KR101399033B1 - Apparatus and method for ip mobility in wireless communication system - Google Patents

Abstract

The present invention relates to providing IP (Internet Protocol) mobility, and in a system for providing IP mobility in a wireless communication system, a first binding update request message is received from a new foreign agent, and when a load is smaller than a threshold, A home agent for requesting tunneling deletion with the mobile node by transmitting a binding deletion request message to a previous foreign agent and a gateway bound to the node, And deleting the tunneling to the previous foreign agent and the mobile node when receiving the binding deletion request message. The mobile node sets a dynamic routing path while ensuring service continuity when the mobile node moves, Solve load balancing (load balancing) issues and packet fragmentation (fragmentation) of the problem when using the blood to provide the advantage of improving the continuity and quality of service of the service provider.

Dynamic NAT, IP mobility, Mobile IP, HA, FA, GW.

Description

[0001] APPARATUS AND METHOD FOR PROVIDING IP MOBILITY IN WIRELESS COMMUNICATION SYSTEM [0002]

The present invention relates to provision of IP mobility and, as a mobile node (or a terminal) moves in a wireless communication system, an optimal node for providing a service to a mobile node is changed from time to time, thereby resolving difficulties in route re- To an apparatus and method for enhancing the quality of a call.

Generally, in order to support mobility using IP protocol, IP mobility is provided by using IP tunneling method of Mobile IP protocol to maintain service continuity.

Alternatively, in order to solve the problem of the bypass route, which is a disadvantage of the mobile IP scheme, the service node provides NAT mobility using NAT (Network Address Translaton).

In the existing mobile IP technology, since the path is always reset via the first node (HA), the burden of the initial node is increased, and there is a problem that a delay in the network path occurs due to the overload.

Mobile IP technology increases the packet size compared to the existing IP packet at the time of IP encapsulation, so that fragmentation of the additional IP packet due to the maximum size restriction of the MTU (Maximum Transmission Unit) .

In the NAT method (single NAT technology), it is possible to solve the bypass problem caused by the mobile IP. However, for the existing service, which is not a new service started after the application of the NAT, bi-casting), there is a problem that the continuity of existing services can not be guaranteed.

It is an object of the present invention to provide an apparatus and a method for providing IP mobility in a wireless communication system.

It is another object of the present invention to provide an apparatus and method for solving an existing load balancing problem and ensuring service continuity by setting a dynamic NAT tunnel on an end-to-end path in a wireless communication system.

According to a first aspect of the present invention, there is provided a system for providing IP mobility in a wireless communication system, the method comprising: receiving a first binding update request message from a new foreign agent and, when the load is smaller than a threshold value, A home agent for requesting tunneling deletion with the mobile node by transmitting a binding deletion request message to a previous foreign agent and a gateway bound to the mobile node, And a gateway for deleting the tunneling to the previous foreign agent and the mobile node when the binding deletion request message is received.

According to a second aspect of the present invention, there is provided a method for providing IP mobility in a wireless communication system, the method comprising: receiving a first binding update request message from a new foreign agent; Requesting tunneling deletion with the mobile node by transmitting a binding deletion request message to a previous foreign agent and a gateway bound to the mobile node; and performing a tunneling deletion request with the previous foreign agent and the gateway, And deleting tunneling for the previous foreign agent and the mobile node when the binding deletion request message is received from the home agent.

The present invention solves the problem of load balancing and packet fragmentation at the time of using the existing mobile IP by providing a dynamic routing path while guaranteeing service continuity when the mobile node moves, .

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings. In the following description, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will now be described by way of an apparatus and method for providing IP mobility in a wireless communication system.

The present invention relates to a method and system for managing a home network on a mobile network composed of a home agent (HA), a foreign agent (FA), a gateway (GW), a mobile node (MN), and a correspondent node (CN) And a dynamic NAT tunnel between the home agent and the adjacent gateways and foreign agents.

1 is a diagram illustrating a network configuration according to an embodiment of the present invention.

Referring to FIG. 1, there are two types of tunnels. One is a tunnel between each gateway 105 and 109 and the foreign agent 130 and the other is a tunnel between the home agent 120 and the foreign agent 130. [

When the load of the home agent 120 exceeds a predetermined threshold value, the home agent 120 establishes and uses a tunnel between one of the gateways 105 and 109 and the foreign agent 130, .

When the load of the home agent 120 decreases, the home agent 120 may teardown a tunnel between one of the gateways 105 and 109 and the foreign agent 130 .

Here, tunneling is possible by using the NAT technique (substituting the destination address) in the start node and the end node of the tunneling, respectively.

The starting node of the tunneling replaces the existing destination address with an IP address (care-of address) corresponding to the network address of the end node of the tunneling. At the end node of the tunneling, the care-of address is replaced with the original destination address.

The home agent 120 is in an initiated state without tunneling, in a home agent tunnel (HA-Tunneled) state in which only tunneling between the home agent 120 and the foreign agent 130 is established, (GW-Tunneled) state established in the tunneling between the gateway and the foreign agents 105 and 109 by a load balancing mechanism of the gateway 105 and the foreign agent 105.

Three (Init, HA-Tunneled, GW-Tunneled) states of the home agent 120 are set as message exchanges for tunnel establishment, and the process will be described with reference to FIG.

2 is a diagram illustrating a message exchange process according to a state of a home agent according to an embodiment of the present invention.

2A, there is shown a home agent tunnel state (HA-Tunneled) in which tunneling is established between a home agent 202 and a foreign agent 206, 208, )to be.

After receiving the advertisement message of the new foreign agent (FA_new) 206, the mobile node 210 determines the movement to the new foreign agent (FA_new) 206 and then transmits the new foreign agent FA_new 206 to the new foreign agent (FA_new) 206 (Step 1). The NAT Tunneling Update Request message is used to update the current tunnel by changing the end of the tunnel.

The new foreign agent FA_new 206 transmits a NAT Binding Update Request message to the home agent 202 in order to update the tunnel to the mobile node 210 (step 2) .

The NAT binding update request message is transmitted to the mobile node 210 and the new foreign agent FA_new (FA_new) 208 by binding a binding cache bound to the existing mobile node 210 and the previous foreign agent FA_old 208 206 < / RTI > to the binding cache.

The home agent 202 receives the NAT binding update request message, updates the binding cache, and transmits a NAT Binding Update Response message including a binding update result to the new foreign agent FA_new. (Step 3).

Thereafter, the new foreign agent (FA_new) 206 analyzes the binding update result to generate a tunnel, and transmits a NAT Tunneling Update Response message including a tunneling update (creation) result to the mobile node (Step 4).

Thereafter, the state of the home agent 202 becomes a home agent tunnel (HA-Tunneled) state (step b).

Here, if the binding is successful, a tunnel between the home agent 202 and the FA_old 208 is updated with a tunnel between the home agent 202 and the new foreign agent (FA_new) do. That is, a packet destined for the mobile node 210 passes through a tunnel between the home agent 202 and the new foreign agent 206, and then is transmitted to the mobile node 210.

When the packet passes through the tunnel, the destination address of the external packet is the IP address of the new foreign agent (FA_new) 206, which is the end of the new tunnel, and the destination address of the internal packet is And becomes the address of the mobile node 210. The binding cache update process is also performed in the new foreign agent (FA_new) 206 and the previous foreign agent (FA_old) 208.

2B illustrates a HA-Tunneled state in which tunneling between the home agent 202 and the foreign agents 206 and 208 is established. Here, the home agent is in an initial state (step a) to be.

After receiving the advertisement message of the new foreign agent (FA_new) 206, the mobile node 210 makes a decision to move to the new foreign agent (FA_new) 206 and then sends the new foreign agent (FA_new) To the new foreign agent (FA_new) 206, a NAT Tunneling Update Request message for updating the current tunnel (Step 1).

The new foreign agent FA_new 206 transmits a NAT Binding Update Request message to the home agent 202 in order to update the tunnel to the mobile node 210 (step 2) .

The NAT binding update request message is transmitted to the mobile node 210 and the new foreign agent FA_new (FA_new) 208 by binding a binding cache bound to the existing mobile node 210 and the previous foreign agent FA_old 208 206 < / RTI > to the binding cache.

The home agent 202 receives the NAT binding update request message, updates the binding cache, and then transmits a NAT binding deletion request to delete the existing binding cache held by the previous foreign agent (FA_old) (Binding Teardown Request) message to the previous foreign agent (FA_old) 208 (step 3).

The previous foreign agent FA_old 208 deletes the associated binding cache with the mobile node 210 and transmits a NAT Binding Teardown Response message including the result to the home agent 202 (Step 4). Also, the previous foreign agent (FA_old) 208 releases the existing tunnel.

Then, the home agent 202 transmits a NAT Binding Update Response message including the binding update result to the new foreign agent (FA_new) 206 (step 5).

Then, the new foreign agent (FA_new) 206 analyzes the binding update result, creates a tunnel, and transmits a NAT Tunneling Update Response message including a tunneling update result to the mobile node 210, (Step 6).

Thereafter, the state of the home agent maintains a home agent tunnel (HA-Tunneled) state (step b).

If the binding is successful, a tunnel between the home agent 202 and the previous foreign agent (FA_old) 208 is updated with a tunnel between the home agent 202 and the new foreign agent (FA_new) do.

That is, a packet destined for the mobile node 210 passes through a tunnel between the home agent 202 and the new foreign agent (FA_new) 206, and then is transmitted to the mobile node 210.

When the packet passes through the tunnel, the IP address is passed through the IP encapsulation process. The destination address of the external packet is the IP address of the new foreign agent, which is the end of the new tunnel. The destination address of the internal packet is the address of the mobile node do.

The binding cache update process is also performed in the new foreign agent (FA_new) 206.

Referring to FIG. 2C, the home agent 202 and the gateway 204 show a tunnel state change process (HA-Tunneled- > GW-Tunneled) -Tunneled (step a).

The home agent 202 sends a NAT Binding Update Request message to the gateway 204 to change the HA-Tunneled state to a GW-Tunneled state (Step 1).

The gateway 204 receives the NAT binding update request message and acquires the binding information (binding information between the mobile node and another node) included in the NAT binding update request message and reflects the binding information in its binding cache .

Thereafter, a NAT Binding Update Response message including a binding result is transmitted to the home agent 202 (step 2).

Thereafter, the home agent 202 changes to a gateway tunnel (GW-Tunneled) state (step b).

Referring to FIG. 2D, the home agent 202 tears down the tunnel between the home agent 202 and the old foreign agent (FA_old) 208. First, the home agent 202 accesses a home agent tunnel (HA-Tunneled) (Step a).

The mobile node 210 transmits a NAT Tunneling Update Request message to the home agent 202 in order to change the current tunnel state (HA Tunneled) to GW-Tunneled (Step 1).

The home agent 202 may obtain information (IP address or the like) about a previous foreign agent (FA_old) 208 to tear down the tunnel from the binding cache for the mobile node 210, Tunneling update request message.

Then, the home agent 202 transmits a NAT Binding Teardown Request message to the previous foreign agent (FA_old) 208 in order to tear down the tunnel to the mobile node 210 (Step 2).

The NAT binding tier down request message is a message for updating an existing binding cache and a tunnel bound to the mobile node 210 and the previous foreign agent FA_old 208.

The previous foreign agent FA_old 208 then updates (deletes) and binds the binding cache and tunnel bound to the mobile node 210 and the previous foreign agent FA_old 208 And transmits a NAT Binding Teardown Response message to the home agent 202 (step 3).

The home agent 202 then updates the binding cache between the mobile node 210 and the previous foreign agent FA_old 208 in response to the previous foreign agent FA_old 208, And transmits a NAT Tunneling Update Response message to the mobile node 210 (step 4).

Then, the home agent 202 changes its state to an initial state (step b).

Referring to FIG. 2E, a process for tearing down a tunnel between the gateway 204 and the foreign agent 208 is shown. Here, the home agent 202 is in a gateway tunnel (GW-Tunneled) state ). Here, the tunnel represents a tunnel between the gateway 204 and the old foreign agent (FA_old) 208.

The mobile node 210 transmits a NAT Tunneling Update Request message to the home agent 202 to tear down the current tunnel state (step 1).

The home agent 202 transmits information (IP address and the like) to the previous foreign agent (FA_old) 208 to tear down the tunnel and information (IP address etc.) about the gateway 204 to the mobile node 210 ) From the binding cache for the NAT tunneling update request message, or may be obtained in the NAT tunneling update request message.

Then, the home agent 202 transmits a NAT Binding Teardown Request message to the gateway 204 to tear down the tunnel to the mobile node 210 (step 2).

The gateway 204 then updates (deletes) the binding cache and tunnel bound to the mobile node 210 and the previous foreign agent (FA_old) 208, and in response returns the NAT binding tier And transmits a NAT Binding Teardown Response to the home agent 202 (step 3).

In step 4, the home agent 202 transmits a NAT Tunneling Update Response message including the tunnel update result to the MN 210 in response.

Then, the home agent 202 transmits a NAT Binding Teardown Request message to the last foreign agent (FA_old) 208 in order to tear down the tunnel to the mobile node 210 (Step 5).

The last foreign agent (FA_old) 208 then updates (deletes) the tunnel between the gateway 204 and itself to the mobile node 210 and sends a NAT Binding Tier Down Response Teardown Response) to the home agent 202 (Step 6).

Then, the home agent 202 changes its state to an initial state (step b).

Referring to FIG. 2F, a tunnel state change process (GW-Tunneled - > HA-Tunneled) is shown in the home agent 202 and the gateway 204, and the home agent 202 transmits a gateway agent tunnel -Tunneled state (step a).

The home agent 202 sends a NAT Binding Update Request message to the gateway 204 to change the gateway tunnel state to a HA-Tunneled state (Step 1).

The gateway 204 receives the NAT binding update request message and acquires the binding information (binding information between the mobile node and another node) included in the NAT binding update request message and reflects the binding information in its binding cache .

Then, the home agent 202 performs tunneling on a packet to be transmitted / received in place of the gateway 204. [ That is, it returns to the original state.

Thereafter, a NAT Binding Update Response message including a binding result is transmitted to the home agent 202 (step 2).

Thereafter, the home agent 202 changes to a home agent tunnel (HA-Tunneled) state (step b).

3 is a diagram illustrating a process of changing a gateway tunnel (GW-Tunneled) according to an embodiment of the present invention to a home agent tunnel (HA-Tunneled).

Referring to FIG. 3, the home agent is a gateway tunnel state (GW-Tunneled) (step a). After receiving the advertisement message of the new foreign agent (FA_new) 306, the mobile node 310 makes a decision to move to the new foreign agent (FA_new) 306, And transmits a NAT Tunneling Update Request message for updating the current tunnel to the new foreign agent (FA_new) 306 (Step 1).

The new foreign agent FA_new 306 transmits a NAT Binding Update Request message to the home agent 302 in order to update the tunnel for the mobile node 310 ).

The NAT binding update request message is transmitted to the mobile node 210 and the new foreign agent FA_new (FA_new) by binding a binding cache bound to the existing mobile node 310 and the previous foreign agent FA_old 308 306 < / RTI > to the binding cache.

The home agent 302 receives the NAT binding update request message, updates the binding cache, and then deletes the existing binding cache held by the previous foreign agent (FA_old) 308 (FA_old) 308 (Step 3). The Binding Teardown Request message is transmitted to the FA_old 308.

The previous foreign agent FA_old 308 deletes the associated binding cache with the mobile node 310 and transmits a NAT Binding Teardown Response message including the result to the HA 302 (Step 4).

Then, the home agent 302 transmits a NAT Binding Update Response message including the binding update result to the new foreign agent (FA_new) 306 (step 5).

The new foreign agent (FA_new) 306 analyzes the binding update result and transmits a NAT Tunneling Update Response message including the tunneling update result to the MN 310 (6) step).

If the binding is successful, a tunnel between the gateway 304 and the FA_old 308 is established as a tunnel between the home agent 302 and the new foreign agent (FA_new) .

That is, a packet destined for the mobile node 310 passes through a tunnel between the home agent 302 and the new foreign agent (FA_new) 306, and then is transmitted to the mobile node 310.

When the packet passes through the tunnel, the destination address of the external packet is the IP address of the new foreign agent (FA_new) 306, which is the end of the new tunnel, and the destination address of the internal packet is And becomes the address of the mobile node 310.

The binding cache updating process is also performed in the new foreign agent (FA_new) 306.

Then, the home agent 302 transmits a NAT Binding Teardown Request message to the gateway 308 in order to tear down the tunnel to the MN 310 (Step 7).

Then, the gateway 308 deletes the tunnel information for the MN 310 and transmits a NAT Binding Teardown Response message to the HA 202 in response to the MN binding response (Step 8) .

Then, the home agent 302 transmits a NAT Binding Teardown Request message to the last foreign agent (FA_old) 208 in order to tear down the tunnel to the MN 310 (Step 9).

Then, the last foreign agent FA_old 208 deletes the information about the tunnel between the gateway 308 and itself for the mobile node 310 and transmits a NAT Binding Teardown response To the home agent 302 (step 10).

Thereafter, the home agent 202 changes to a home agent tunnel (HA_Tunneled) state (step b)

The destination IP address of the packet transmitted from the gateway (or the home agent) to the new foreign agent FA_new is canceled with each other through the gateway (or the home agent) and the foreign agent, The service can be provided without change.

The NAT tunnel of the present invention can be used not only in a tunnel between a home agent and a new foreign agent but also in a tunnel between a gateway and an external agent depending on the load state of the home agent. Therefore, performance degradation or network congestion during overloading, The situation can be prevented.

In addition, since only the replacement of the destination address of the existing IP packet is required, dynamic overhead does not occur.

4 is a block diagram of a mobile node, a home agent, a gateway, and a foreign agent according to an embodiment of the present invention. One of the main advantages of the block configuration for the nodes is the communication interface. In general, the mobile node and the foreign agent include a wireless interface. In particular, the foreign agent considers both of the wireless interfaces.

4, the mobile node, the home agent, the gateway, and the foreign agent include a communication interface 410, a control unit 420, a storage unit 430, and a mobility management unit 440.

The communication interface 410 is a module for communicating with other nodes, and includes a radio processing unit and a radio baseband processing unit. The radio processor converts the signal received through the antenna into a baseband signal and provides the baseband signal to the radio baseband processor. The baseband processor converts the baseband signal from the radio baseband processor into a radio signal, Lt; / RTI >

The communication interface 410 includes a wired processing unit and a wired baseband processing unit. The wired processing unit converts the signal received through the wired path into a baseband signal and provides the baseband signal to the wired baseband processing unit. The wired processing unit changes the baseband signal from the wired baseband processing unit to a wired signal so that the baseband signal can be transmitted on the actual wired path Through the antenna.

The controller 420 controls the overall operation of the terminal. In particular, the mobility management unit 440 according to the present invention.

The storage unit 430 stores a program for controlling the overall operation of the node and temporary data generated during program execution.

In the case of the mobile node, the mobility management unit 440 updates tunneling by transmitting a corresponding message when a tunneling update event occurs (e.g., when a new advertisement message is received and movement is determined).

In the case of the foreign agent, the mobility management unit 440 receives a message transmitted from the mobile node, analyzes the message, transmits a message for tunneling and binding update to the gateway or the home agent, receives the result, And performs binding update, and transmits the result to the mobile node.

In the case of the home agent, the mobility management unit 440 receives and analyzes the message transmitted by the foreign agent or the gateway, performs tunneling and binding update, and transmits the result to the foreign agent or the gateway. Then, as described above, the home agent tunnel state or the gateway tunnel state is determined according to the load according to the threshold, and the corresponding message is transmitted to the gateway or the foreign agent to change to the corresponding state.

In the case of the gateway, the mobility management unit 440 receives and analyzes a message transmitted by the foreign agent or the home agent, performs tunneling and binding update, and transmits the result to the foreign agent or the home agent. When the tunnel state change message is received from the home agent as described above, the tunnel state is changed.

In the above-described block configuration, the control unit 420 may perform the functions of the mobility management unit 440. [ In the present invention, these are separately constructed and described in order to describe each function separately.

Accordingly, when the product is actually implemented, the control unit 420 may process all the functions of the mobility management unit 440, or the control unit 420 may process only a part of the functions.

While the present invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not limited to the disclosed embodiments, but is capable of various modifications within the scope of the invention. Therefore, the scope of the present invention should not be limited by the illustrated embodiments, but should be determined by the scope of the appended claims and equivalents thereof.

1 is a diagram illustrating a network configuration according to an embodiment of the present invention;

2 is a diagram illustrating a message exchange process according to a state of a home agent according to an embodiment of the present invention;

FIG. 3 is a diagram illustrating a process of changing a gateway tunnel (GW-Tunneled) according to an embodiment of the present invention to a home agent tunnel (HA-Tunneled)

4 is a block diagram of a mobile node, a home agent, a gateway, and a foreign agent according to an embodiment of the present invention.

Claims (10)

A system for providing IP mobility in a wireless communication system, When receiving a first binding update request message from a new foreign agent and transmitting a binding deletion request message to a previous foreign agent and a gateway bound to the mobile node when the load is smaller than the threshold, An agent, And a gateway for deleting the tunneling to the previous foreign agent and the mobile node when the binding deletion request message is received from the home agent during tunneling to the mobile node together with the previous foreign agent . The method according to claim 1, The home agent receives the first binding update request message from the new foreign agent and transmits a second binding update request message to the previous foreign agent bound to the mobile node when the load is smaller than the threshold, And receives the response message for the second binding update request message and transmits the response message to the new foreign agent by including the result in the response message for the first binding update request message. 3. The method of claim 2, Wherein the mobile node transmits a first binding update request message to the home agent to request a binding cache and tunneling update for the mobile node when the tunneling update request message is received from the mobile node, Further comprising a new foreign agent for adding and updating a binding cache and tunneling for the mobile node when the response message is received, and transmitting the result to the mobile node by including the result in a response message for the tunneling update request message ≪ / RTI > 3. The method of claim 2, When receiving the second binding update request message from the home agent, deleting the binding with the mobile node, deleting tunneling with the mobile node when receiving the binding deletion request message from the home agent Further comprising: a last foreign agent for generating a response message for the second binding update request message including a result of deletion of a binding with the mobile node and transmitting the response message to the home agent. 3. The method of claim 2, Further comprising a mobile node for receiving the advertisement message from the new foreign agent and transmitting the tunneling update request message to the new foreign agent when the mobile agent has decided to move to the new foreign agent. A method for providing IP mobility in a wireless communication system, When the home agent receives the first binding update request message from the new foreign agent and the load is smaller than the threshold, the home agent transmits a binding deletion request message to the previous foreign agent and the gateway bound to the mobile node to request tunneling deletion with the mobile node And, And deleting tunneling for the previous foreign agent and the mobile node when the gateway receives the binding delete request message from the home agent during tunneling to the mobile node together with the previous foreign agent ≪ / RTI > The method according to claim 6, When the home agent receives the first binding update request message from the new foreign agent and the load is smaller than the threshold, the home agent transmits a second binding update request message to the previous foreign agent bound to the mobile node, Requesting the deletion of the < RTI ID = 0.0 & Further comprising the step of receiving a response message for the second binding update request message and including the result in a response message for the first binding update request message to the new foreign agent. 8. The method of claim 7, Requesting a binding cache and a tunneling update for the mobile node by transmitting the first binding update request message to the home agent when the new foreign agent receives a tunneling update request message from the mobile node; When the new foreign agent receives the response message for the first binding update request message, it adds and updates the binding cache and tunneling for the mobile node and includes the result in the response message for the tunneling update request message To the mobile node. ≪ Desc / Clms Page number 21 > 8. The method of claim 7, Performing a binding deletion with the mobile node when the last foreign agent receives the second binding update request message from the home agent; When the last foreign agent receives the binding deletion request message from the home agent, deletes the tunneling with the mobile node, and transmits a response to the second binding update request message including the deletion result of the binding with the mobile node And generating and sending a message to the home agent. 8. The method of claim 7, Further comprising the step of transmitting the tunneling update request message to the new foreign agent when the mobile node receives the advertisement message from the new foreign agent and determines to move to the new foreign agent.

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