KR20070080991A - Method for establishing data tunnel between ran and user plane gateway in wireless telecommunications system and therefor system - Google Patents

Abstract

A data tunnel formation method between an RAN(Radio Access Network) and a UP-GW(User Plane Gateway) in a wireless communication system and a system thereof are provided to form a direct data bearer between the RAN and the UP-GW, thereby reducing an unnecessary signaling overhead for forming a data tunnel. A CP(Control Plane)-GW(105) receives a paging request message which includes bearer information of a UP-GW(107)(111). The bearer information is removed from the paging request message, and the paging request message is broadcasted to connectable RANs(103)(113,115). Through one of the RANs connectable with a UE(User Equipment)(101), a service request message corresponding to the paging request message is received from the UE(117,119). An RAB(Radio Access Bearer) is set with the RAN by responding to the service request message, and bearer information of the RAB is obtained from the RAN(123). A PDP(Packet Data Protocol) context update request message which includes the bearer information is transmitted to the UP-GW(125). By responding to the PDP context update request message, a PDP context update response message indicating that a data tunnel for the UE is formed between the UP-GW and the RAN is received(127-135).

Description

Method of forming a data tunnel between a wireless access network and a user-end gateway in a wireless communication system and a system therefor {METHOD FOR ESTABLISHING DATA TUNNEL BETWEEN RAN AND USER PLANE GATEWAY IN WIRELESS TELECOMMUNICATIONS SYSTEM AND THEREFOR SYSTEM}

1 is a signaling flow diagram for forming a data tunnel between a radio access network (RAN) and a user-side gateway in accordance with a preferred embodiment of the present invention.

2 is a flowchart illustrating the operation of a control gateway (CP-GW) according to a preferred embodiment of the present invention.

3 is a flowchart illustrating the operation of a user-side gateway (UP-GW) according to a preferred embodiment of the present invention.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wireless communication system, and in particular, separates a network entity processing user data from a network entity processing a signaling message required for data transmission, and uses a network entity responsible for signaling to perform a network for data transmission. A method and system for forming a data tunnel between an entity and a Radio Access Network (RAN).

The third generation wireless communication system is developed from a typical second generation wireless communication system based on a voice service, and can support not only voice service but also relatively high-speed packet data service, and can be connected to a packet switched network. Most typical communication systems, including third generation wireless communication systems, have a structure in which one network entity has control protocols for processing signaling messages and user protocols for processing user data.

As a specific example, it is based on the European mobile communication system Global System for Mobile Communications (GSM) and General Packet Radio Services (GPRS), and uses Wideband Code Division Multiple Access (hereinafter referred to as CDMA). The UMTS (Universal Mobile Telecommunication Service) system, which is a third generation mobile communication system of the asynchronous type, includes a radio access network (RAN) and a core network (Core) capable of wirelessly connecting to a user equipment (UE). Data is transmitted to the UE using two tunnels, a data tunnel between a Serving GPRS Support Node (SGSN), which is a Network (CN) node, and a data tunnel between the SGSN and a Gateway GPRS Support Node (GGSN).

In the existing third generation system having such a structure, although SGSN does not perform any conversion or processing of user data at all, RAN and GGSN do not need to simply forward user data between RAN and GGSN. Separate tunnels must be formed in both directions between and. As such, managing two tunnels to RAN and GGSN for each UE for data forwarding for all UEs managed by SGSN is an unnecessary overhead for SGSN.

Accordingly, the present invention, which is designed to solve the problems of the prior art operating as described above, is a method and system for separating a network entity processing user data and a network entity processing signaling message required for data transmission in a wireless communication system. To provide.

The present invention provides a method and system for forming a data tunnel between a network entity responsible for data transmission and a radio access network (RAN) using a network entity responsible for signaling.

According to a preferred embodiment of the present invention, in a method for forming a data tunnel between a radio access network and a user-end gateway in a wireless communication system,

A paging request including bearer information of the user-end gateway for requesting packet data transmission to a user terminal in a control-end gateway that is distinguished from a user-end gateway that processes user data and processes a signaling message necessary for data transmission. Receiving the message,

Removing the bearer information from the paging request message and then broadcasting the page request message from which the bearer information has been removed to connectable all radio access networks (RANs);

Receiving a service request message corresponding to the paging request message from the user terminal through one RAN accessible to the user terminal among the RANs;

Establishing a radio access bearer (RAN) with the RAN in response to the service request message, and obtaining bearer information of the RAN from the RAN;

Transmitting a PDP context update request message including bearer information of the RAN to the user terminal;

And in response to the PDP context update request message, receiving a PDP context update response message indicating that a data tunnel is formed between the user terminal gateway and the RAN for the user terminal.

Another embodiment of the present invention provides a method of forming a data tunnel between a radio access network and a user-end gateway in a wireless communication system.

Receiving a packet data from the user terminal gateway, which is distinguished from the control terminal gateway that processes the signaling message necessary for data transmission, and receives the packet data to the user terminal;

Transmitting a paging request message including bearer information of the user end gateway to the control end gateway;

Receiving a PDP context update request message including bearer information of a radio access network (RAN) accessible to the user terminal from the control node gateway in response to the paging request message;

And forming a data tunnel with the RAN by using bearer information of the RAN, and transmitting a PDP context update response message corresponding to the PDP context update request message to the control node gateway. .

Hereinafter, with reference to the accompanying drawings will be described in detail the operating principle of the preferred embodiment of the present invention. In the following description of the present invention, detailed descriptions of well-known functions or configurations will be omitted if it is determined that the detailed description of the present invention may unnecessarily obscure the subject matter of the present invention. Terms to be described later are terms defined in consideration of functions in the present invention, and may be changed according to intentions or customs of users or operators. Therefore, the definition should be made based on the contents throughout the specification.

The main subject of the present invention to be described later is to separate a network entity processing user data from a network entity processing a signaling message required for data transmission in a wireless communication system, and is responsible for data transmission using a network entity responsible for signaling. A data tunnel is formed between a network entity and a radio access network (RAN).

In describing the present invention in detail, related terms and system architecture of an asynchronous wideband code division multiple access (WCDMA) system will be used. However, the main subject matter of the present invention can be applied to other mobile communication systems having a similar technical background and channel form with a slight modification without departing from the scope of the present invention. It will be possible at the judgment of those with knowledge.

In the present specification, a network entity processing a signaling message will be referred to as a control plane gateway (CP-GW), and a network entity processing user data will be referred to as a user plane gateway (UP-GW). will be. For example, in WCDMA, SGSN may be a control gateway that handles protocols of a control stage for processing signaling only, and GGSN may be a user-side gateway that handles user-side protocols in charge of processing user data. .

Hereinafter, specific operations for forming a data tunnel between a wireless access network (RAN) and a user-end gateway (UP-GW) that can be wirelessly connected to a terminal will be described.

1 is a signaling flow diagram for forming a data tunnel between a radio access network (RAN) and a user-side gateway according to a preferred embodiment of the present invention.

Referring to FIG. 1, when packet data for delivery to the UE 101 in an idle state is transmitted from the packet switched network to the UP-GW 107 in step 109, the UP-GW 109 in step 111. Transmits a paging request (PAGING REQUEST message) message through the CP-GW 105 to return the UE 101 in the IDLE state to the ACTIVE state. The PAGING REQUEST message message includes bearer information and the like for the UP-CP required to form a data tunnel between the UE 101 and the UP-GW 109. The bearer information includes the address (ie, GGSN IP) of the UP-GW 107 and identification information (ie, a tunnel endpoint identifier (TEID)) for the corresponding data tunnel. Since the PAGING REQUEST message is based on a protocol between the control gateway and the user gateway, its form and configuration will be determined based on the protocol.

The CP-GW 105 that receives the PAGING REQUEST message message from the UP-GW 107 stores the bearer information of the UP-GW 107 in step 113. As such, the bearer information of the UP-GW 107 is transmitted until the response to the PAGING REQUEST message message broadcasted from the CP-GW 105 to the RANs is transmitted from the specific RAN. Are stored in. As such, the bearer information of the UP-GW 107 is not transmitted to the RANs during the PAGING REQUEST message because the CP-GW 105 does not know which RAN the UE 101 in the IDLE state currently belongs to. to be. That is, since the bearer information of the UP-GW 107 is not transmitted to all RANs in the PAGING REQUEST message process, it is not necessary to transmit bearer information to the UE 101 as a dedicated, but is transmitted to all the RANs. Prevent signaling.

After storing the bearer information of the UP-GW 107, the CP-GW 105 broadcasts a PAGING REQUEST message message that does not include bearer information for the UP-GW 107 to all RANs in step 115. . In step 117, the RANs forward the PAGING REQUEST message message to all UEs managed by the RANs. The UE 101, which has confirmed that the PAGING REQUEST message is a message transmitted to itself among the UEs receiving the PAGING REQUEST message, in step 119, requests for service to restore the signaling connection with the CP-GW 105. REQUEST) message to the CP-GW 105.

The CP-GW 105 confirms the location of the UE 101 by receiving the SERVICE REQUEST message from the UE 101, and in step 123, the RAB (Radio Access) to the corresponding RAN 103 to which the UE 101 is connected. Bearer) Sends SETUP REQUEST message. The RAB SETUP REQUEST message is a quality of service for the packet data together with bearer information of the UP-GW 107 received by the CP-GW 105 through a PAGING REQUEST message message from the UP-GW 107. Service (QoS) related information. That is, bearer information for establishing a tunnel to the UP-GW 107 is transmitted to the RAN 103 through the RAQ SETUP REQUEST message.

After receiving the RAB SETUP REQUEST message from the CP-GW 105, in step 125, the RAN 103 sends an RB SETUP REQUEST message to the UE 101 to establish a wireless connection between the RAN 103 and the UE 101. In response, the UE 101 transmits an RB SETUP COMPLETE message to the RAN 103 in step 127. After the establishment of the radio connection between the terminal 101 and the RAN 103 is completed, in step 129, the RAN 103 sets its own address information (ie, RNC IP), tunnel identification information (TEID), etc. to establish the tunnel. Bearer information including the transfer to the CP-GW 105 through the RAB RESPONSE message.

After receiving the RAB RESPONSE message, in step 131, the CP-GW 105 updates the bearer information received from the RAN 103 through an UPDATE PDP CONTEXT REQUEST message. -To GW 107. The UP-GW 107 receives bearer information for tunnel formation with the RAN 103 through the UPDATE PDP CONTEXT REQUEST message, thereby completing information exchange between the RAN 103 and the UP-GW 107. In step 133, a tunnel for transmitting user data is formed. In addition, in step 135, the UP-GW 107 notifies the CP-GW 105 of the update of the PDP context of the UE 101 through an UPDATE PDP CONTEXT RESPONSE message.

Through the above process, tunnel formation for transmitting user data between the RAN 103 and the UP-GW 107 is completed, and the CP-GW 105 forms a tunnel between the RAN 103 and the UP-GW 107. It is only used to deliver control signaling for the system.

In a preferred embodiment of the present invention, the CP-GW is a network entity responsible for transmitting, processing, and generating control signaling between the RAN and the UP-GW and does not process user data delivered to the terminal. The CP-GW may be implemented as SGSN in the third generation system, and may be implemented as a control entity such as a mobility management entity (MME) in an extended system based on the third generation system. That is, the CP-GW is a network structure in which a network entity processing control signaling for a terminal and a network entity responsible for transmitting user data are functionally or physically separated. It refers to a network entity that is solely responsible for the processing of control signaling. In this specification, only functions necessary for processing signaling for supporting tunnel formation between the UP-GW and the RAN among the functions of the CP-GW will be described. However, the CP-GW will be able to handle other kinds of control signaling in addition to these functions.

2 is a flowchart illustrating the operation of a control stage gateway (CP-GW) according to a preferred embodiment of the present invention.

Referring to FIG. 2, at 201 the CP-GW is waiting to receive any message. When the PAGING REQUEST message message is received from the UP-GW to the CP-GW in step 203, the CP-GW recognizes that the packet data has been delivered to the UE requesting paging. In step 205, the CP-GW stores itself without forwarding bearer information about the UP-GW included in the PAGING REQUEST message message transmitted from the UP-GW to the RAN. This is to prevent unnecessary signaling overhead in which the bearer information of the UP-GW is forwarded to all the RANs belonging to the CP-GW since the CP-GW does not know the RAN accessible by the UE currently in the IDLE state. .

After storing the bearer information of the UP-GW, in step 207, the CP-GW generates a PAGING REQUEST message except for the bearer information of the UP-GW, and broadcasts the generated PAGING REQUEST message message to all RANs connected to the UP-GW. The PAGING REQUEST message delivered from the CP-GW to the RANs is delivered to the UE through the RAN connected to the UE, and the UE receiving the PAGING REQUEST message sends a SERVICE REQUEST message to the CP-GW to request connection establishment for data reception. It will be transmitted through the RAN.

In step 209, the CP-GW receives the SERVICE REQUEST message transmitted from the UE to determine the current location of the UE (i.e., the address of the RAN currently accessible by the UE). Send RAB SETUP REQUEST message requesting RAB setup. The RAB SETUP REQUEST message includes bearer information for the UP-GW necessary for establishing a tunnel with the UP-GW. After receiving the RAB SETUP REQUEST message, the RAN stores bearer information for the UP-GW, establishes a radio connection with the UE, and then transmits a RAB SETUP RESPONSE message to the CP-GW.

In step 213, the CP-GW receives the RAB SETUP RESPONSE message transmitted from the RAN. The RAB SETUP RESPONSE message includes bearer information of the RAN necessary for tunnel formation with the UP-GW. In step 215, the CP-GW transmits bearer information of the RAN to the UP-GW through an UPDATE PDP CONTEXT REQUEST message. In response to the UPDATE PDP CONTEXT REQUEST message, the UP-GW transmits an UPDATE PDP CONTEXT RESPONSE message to the CP-GW after completing the update of the PDP context related to the UE and the tunnel establishment with the RAN. In step 217, the CP-GW receives the UPDATE PDP CONTEXT RESPONSE message transmitted from the UP-GW, and completes the control message processing as a relay for forming a tunnel between the RAN and the UP-GW.

In a preferred embodiment of the present invention, the UP-GW is a network entity responsible for transmitting data for a terminal through a tunnel with the RAN. The UP-GW may be implemented as a GGSN in a third generation system, and may be implemented as one of all network entities that are responsible for transmitting user data, such as a user plane entity (UPE) in an extended system. have. In this specification, only functions for processing signaling with the CP-GW, obtaining bearer information of the RAN, and forming a tunnel with the RAN are described among the functions of the UP-GW in order to form a tunnel between the UP-GW and the RAN. However, the UP-GW can perform other kinds of functions besides these functions.

3 is a flowchart illustrating the operation of a user-side gateway (UP-GW) according to a preferred embodiment of the present invention.

Referring to FIG. 3, in step 301, the UP-GW waits for reception of user data for terminals. While waiting to receive the user data for the terminals, the UP-GW receives the user data for the specific terminal in step 303 and determines the current state of the terminal in step 305. If the terminal is in an ACTIVE state rather than in the IDLE state, the user data is transmitted through a data tunnel that is previously established between the RAN to which the terminal is connected. On the contrary, if the terminal is in the IDLE state, the UP-GW does not have information on the RAN providing the service for the terminal, and since the data tunnel necessary for data transmission with the RAN is not formed, step 307. Proceed to

In step 307, the UP-GW transmits a PAGING REQUEST message including its bearer information necessary for tunnel formation for the terminal to the CP-GW. The PAGING REQUEST message message, in addition to the purpose of transmitting the bearer information of the UP-GW to the RAN through the CP-GW, PAGING REQUEST (not including the bearer information of the UP-GW) to determine the current location of the terminal It has a function of triggering to broadcast a message to all RANs included in the routing area of the terminal by the CP-GW. The CP-GW identifies the RAN currently serving the UE in response to the PAGING REQUEST message, obtains bearer information for the RAN, updates the PDP context for the UE using the bearer information, In order to deliver bearer information of the RAN serving the UE to the UP-GW, an UPDATE PDP CONTEXT REQUEST message is transmitted to the UP-GW.

In step 309, the UP-GW receives the UPDATE PDP CONTEXT REQUEST message transmitted from the CP-GW. In step 311, the UP-GW updates the PDP context of the UE by using the RANDML bearer information included in the UPDATE PDP CONTEXT REQUEST message. And a tunnel necessary for data transmission of the UE. After updating the PDP context for the UE and forming the tunnel with the RAN, in step 313, the UP-GW transmits an UPDATE PDP CONTEXT RESPONSE message to the CP-GW, thereby performing tunnel formation with the RAN through the CP-GW. Complete the process.

Meanwhile, in the detailed description of the present invention, specific embodiments have been described, but various modifications are possible without departing from the scope of the present invention. Therefore, the scope of the present invention should not be limited to the described embodiments, but should be defined not only by the scope of the following claims, but also by those equivalent to the scope of the claims.

In the present invention operating as described in detail above, the effects obtained by the representative of the disclosed invention are briefly described as follows.

The present invention distinguishes a control-end gateway responsible for control signaling from a user-end gateway responsible for transmitting user data in a core network, and forms a direct data bearer, that is, a data tunnel, between a radio access network and a user-end gateway. The path between the terminal and the packet switched network can be simplified while reducing unnecessary signaling overhead for forming a data tunnel.

Claims (2)

A method of forming a data tunnel between a radio access network and a user-end gateway in a wireless communication system, A paging request including bearer information of the user-end gateway for requesting packet data transmission to a user terminal in a control-end gateway that is distinguished from a user-end gateway that processes user data and processes a signaling message necessary for data transmission. Receiving the message, Removing the bearer information from the paging request message and then broadcasting the page request message from which the bearer information has been removed to all connectable radio access networks (RANs); Receiving a service request message corresponding to the paging request message from the user terminal through one RAN accessible to the user terminal among the RANs; Establishing a radio access bearer (RAN) with the RAN in response to the service request message, and obtaining bearer information of the RAN from the RAN; Transmitting a PDP context update request message including bearer information of the RAN to the user terminal; Receiving a PDP context update response message indicating that a data tunnel for the user terminal is formed between the user-end gateway and the RAN in response to the PDP context update request message. . A method of forming a data tunnel between a radio access network and a user-end gateway in a wireless communication system, Receiving a packet data from the user terminal gateway, which is distinguished from the control terminal gateway that processes the signaling message necessary for data transmission, and receives the packet data to the user terminal; Transmitting a paging request message including bearer information of the user end gateway to the control end gateway; Receiving a PDP context update request message including bearer information of a radio access network (RAN) accessible to the user terminal from the control node gateway in response to the paging request message; Forming a data tunnel with the RAN by using bearer information of the RAN and transmitting a PDP context update response message corresponding to the PDP context update request message to the control node gateway; How to form a data tunnel.

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