cause any particular problem. While is always valid.

When moving in a state where communication is interrupted, the mobile node 5 (MN) registers its location and the address of the mobile agent on the subnet with the mobile gatekeeper 3 (MGK) of the new network.

Here, the registered address of the mobile node 5 (MN) may use the address used in the home network without change, or use a new address assigned by the external agent 6 (FA).

The registration packet uses the registration packet and the advertisement packet defined in the existing mobile Internet protocol. The mobile gatekeeper 3 (MGK) in the external area transmits the registration packet to the mobile gatekeeper 3 (MGK) in the home area. Through the authentication procedure, the home mobile gatekeeper 3 (MGK) transmits an acknowledgment message to the external mobile gatekeeper 3 (MGK).

Here the RAS (Registration, Authorization, and Status) channel defined in H.225.0 is used.

FIG. 2 is a diagram illustrating a registration process when a mobile node performs external movement according to a method of applying a mobile internet protocol for mobile internet telephony service according to a preferred embodiment, when the mobile node 5 (MN) moves from one region to another subnet. In the advertisement message, the position of the external agent 6 (FA) and the position information of the mobile gatekeeper 3 (MGK) are known.

The mobile node 5 knows that it is an internal movement by comparing with the previously stored position of the mobile gatekeeper 3 (MGK). In the case of an internal movement, the mobile node 5 transmits a registration request message to the external agent, 6) FA sends a registration message to the home agent.

The home agent receiving the registration message updates the location information of the mobile node and tunnels and delivers the subsequent message to the external agent, and the home agent delivers the registration message to the mobile gatekeeper 3 (MGK). The mobile gatekeeper 3 (MGK) updates the location information list of the H.323 nodes existing in its area, and sends a response message directly to the external agent.

When the registration update is completed, the mobile gatekeeper 3 (MGK) tunnels all packets received by the mobile node on behalf of the home agent and transmits them to the external agent.

Thereafter, the mobile node 5 periodically transmits a location information update message to the external mobile gatekeeper 3 (MGK) in order to prevent the gatekeeper from deleting the location information over time.

When the mobile node 5 leaves the home area, it moves to a subnet within the outside area, and the mobile node 5 receives an advertisement message from an external agent 6 (FA) of the subnet where it is currently located and includes the subnet. By comparing the local information and the external agent location information with previously stored information, it is known to move to another region.

3 is a registration process diagram when a mobile node performs external movement according to a method of applying a mobile internet protocol for mobile internet telephony service according to a preferred embodiment.

The mobile node 5 transmits a registration request message to the external agent 6 (FA), the external agent 6 makes a registration request to the home agent, and the home agent is delivered to the mobile node 5 for a predetermined time. By passing the packets to the foreign agent 6 (FA) via tunneling, it is possible to reduce the loss for handoff.

The home agent updates the location information of the mobile node after receiving the registration request message, forwards the registration request message to the mobile agent of the home mobile gatekeeper 3 (MGK), and the home mobile gatekeeper 3 (MGK). Sends a response message along the reverse path.

The home mobile gatekeeper 3 (MGK) transmits a registration request (RRQ) to the external mobile gatekeeper 3-1 (MGK) and receives a registration request (RRQ) for H.323 registration. The external mobile gatekeeper 3-1 transmits a registration confirmation (RCF) or a registration reject (RRJ) to the mobile node and the home mobile gatekeeper (MGK).

The registration procedure between the external mobile gatekeeper 3-1 (MGK) and the home mobile gatekeeper 3 (MGK) is handled using the signaling defined in H.225, that is to say receive a registration acceptance (RCF). One mobile node 5 knows the completion of the registration procedure and connects to an external gateway to establish a new call.

However, in order to reduce packet loss due to handoff, the mobile node 5 must maintain the existing call setup until the new call setup is completed even after receiving a registration accept (RCF) message.

In the case of intra-regional mobility, no additional channel setup is required because the gateway used by the mobile node 5 is not changed. Therefore, the mobile node 5 maintains the existing call setup and passes through the home agent. It is necessary to deal with the case where the data transmitted and the data transferred directly from the home mobile gateway overlap.

Processing of such duplicate data can be solved through the sequence number of the transport layer or the network layer.

In the case of out-of-region mobile, the communication path with the other node should be changed to go through the external mobile gateway. In this way, the synchronization problem can be solved by matching the receiving path and the transmission path, and the mobile node 5 can You can handle this more effectively if you move it.

After the mobile node 5 moves out of the area as shown in FIG. 3, the mobile node 5 is processed similarly to a general call setup procedure through an external mobile gatekeeper 3-1 (MGK) and an external gateway.

When the mobile node 5 returns from the external agent jurisdiction to the home agent jurisdiction, or moves from the external agent jurisdiction to another external agent jurisdiction, the mobile node 5 must deal with the deregistration or call establishment termination of the mobile node.

The location registration of the mobile node 5 is handled using the deregistration request message of the mobile Internet protocol, and the update of the location information of the mobile gateway is also handled and another method of processing the deregistration is an internal timer of the mobile agent or the mobile gatekeeper. How to use

If the mobile agent and the mobile gatekeeper do not receive the location update information for a certain time from the completion of the registration request processing, the mobile agent and the mobile gatekeeper delete the registration information of the mobile node and the non-registration defined in the H.225 registered by the mobile gatekeeper. It is handled using a request (URQ: Unregistration Request) and Unregistration Confirm (UCF) or Unregistration Reject (URJ).

4 is a flowchart illustrating a registration flow when a mobile node moves by a method of applying a mobile internet protocol for mobile internet telephony service according to a preferred embodiment.

Transmitting a periodic advertising message of the external agent FA (S1);

Confirming whether the mobile node MN exists in the home area (S2);

Transmitting a registration message to an external agent FA in the home area (S3);

The external agent FA of the home area transmits a registration message to the home agent HA (S4);

The home agent HA transmits the received registration message to the home mobile gatekeeper MGK and tunnels the mobile node MN to the home area external agent FA (S5);

The home mobile gatekeeper MGK updates the location information of the mobile node MN and transmits a response message to an external agent FA in the home area (S6);

Sending, by the foreign agent FA in the home area, a response message to the mobile node MN (S7);

Transmitting a registration message to an external agent FA in an external region (S8);

The external agent FA of the external region transmits a registration message to the home agent HA of the home region (S9);

The home agent HA transmitting a registration message to a home home move gatekeeper MGK (S10);

The home mobile gatekeeper (MGK) updates the location of the mobile node (MN) according to the received registration message and transmits an H.323 registration request message to an external mobile gatekeeper (MGK) in an external outside area (S11);

The external mobile gatekeeper MGK transmits a registration accept or reject message to the mobile node MN and the home mobile gatekeeper MGK (S12);

A new call setup step (S13) using the call setup method of H.323;

The communication resume step (S14).

In step S1 of transmitting the periodic advertising message of the external agent FA, the external agent FA in the home area transmits the periodic advertising message.

The step S2 of checking whether the mobile node MN exists in the home area is to determine whether the mobile node MN exists in the outside area or the home area after receiving the periodic advertisement message of the external agent. will be.

In step S3, when the mobile node moves within the home area, the mobile node transmits a registration message to an agent outside the home area.

In step S4, the foreign agent FA of the home area transmits a registration message to the home agent HA. The foreign agent receiving the registration message sent by the mobile node homes the registration message for location registration of the mobile node. To the agent.

The home agent HA transmits the registration message received to the home mobile gatekeeper MGK and tunnels the mobile node MN to the home area external agent FA in step S5. It updates the location information of and tunnels the data arriving toward the mobile node to the agent outside the home area, and transmits the registration message received by the home mobile gatekeeper (MGK).

The home mobile gatekeeper (MGK) updates the location information of the mobile node (MN) and transmits a response message to the external agent (F6). The home mobile gatekeeper (MGK) updates the location information of the mobile node. And send a message to the mobile agent about the registration.

In step S7, the foreign agent FA transmits a response message to the mobile node MN, and transmits a registration response message received by the mobile agent to the mobile node.

The step (S8) of transmitting a registration message to the external agent FA of the external region is to transmit a registration message to the external agent of the external region when the mobile node exists in the external region.

The external agent FA of the external region transmits a registration message to the home agent HA (S9). The external agent transmits the received registration message to the home agent of the mobile node.

The home agent HA transmits a registration message to the home mobile gatekeeper MGK (S10). The home agent delivers the received registration message to the home mobile gatekeeper.

The home mobile gatekeeper (MGK) updates the location of the mobile node (MN) according to the received registration message and transmits an H.323 registration request message to the external mobile gatekeeper (MGK) (S11). Is to update the location of the mobile node according to the received registration message and send the H.323 registration request message to the external mobile gatekeeper.

The external mobile gatekeeper MGK transmits a registration accept or reject message to the mobile node MN and the home mobile gatekeeper MGK (S12). The external mobile gatekeeper accepts the registration in response to the registration request message. Or, sending a reject message to the mobile node and the home mobile gatekeeper.

Using the call setup method of H.323, a new call setup step (S13) is to change the communication path with the counterpart node through the external mobile gateway when the mobile node moves to an external region.

The communication resumption step (S14) is that communication is resumed by a process of transmitting a registration message to the FA of the home domain (S3) and a new call setup step (S13) using the call setup method of H.323. .

As described above, the present invention, unlike Annex H of H.323, proposes a mechanism for providing IP host mobility for an H.323 system using a mobile Internet protocol under a transport. The H.323 standard and the Mobile Internet Protocol standard have the effect of minimizing the need for changes and new features.

Claims (6)

The registration method when the mobile node moves by the mobile internet protocol application method for mobile internet telephony service Transmitting a periodic advertising message of the external agent FA (S1); Confirming whether the mobile node MN exists in the home area (S2); Transmitting a registration message to an external agent FA in the home area (S3); The external agent FA of the home area transmits a registration message to the home agent HA (S4); The home agent HA transmits the received registration message to the home mobile gatekeeper MGK and tunnels the mobile node MN to the home area external agent FA (S5); The home mobile gatekeeper MGK updates the location information of the mobile node MN and transmits a response message to an external agent FA in the home area (S6); Sending, by the foreign agent FA in the home area, a response message to the mobile node MN (S7); Transmitting a registration message to an external agent FA in an external region (S8); The external agent FA of the external region transmits a registration message to the home agent HA of the home region (S9); The home agent HA transmits a registration message to the home mobile gatekeeper MGK (S10); The home mobile gatekeeper (MGK) updates the location of the mobile node (MN) according to the received registration message and transmits an H.323 registration request message to an external mobile gatekeeper (MGK) in an external area (S11); The external mobile gatekeeper MGK in the outside area transmits a registration accept or reject message to the mobile node MN and the home mobile gatekeeper MGK (S12); A new call setup step (S13) using the call setup method of H.323; Method of applying a mobile internet protocol for mobile internet telephony service, characterized in that the communication resume step (S14). The method of claim 1, wherein the foreign agent FA of the home area transmits a registration message to the home agent HA, in which step S4 updates the location information of the mobile node to tunnel the subsequent message to the foreign agent. Method for applying the mobile Internet protocol for mobile Internet telephony service, characterized in that for transmitting. The method of claim 1, wherein the step (S3) of transmitting a registration message to the external agent (FA) in the home area, and the step (S4) of the external agent (FA) of the home area transmit a registration message to the home agent (HA). And, the home agent (HA) transmits the registration message received to the home mobile gatekeeper (MGK) and tunnels the mobile node (MN) to the home area foreign agent (FA) (S5), the home mobile gatekeeper (MGK) updates the location information of the mobile node (MN) and transmits a response message to the external agent (FA) (S6) when the registration is completed, the mobile gatekeeper is all received from the mobile node on behalf of the home agent A method of applying a mobile internet protocol for a mobile internet telephony service, characterized in that a packet is tunneled and transmitted to an external agent. 4. The mobile Internet telephone of claim 1 or 3, wherein the gatekeeper periodically transmits a location information update message from an external mobile gatekeeper to prevent the location information from being deleted by timeout. How to apply Mobile Internet Protocol for services. The method of claim 1, further comprising: transmitting a registration message to an external agent (FA) in the external region (S8), and transmitting a registration message to a home agent (HA) (S9); The home mobile gatekeeper (MGK) updates the location of the mobile node (MN) according to the received registration message and transmits an H.323 registration request message to the external mobile gatekeeper (MGK) (S11), and the external mobile gate. The keeper MGK transmits a registration acceptance or rejection message to the mobile node MN and the home mobile gatekeeper MGK (S12). After the Internet registration, the home mobile gatekeeper requests a registration from an external mobile gatekeeper ( An external mobile gatekeeper which transmits a registration request (RRQ) and a registration rejection (RRJ) to the mobile node and the home mobile gatekeeper to register H.323. Mobile internet How to Apply Mobile Internet Protocol for Telephone Service. 6. The method of claim 5, wherein the external mobile gatekeeper receiving the registration request (RRQ) sends a registration acceptance (RCF) by sending a registration accept (RCF) or a registration rejection (RRJ) to the mobile node and the home mobile gatekeeper. The received mobile node maintains the existing call setup until the new call setup is completed.