KR20080052051A - Handover Method in IP-based Wireless Network - Google Patents

Abstract

The present invention relates to a handover method in an IP (IP) -based wireless network, the step of receiving an IP address from a network node when the terminal accesses the network in the IP-based wireless network, and when the terminal is out of the network node area Handover to the state where the allocated IP address is maintained if the data is active in the state of transmitting and receiving data, and a new IP address from the network node of the new area if the terminal is in the idle state of transmitting and receiving data when it leaves the network node. And receiving a handover, wherein the terminal receives an IP in the IP management area and, if there is a session in progress, maintains the IP address regardless of the movement of the terminal, thereby changing the IP of the terminal. It has the advantage of avoiding time delay and data loss by handover.

Description

Handover method in IP-based wireless network {HANDOVER METHOD IN IP-BASED WIRELESS NETWORKS}

1 is a diagram illustrating a system for performing IP allocation and management in DHCP and location management in HA according to a WiBro service network configuration according to the prior art;

2 is a diagram illustrating a system for performing IP allocation and management of a terminal in a WAGW / DHCP and location management in a location server according to an embodiment of the present invention.

3 is a diagram illustrating a process of registering an IP address and registering an IP address when a terminal accesses a network in an IP-based wireless network according to an embodiment of the present invention;

4 is a diagram illustrating an IP management and location management process of a terminal when the terminal moves within an area of a network node to which the terminal assigns an IP address according to an embodiment of the present invention;

FIG. 5 is a diagram illustrating an IP management, location management, and handover process of a terminal when there is an ongoing data session when the terminal moves out of an area of a network node to which the terminal assigns an IP address according to an embodiment of the present invention.

The present invention relates to a handover method in an IP (IP) -based wireless network, and more particularly to a method for handover without changing the IP of the terminal in an IP-based wireless network including various wireless access technologies as well as portable Internet It is about.

With the development of wireless communication technology and the popularity of the Internet, IP-based wireless networks are spotlighted as next generation network systems. Various IP-based wireless networks such as 3GPP HSPA, 3GPP LTE, 3GPP2 EV-DO, mobile communication-based packet service system, WiBro combining mobile with fixed communication, next-generation wireless LAN, IEEE 802.16e, and IEEE 802.20 are emerging.

In the IP-based wireless network, IP is allocated to the terminal and managed, and location management according to the movement of the terminal is an important technical element to provide a seamless service to the user.

1 is a diagram illustrating a system for performing IP allocation and management in DHCP and location management in HA according to a WiBro service network configuration according to the prior art.

The Portable Subscriber Station (PSS) 11 connects to an Access Control Router (ACR) 13 that provides IP bearer services via a Radio Access System (RAS) 12. do. In this case, the user service device 11 receives an IP from the Dynamic Host Configuration Protocol (DHCP) 15 and performs a location management of the assigned IP by the home agent (HA) 14. The IP assigned to the Domain Name System (DNS) 16 is registered to map the identifier and the IP address of the user service device 11.

The user service device 11 may move to another wireless access device and connect to the new access control router 18 via, for example, a mobile access point (AP) device. At this time, the user service device 11 receives a new IP through DHCP 15, registers it with the HA 14, and updates the DNS 16.

In this situation, a new IP is allocated and the process of registering it with the HA takes a considerable time. When there are data sessions transmitted and received by the user service device, packet loss and delay may occur, thereby significantly degrading service quality.

In fact, in the case of a real-time service, when a delay of 150 msec or more occurs, the user is known to feel a deterioration in service quality. As described above, an IP is assigned according to the movement and the process of registering it with the HA is described. It takes several seconds and requires a new handover mechanism for real-time service.

Even if it is not a real-time service, the service quality is considerably lower for delay-sensitive services. In addition, there is a problem that the packet loss occurring during the movement is also quite large.

The GTP method, which is another method, has the advantage that the terminal always uses the same IP, but there is a disadvantage in that the data path is long through tunneling between the wireless access gateways when moving between the wireless access gateways, and only the 3GPP series wireless access system is supported. Generally not used.

The present invention has been proposed to solve such a conventional problem, and proposes a network system for suggesting a method for allocating and managing an IP address of a terminal and a location management method in an IP-based wireless network, and handover delay in a network system. The purpose of this paper is to propose a handover mechanism that minimizes packet loss while reducing packet loss.

The handover method in the IP-based wireless network according to the present invention for realizing the above object, the step of receiving an IP address from the network node when the terminal accesses the network in the IP-based wireless network, the terminal is the area of the network node Handover to the state where the allocated IP address is maintained when the data is active in the case of leaving the network, and from the network node in the new area when the terminal is in the idle state when the data is out of the network node. And handovering the new IP address.

According to the present invention, in the IP-based wireless network, the terminal is assigned an IP address when accessing the network. This IP address is used statically unless it moves out of the area of the network node that assigns it. If the terminal is out of the area of the network node that allocates the IP address, the IP address does not change when the terminal is in an active state of transmitting and receiving data. In this way, handover without interruption can be provided. If the terminal is in an idle state in which data is not transmitted or received, a new IP address is allocated from a network node of a new area.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. In addition, in describing the present invention, when it is determined that the detailed description of the related known configuration or function may obscure the gist of the present invention, the detailed description thereof will be omitted.

2 is a diagram illustrating a system for performing IP allocation and management of a terminal in a WAGW / DHCP and location management in a location server according to an embodiment of the present invention.

The user service device terminal 101 connects to a radio access gateway 103 that provides an IP bearer service through the radio access system 102. At this time, the user service device terminal 101 is assigned an IP from the DHCP function of the device of the wireless access gateway 103, the location management for the assigned IP is directly performed by the wireless access gateway 103. The IP assigned to the location server 104 is registered to map the identifier and the IP address of the user service device terminal 101.

The user service device terminal 101 may move to another radio access system device, for example, when a wireless connection is made through the radio access system 105, or when there is no data session exchanged by the user service device terminal 102. A new wireless access gateway 106 is connected. At this time, the user service device terminal 101 is assigned a new IP, the location management for the assigned IP is directly performed by the new radio access gateway 106. The IP assigned to the location server 104 is registered to map the identifier and the IP address of the user service device terminal 101.

When there is a data session exchanged by the user service device terminal 101, that is, in an active state, the wireless access system 105 may access and use the wireless access gateway 103 that the user service device terminal 101 has accessed and used before moving. Informs the movement of the user service device terminal 101. The radio access gateway performs a handover by establishing a data path with the user service apparatus terminal 101 to the new radio access system 105. This allows you to continue to service without changing the IP address. You can reduce the time lag associated with reassigning new IP addresses and registering them. In addition, packet forwarding may be performed by performing data forwarding through a data path for reducing packet loss between two radio access systems 102 and 105 to which the user service apparatus terminal 101 accesses.

3 illustrates a process of registering an IP address and registering an IP address when a terminal accesses a network in an IP-based wireless network according to an exemplary embodiment of the present invention.

The user service device terminal 101 requests a radio access connection to the radio access system 102 (S201). The radio access system 102 performs authentication and the like of the user service device terminal 101 and responds to the radio access connection request (S202). When the radio access connection is provided, the user service device terminal 101 is provided with a channel for connecting to the radio access system 102 to exchange data (S203). The radio access system 102 requests registration of the terminal to the radio access gateway 103 in order to inform the network of the registration of the user service device terminal 101 (S204). The radio access gateway 103 performs a task required for registration of the terminal and transmits the result to the radio access system 102 (S205). If the registration of the terminal is successfully performed, the radio access gateway 103 establishes a data path to the radio access system 102 and exchanges data with the user terminal through the path (S206). In order to map the identifier and the IP address of the user service device terminal 101, the wireless access gateway 103 registers the IP address assigned to the user terminal in the location server 104 (S207).

When the network registration of the user service device terminal 101 is completed as described above, the data transmitted to the user service device terminal 101 is transmitted to the wireless access gateway 103 managing the user terminal via the location server 104. do. The radio access gateway 103 has information about the radio access system 102 in which the user service device terminal 101 is currently located, and transmits data via the data path to the radio access system 102. The radio access system 102 receiving the data transmits data through a channel for the user service device terminal 101 so that the user terminal finally receives the data.

4 illustrates an IP management and location management process of a terminal when the terminal moves within an area of a network node to which the terminal assigns an IP address according to an exemplary embodiment of the present invention.

Through the network registration process of FIG. 3, the user service device terminal 101 becomes an IP bearer connection to the radio access gateway 103 through the radio access system 102 (S203 and S206). In the area managed by the wireless access gateway 103, which is a network node to which the user service device terminal 101 which received the service through the data path generated in this way, is assigned a new IP address, the terminal establishes a wireless access connection. )

The user service device terminal 101 reports the state of the radio access connection to the radio access system 102 (S301). The handover of the terminal is requested to the new radio access system 102 based on the collected information (S302). The new radio access system 102 determines whether to receive the terminal and performs a handover response to the previous radio access system 102 (S303). Once the handover is determined, the previous radio access system 102 may establish a data path during the handover to the new radio access system 102 to prevent data loss occurring during the handover (S304). In operation S305, the UE is instructed to perform handover. The user terminal performs a radio access connection with the new radio access system 102 (S306). The new radio access system completes the radio access connection with the user terminal (S307), and establishes a radio data path to the user terminal (S308). Then, the wireless access gateway 103 is notified that the user terminal is currently registered with itself (S309). The radio access gateway 103 processes the registration request (S310), releases the data path (S206) of the user terminal through the previous radio access system 102, and releases the user terminal through the new radio access system 102. The data path is set (S311). In this way, the IP bearer path to the moved user terminal is completed (S308, S311).

FIG. 5 illustrates an IP management, location management and handover process of a terminal when there is an ongoing data session when the terminal moves out of an area of a network node to which the terminal assigns an IP address according to an embodiment of the present invention. .

Through the handover process of FIG. 4, the user service device terminal 101 becomes an IP bearer connection to the radio access gateway 103 through the radio access system 102 (S308 and S311). The new radio managed by the other radio access gateway 106 out of the area managed by the radio access gateway 103, which is a network node to which the user service device terminal 101 which received the service through the data path thus generated, is assigned a IP address. A wireless access connection may be made to the access system 105. In this case, when there is no data session in progress, that is, in the idle state, IP management and location management of the terminal are the same as in the process of FIG. If there is an ongoing data session, the IP management, location management and handover process of the UE are as follows.

The user service device terminal 101 reports the state of the radio access connection to the radio access system 102 (S401). The handover of the terminal is requested to the new radio access system 105 based on the collected information (S402). The new radio access system 105 determines whether to receive a terminal and performs a handover response to the previous radio access system 102 (S403). Once the handover is determined, the previous radio access system 102 may establish a data path during the handover to the new radio access system 105 to prevent data loss occurring during the handover (S404). In operation S405, the user terminal is instructed to perform handover. The user terminal performs a wireless access connection with the new radio access system 105 (S406). The new radio access system 105 completes the radio access connection with the user terminal (S407), and establishes a radio data path to the user terminal (S408). In operation S409, the wireless access gateway 103 to which the IP address of the user terminal is first assigned is notified to the user. In this case, the new radio access system 105 may know the information of the radio access gateway 103 from the information transmitted from the user service device terminal 101. The radio access gateway 103 processes the registration request (S410), releases the data path S311 of the user terminal through the previous radio access system 102, and releases the user terminal through the new radio access system 105. A data path is set (S411). In this way, the IP bearer path to the moved user terminal is completed (S408 and S411).

It has been described so far limited to one embodiment of the present invention, it is obvious that the technology of the present invention can be easily modified by those skilled in the art. Such modified embodiments should be included in the technical spirit described in the claims of the present invention.

As described above, the present invention proposes a network system for presenting a method for allocating and managing an IP address of a terminal and a location management method in an IP-based wireless network, and reduces a packet loss while minimizing handover delay in a network system. Present an over mechanism.

The present invention can be generally used as an IP allocation and management method of a terminal in various IP-based wireless networks such as 3GPP HSPA, 3GPP LTE, 3GPP2 EV-DO, WiBro, next generation WLAN, IEEE 802.16e, IEEE 802.20.

In particular, the terminal is assigned an IP within the IP management area, and if there is a session in progress, the terminal maintains the IP address regardless of the movement of the terminal. It has the effect of preventing data loss.

Claims (6)

(a) receiving an IP address from a network node when a terminal accesses a network in an IP-based wireless network; (b) handover to the state where the allocated IP address is maintained if the terminal is in an active state of exchanging data when the terminal leaves the network node; (c) handover by receiving a new IP address from a network node of a new area if the terminal is in an idle state in which the data is not transmitted or received when the terminal leaves the network node; Handover method in IP-based wireless network comprising a. The method of claim 1, In step (a), (a1) requesting a radio access connection to a radio access system when the terminal accesses the network; (a2) the radio access system accepting the radio access connection request of the terminal and establishing a radio data path; (a3) the radio access system requesting a network registration of the terminal to a radio access gateway which is the network node; (a4) setting, by the radio access gateway, a network registration request of the terminal and assigning the IP address to the terminal and then setting an IP bearer path to the terminal; (a5) updating, by the radio access gateway, a mapping of the IP address assigned in step (a4) to the location server and an identifier corresponding to the terminal; Handover method in IP-based wireless network comprising a. The method of claim 1, The handover method, (d) handover to the state where the allocated IP address is maintained when the terminal moves without leaving the network node; Handover method in IP-based wireless network further comprising. The method of claim 1, In step (d), (d1) the terminal reporting a state of a radio access connection to a first radio access system; (d2) requesting handover of the terminal to a second radio access system based on the collected information by the first radio access system; (d3) the second radio access system determining whether to receive the terminal and performing a handover response to the first radio access system; (d4) when the handover is determined, the first radio access system establishes a data path during the handover to the second radio access system to prevent data loss occurring during the handover; (d5) the first radio access system instructing the terminal to perform handover; (d6) the terminal performing a radio access connection with the second radio access system; (d7) establishing, by the second radio access system, a radio data path to the terminal; (d8) the second radio access system notifying a radio access gateway that is the network node that the terminal is currently registered with itself; (d9) the radio access gateway processing the registration request of the terminal, releasing the data path of the terminal through the first radio access system, and establishing a data path of the terminal through the second radio access system; Handover method in IP-based wireless network comprising a. The method of claim 1, In step (b), (b1) the terminal reporting a state of a radio access connection to a first radio access system; (b2) requesting handover of the terminal to a second radio access system based on the collected information by the first radio access system; (b3) the second radio access system determining whether to receive the terminal and performing a handover response to the first radio access system; (b4) if the handover is determined, the first radio access system establishes a data path during the handover to the second radio access system to prevent data loss occurring during the handover; (b5) instructing the terminal to perform handover by the first radio access system; (b6) the terminal performing a radio access connection with the second radio access system; (b7) establishing, by the second radio access system, a radio data path to the terminal; (b8) the terminal notifying the second radio access system of information of the radio access gateway, which is the network node to which its IP address is assigned; (b9) the second radio access system notifying the radio access gateway that the terminal is currently registered with itself; (b10) the radio access gateway processing a registration request of the terminal, releasing a data path of the terminal through the first radio access system, and establishing a data path of the terminal through the second radio access system; Handover method in IP-based wireless network comprising a. The method of claim 1, Step (c) is (c1) the terminal moving to an area managed by a new radio access gateway, which is the network node that has not assigned its IP address, requesting a radio access connection to a new radio access system; (c2) the new radio access system accepting a radio access connection request of the terminal and establishing a radio data path; (c3) the new radio access system requesting network registration of the terminal from the new radio access gateway; (c4) the new radio access gateway processes a network registration request and allocates a new IP address to the terminal and establishes an IP bearer path to the terminal; (c5) the new radio access gateway updating the mapping of the newly assigned IP address to the location server and an identifier corresponding to the terminal; Handover method in IP-based wireless network comprising a.

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