KR101563491B1 - Apparatus for performing attach procedure in wireless communication system and method thereof - Google Patents

Abstract

The present invention relates to an apparatus and method for performing a connection procedure in a wireless communication system. The present invention assumes that a QoS profile is deleted in the SGW in a state where QoS is applied to a specific session. In this case, the service request of the UE is rejected, and a new connection procedure is performed. According to the embodiment of the present invention, the PGW does not interwork with the PCRF in the conventional case when the connection procedure is performed, but the PGW receives the new PCC rule in conjunction with the PCRF, QoS is applied. Therefore, it is not necessary to set the QoS for a new session to an entity on the network other than the SGW. And because the new QoS must be applied, no transaction will occur due to the procedure that occurs. Furthermore, since it is linked with the PCRF, the policy of the provider can be reflected as it is.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus and method for performing a connection procedure in a wireless communication system,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wireless communication technology, and more particularly, to a wireless communication system, Device and a method therefor.

In addition to LTE-A, LTE-A and Evolved High-Speed Packet Access (HSPA +), which are LTE-A (LTE advanced) . LTE is based on Release 8, a wireless high-speed data packet access standard established by the 3rd Generation Partnership Project (3GPP) in December 2008, and is aimed at 4G wireless technology (4G) designed to increase network capacity and speed. It is the technology of all stages. LTE is an all-IP-based network that provides differentiated QoS (Quality of Service) for real-time and non-real-time services and can provide efficiency of network resources and also introduces smart antenna technology (MIMO) It extends the bandwidth for wireless communications, supporting speeds up to 12 times faster than HSDPA. LTE-A is defined as improving the above-described LTE to provide a maximum transmission rate of 1 Gbps down and 500 Mbps upstream. This LTE-A provides higher data throughput than LTE through Carrier Aggregation (CA) and Coordinate Muti-Point (CoMP) technologies not supported by LTE. Here, CA is a technique of using frequency bands expanded by using different frequency bands at the same time, and CoMP is a technique for increasing throughput at a cell boundary through interference control by cooperation between neighboring base stations. Accordingly, in the current mobile communication system, two or more mobile communication services according to different standards such as LTE and LTE-Advanced are mixed and supported.

Korean Patent Laid-Open No. 10-2012-0126452, November 21, 2012 (Name: Mobile communication system for avoiding duplicated call processing and method for processing the call)

It is an object of the present invention to provide an apparatus and a method for performing an access procedure capable of reducing a transaction for connection when a duplicate access procedure is again generated due to deletion of a profile in a wireless communication system.

According to another aspect of the present invention, there is provided a packet gateway for performing a connection procedure, comprising: an interface for transmitting and receiving a message; A duplication determining unit for determining whether the received session creation request message is duplicated in the generated session upon receiving a session creation request message from the serving gateway through the interface unit; A rule processing unit for requesting a policy management server through the interface unit to receive a service quality profile for the session if the result of the determination is duplicated; And a rule application unit transmitting the session establishment response message including the received service quality profile to the serving gateway through the interface unit so that the serving gateway applies the received service quality profile to the session.

According to another aspect of the present invention, there is provided a method for performing a connection procedure of a packet gateway according to a preferred embodiment of the present invention. The method includes receiving a session creation request message, Judging whether or not it is determined to be an object; Requesting a policy management server to receive a service quality profile for the session if it is determined as a result of the determination; And transmitting a session establishment response message including the received quality of service profile to the serving gateway so that the quality of service for the session is set with the quality of service profile.

According to the present invention, even when the connection procedure related to the same session proceeds, the packet gateway receives the new PCC rule in cooperation with the policy management server, and applies the QoS to the session allocated through the QoS profile included in the PCC rule . Therefore, there is no need to set QoS for a new session of entities on the remaining networks except for the serving gateway. And because the new QoS must be applied, no transaction will occur due to the procedure that occurs. Therefore, the number of transactions is significantly reduced, and network resources can be saved. Furthermore, since it cooperates with the policy management server, the policy of the business operator can be reflected as it is.

1 is a diagram for explaining a schematic configuration of a wireless communication system according to an embodiment of the present invention.
2 is a block diagram illustrating a schematic internal structure of a packet gateway according to an embodiment of the present invention.
3 is a flowchart illustrating an initial connection procedure of a user apparatus according to an embodiment of the present invention.
4 is a flowchart illustrating a process of denial of service caused by deletion of a profile stored in the serving gateway.
5 is a flowchart illustrating a method for performing a connection procedure according to a conventional technique.
6 is a flowchart illustrating a method for performing a connection procedure according to an embodiment of the present invention.
7 is a flowchart illustrating a method for performing a connection procedure of a packet gateway according to an embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. Note that, in the drawings, the same components are denoted by the same reference symbols as possible. Further, the detailed description of known functions and configurations that may obscure the gist of the present invention will be omitted. For the same reason, some of the components in the drawings are exaggerated, omitted, or schematically illustrated.

1 is a diagram for explaining a schematic configuration of a wireless communication system according to an embodiment of the present invention.

1, a wireless communication system according to an embodiment of the present invention includes a base station (eNodeB, hereinafter referred to as "eNB") 100, a mobility management entity (hereinafter, referred to as "MME" (SGS) 300, a packet data network gateway (PGW) 400, a home subscriber server (HSS) 500, and a policy management server and Charging Rules Function (hereinafter, "PCRF ", 600).

The above-mentioned system is referred to as EPS (Evolved Packet System), and EPS is an EPC (Evolved Packet Core) which is an IP based packet switched core network and an Evolved Universal Terrestrial Radio Access Network (E-UTRAN) And a radio access network (RAN). Here, the EPC includes the MME 200, the SGW 300, the PGW 400, and the HSS 500.

Each of the entities according to the above-described embodiment of the present invention will be described.

The MME 200 includes an access to network connection, network resource allocation, tracking, paging, roaming and handover of a user equipment (UE) 10 It is an element that performs signaling and control functions to support. The MME 200 controls control plane functions related to subscriber and session management. The MME 200 manages a plurality of eNBs 100 and performs signaling for selection of a conventional gateway for handover to another 2G / 3G network. The MME 200 also performs functions such as security procedures, terminal-to-network session handling, and idle terminal location management.

The SGW 300 is an element that functions as a boundary point between a radio access network (RAN) and a core network and functions to maintain a data path between the eNB 100 and the PGW 400. [ In addition, when the UE 10 moves (e.g., handover, etc.) over an area served by the eNB 100, the SGW 300 may serve as an anchor point of the movement. That is, the packets can be routed through the SGW 300 for mobility in the E-UTRAN. In addition, the SGW 300 may be connected to another 3GPP network (RAN defined before 3GPP Release-8, e.g., UTRAN or GERAN (Enhanced Data Rates for Global Evolution) As shown in FIG.

The PGW 400 corresponds to the termination point of the data interface towards the packet data network. The PGW 400 may include policy enforcement features, packet filtering, charging support, lawful interception, UE IP allocation, packet screening, etc. (3GPP) network and a non-3GPP network (e.g., an untrusted network such as an Interworking Wireless Local Area Network (I-WLAN), a Code Division Multiple Access (CDMA) The same trusted network) as the anchor point for mobility management.

The HSS 500 manages subscription information (or subscription data or subscription records) and location information of the UE 10 (or a user).

The PCRF 600 manages a policy to be applied to the UE 10, a quality of service (QoS), and the like. The Policy and Charging Control (PCC) rule generated in the PCRF includes a QoS profile to be applied to a session (SIP message exchange or voice, data, and the like) providing a specific service and is transmitted to the PGW 400.

QoS applied according to the session (or bearer) is different and a QoS profile is transmitted to each entity on the network, i.e., the UE 10, the eNB 100, the MME 200, the SGW 300, And is applied to the QoS of the session. The QoS profile defines a priority, a guarantee bandwidth, an allowable bandwidth, a maximum bandwidth, whether a new bearer is created, and the like of a packet to be transmitted and received when a packet including data or a message is transmitted or received through the corresponding session. In the embodiment of the present invention, QoS means that each entity on the network, i.e., the UE 10, the eNB 100, the MME 200, the SGW 300 and the PGW 400, And transmits and receives packets according to a stored QoS profile when packets are transmitted and received through the session.

In the embodiment of the present invention, the QoS profile included in the PCC rule determined by the PCRF 600 will be referred to as an authenticated QoS profile. In addition, the session (or bearer) may be determined by the QoS profile included in the subscription information of the HSS 500. In the embodiment of the present invention, the QoS profile included in the subscription information of the HSS 500 will be referred to as a subscriber QoS profile.

When the UE 10 proceeds with the initial access procedure, a session is allocated, and each entity on the network applies QoS to the allocated session according to the authenticated QoS profile included in the PCC rule of the PCRF 600. The present invention assumes that the authentication QoS profile stored in the SGW 300 is deleted in this state. In this case, since the SGW 300 does not have a QoS profile for the session of the UE 10, the service request of the UE 10 will be rejected by the SGW 300. As a result, the UE 10 must proceed with a new connection procedure to proceed with the session creation procedure for the same session. At this time, according to the conventional technique, the PGW 400 does not interwork with the PCRF 600, the connection procedure proceeds, and the QoS for the session is applied by the subscription QoS profile of the HSS 500. [ Particularly, for QoS application, a PGW initiated QoS Modification (PGW initiated QoS Modification) by the PGW 400 is additionally performed. In the QoS modification procedure by the PGW 400, a large number of transactions occur, and the loss of network resources due to such transactions is large. Therefore, in order to reduce such a transaction, the present invention proceeds with a new initial access procedure in conjunction with the PCRF 600.

At this time, the PGW 400 requests the PCRF 600 to release the existing PCC rule, and releases the pre-allocated authentication QoS profile for the session. Then, the PGW 400 requests the PCRF 600 to generate the PCC rule again, and receives the authentication QoS profile according to the PCC rule newly generated from the PCRF 600. Since the received authentication QoS is the same as the authentication QoS profile stored in the PGW 400, the QoS application procedure is not performed in the new PGW 400. The PGW 400 transmits the authentication QoS profile received from the PCRF 600 to the SGW 300 so that the SGW 300 establishes a session based on the same authentication QoS as that of the PGW 400. [

2 is a block diagram illustrating a schematic internal structure of a packet gateway according to an embodiment of the present invention.

Referring to FIG. 2, the PGW 400 includes an interface unit 410, a storage unit 420, a duplication determination unit 430, a rule processing unit 440, and a rule application unit 450.

The interface unit 410 communicates with the SGW 300 and the PCRF 600 through different interfaces. For example, the interface unit 410 communicates with the SGW 300 through the S5 interface, and communicates with the PCRF 600 via the Gx interface.

The storage unit 420 is for storing data and may store various kinds of data according to an embodiment of the present invention. The storage unit 420 may store a connection profile for the UE 10. For example, the storage unit 220 may store an identifier of the UE 10, a session identifier assigned to the UE 10 and an authentication QoS profile applied to the session, a filtering rule applied to the session, a charging rule, . The storage unit 420 may include a part or all of the role of the Subscriber Profile Repository (SPR).

When the duplicate determination unit 430 receives a Create Session Request message from the SGW 300 through the interface unit 410, the duplication determination unit 430 determines whether the received session creation request message is duplicated for the created session . For example, if a session is already allocated through the initial access procedure of the UE 10 and PCC rules are applied to the session through the PCRF 600, all the entities on the network can transmit an authentication QoS profile Is applied. However, if the authentication QoS profile is deleted in the SGW 300, the service request of the UE 10 is rejected, and the UE 10 must proceed with the reconnection procedure again. In this case, the MME 200 transmits a session creation request message including the subscription QoS profile received from the HSS 500 to the SGW 300, and the SGW 300 also transmits a session creation request message including the subscription QoS profile To the PGW 400. However, in this case, since the authentication QoS profile stored in the storage unit 420 of the PGW 400 has not been deleted yet, it differs from the subscription QoS profile included in the session creation request message. In this case, the duplication determining unit 430 may determine that the session creation request message is duplicated.

If the duplicate determination unit 430 determines that the received session creation request message is duplicated for the generated session, the rule processing unit 440 determines whether the PCRF 600 is generated through the interface unit 410 And requests release of the PCC rule determined to be applied to the session. Then, the PCRF 600 will release the corresponding PCC rule. Accordingly, the authentication QoS profile for the created session is released as well. Then, the rule processing unit 440 requests the PCRF 600 to determine and provide PCC rules again for the session through the interface unit 410. Accordingly, the PCRF 600 will again determine and provide the PCC rules for the session. Accordingly, the rule processing unit 440 receives the PCC rules applied to the session. The received PCC rule includes an authentication QoS profile applied to the session. This authentication QoS profile is the same as that stored in the storage unit 420. [ Therefore, the rule application unit 450 does not change the authentication QoS profile stored in the storage unit 420. [

The rule application unit 450 transmits a session creation response message including the newly received authentication QoS profile to the SGW 300 through the interface unit 410. [ Then, the SGW 300 will apply the QoS of the session according to the authentication QoS profile of the PCRF 600.

3 is a flowchart illustrating an initial connection procedure of a user apparatus according to an embodiment of the present invention.

Referring to FIG. 3, when the UE 10 is turned on, the UE 10 starts an initial access procedure to access the mobile communication network for the first time. For initial connection, the UE 10 selects one of the plurality of eNBs 100 and establishes an RRC connection with the eNB 100 selected in step S110 (RRC Connection Establishment).

Next, in step S115, the UE 10 transmits an Attach Request message requesting an initial connection, and the connection request message is transmitted to the MME 200 via the eNB 100. [ The connection request message includes identification information and capability information of the UE 10. Here, the identification information may be an International Mobile Subscriber Identity (IMSI), a Globally Unique Temporary Identifier (GUTI), or an International Mobile Equipment Identity (IMEI), and may be an IMSI.

The MME 200 receiving the connection request message of the UE 10 proceeds with subscriber authentication and security setup for the UE 10 in step S120. The MME 200 obtains an authentication vector from the HSS 500 through the IMSI of the UE 10 and transmits a part of the authentication vector obtained from the HSS 500 to the UE 10 in step S120. . Then, the MME 200 and the UE 10 complete mutual authentication and security setting.

When the authentication and security setting procedure is completed, the MME 200 registers the UE 10 and confirms what services the UE 10 can use. To this end, the MME 200 must inform the HSS 500 that the UE 10 is connected to the MME 200 itself and is located in an area managed by the MME 200 itself. That is, the MME 200 transmits an Update Location Request message to the HSS 500 in step S125. The Update Location Request message includes an MME Identifier (MME ID) and a UE Identifier (IMSI).

The HSS 500 having received the Update Location Request message registers the location of the UE 10 in the MME 200 by mapping and storing the MME 200 identifier and the UE identifier.

The HSS 500 then extracts the subscription profile of the UE 10 and transmits an Update Location Answer message including the subscription information to the MME 200 in step S130. The subscription information is information related to a service to which a user (or UE) subscribes. If the UE 10 is subscribed to a service (e.g., LTE-A) according to the subscription information, it must allocate a network or radio resource to provide a quality of service (QoS) corresponding to the subscribed service. For example, the subscription information includes identification information (IMSI) of the UE 10, an APN (Subscribed APN) for the subscription service, identification information of the PGW 400 for accessing the APN A GW ID, a Subscribed QoS Profile (e.g., UE-AMBR, QCI, ARP, APN-AMBR (UL / DL), etc.). The MME 200 stores the subscription information received from the HSS 500 in the context of the UE 10.

After performing the location registration as described above, the MME 200 sets up the EPS session and the basic bearer using the subscription information, so that the UE 10 (user) can provide the subscribed quality of service (QoS) And radio resources. First, the MME 200 allocates an EPS Bearer ID (EBI) to the UE 10 to generate a basic bearer. Then, the MME 200 checks the APN received from the HSS 500 and decides which PGW 400 is to be connected to the corresponding APN. The PGW 400 decision can be made with the subscription information (P-GW ID) received from the HSS 500 or the PGW 400 through the DNS query. When the PGW 400 is selected, the SGW 300 is also selected.

The MME 200 transmits a Create Session Request message to the SGW 300 in step S135. The session creation request message includes the EPS bearer identifier (EBI) and the subscription information of the UE 10. In particular, the subscription information includes a subscription QoS profile.

The SGW 300 having received the session creation request message allocates a downlink S5 bearer identifier (S5 DL TEID). Then, in step S140, the SGW 300 transmits to the PGW 400 a session creation request message including a downlink S5 bearer identifier (S5 DL TEID).

When the PGW 400 receives the S5 DL TEID through the session creation request message, the downlink S5 bearer is set. Upon receiving the session creation request message, the PGW 400 recognizes that the UE 10 is a new user accessing the EPC and allocates an IP to be used when the UE 10 uses the APN.

Next, the PGW 400 transmits the subscription information of the UE 10 to the PCRF 600 and receives authorization for resource allocation according to the provider's policy. Accordingly, the PGW 400 transmits a CCR (Credit Control Request) message to the PCRF 600 in step S145. The Rule Assignment Request (CCR) message includes an identifier (e.g., Initiation) indicating that the session identifier and the new PCC rule are requested to request the application of the PCC rule for the corresponding EPS session. Here, the session identifier may be generated by combining the UE identifier and the bearer identifier. Since the PCC rules include an authenticated QoS profile, a rule assignment request (CCR) message may mean requesting an authenticated QoS profile.

In particular, the rule allocation request (CCR) message provides the PCRF 600 with the subscription information of the UE 10 received from the MME 200, and the PCRF 600 determines the PCC rules for applying the carrier policy do. As described above, the subscription information includes a subscription QoS profile. This subscription QoS profile is Quality of Service (QoS) applied to the bearer assigned to the UE 10.

The PCRF 600 refers to the Access Profile for the UE 10 to determine the PCC policy decision to the UE 10. [ In this embodiment, it is assumed that a Subscriber Profile Repository (SPR) is included in the PCRF 600 and is implemented. The SPR stores the Access Profile for the UE 10. Therefore, when the SPR is implemented in a device other than the PCRF 600, the PCRF 600 may request the SPR to obtain the connection profile. The connection profile includes SDF Filter, QCI, ARP, APN-AMBR (UL / DL), Charging Method, and Charging Reporting Action. Accordingly, the PCRF 600 determines the PCC rules by referring to the subscription information and the connection profile. At this time, the connection profile may have the same parameter as the subscription QoS profile, and in this case, the value of the parameter of the connection profile takes precedence over the value of the parameter of the subscription QoS profile. In an embodiment of the present invention, the fact that at least some of the subscription QoS profiles have been changed to values determined by the PCRF 600 is referred to as an authenticated QoS profile. The APN-AMBR (UL / DL) and the like can be exemplified by these parameters.

When the PCC rules are determined, the PCRF 600 maps and stores the determined PCC rules and an authentication QoS profile to be applied to the bearers of the UE 10 and the UE 10 to which the rules are applied, It is managed through an identifier. This is shown in Table 1, for example.

Session identifier PCC Rules UE identifier Bearer identifier Authentication QoS profile Session ID 1 SIP bearer IMSI 1 EBI = 5 QoS profile 1 Session ID 2 SIP bearer IMSI 4 EBI = 3 QoS Profile 3

The PCRF 600 transmits a credit control answer (CCA) message including the PCC rules to the PGW 400 in step S150. The PCC rules include an authenticated QoS profile. Here, the authentication QoS profile is a modification of the subscription QoS profile by the PCRF 600.

The PGW 400 that received the rule assignment response (CCA) message stores the PCC rules and applies them. That is, the PGW 400 must apply the authenticated QoS profile according to the PCC rule to the basic bearer and EPS session. To this end, the PGW 400 stores the authenticated QoS profile according to the PCC rules and delivers it to other entities on the network.

Accordingly, the PGW 400 transmits a Create Session Response message to the SGW 300 in step S155. The session creation response message includes an uplink S5 bearer identifier (S5 UL TEID) assigned by PGW 400. [ In addition, the session creation response message includes an authenticated QoS profile.

When the SGW 300 receives the session creation response message, the uplink S5 bearer is established according to the S5 UL TEID. Then, the SGW 300 allocates an uplink S1 bearer identifier (S1 UL TEID). Then, in step S160, the SGW 300 transmits a session establishment response message including an uplink S1 bearer identifier to the MME 200. [ Then, the uplink S1 bearer is set.

Upon receipt of the session creation response message, the MME 200 must transmit an Attach Accept message in response to the received Attach Request message (S115). This connection acknowledgment message is for informing that the connection request has been successfully made and will be transmitted to the UE 10 via the eNB 100. [ In addition, the MME 200 must deliver an authentication QoS profile.

Accordingly, the MME 200 transmits an Initial Context Setup Request message including an Attach Accept message to the eNB 100 in step S165. Here, the connection admission message includes information for setting the context of the UE 10, including the authentication QoS profile.

Meanwhile, the eNB 100 receiving the initial context setup request message allocates an identifier (DRB ID) of a data radio bearer (DRB) and sets the QoS of the DRB according to the authenticated QoS profile. Then, the eNB 100 transmits an RRC Connection Reconfiguration message to the UE 10 in step S170. Since the RRC connection is established when the UE 10 transmits an Attach Request message in advance, the RRC connection is now allowed to access and the parameter must be set again according to the resource allocated according to the specific service subscription information. Therefore, the RRC connection re- Connection Reconfiguration message to reconfigure the RRC connection. Therefore, the UE 10 reestablishes the RRC connection using the parameters received from the RRC connection re-establishment message. Then, an Attach Accept message is extracted from the RRC connection re-establishment message and an authentication QoS profile is applied.

As described above, the UE 10 having re-established the RRC connection transmits an RRC Connection Reconfiguration Complete message to the eNB 100 in response to the RRC Connection Reconfiguration message in step S175 do.

Meanwhile, in response to the context setup request message, the eNB 100 transmits an initial context setup response message to the MME 200 in step S180, and notifies that the connection is completed.

Meanwhile, in step S185, the UE 10 transmits an Attach Complete message in response to the ACK message to inform that the connection is completed. This connection completion message is transmitted to the MME 200 via the eNB 100. [

As described above, after the radio section between the UE 10 and the eNB 100 is re-established, the MME 200 establishes a bearer between the eNB 100 and the SGW 300. That is, the MME 200 transmits a Modify Bearer Request message to the SGW 300 in step S190, and the SGW 300 transmits a Modify Bearer Response message in step S195 To the MME 200, whereby the S1 bearer connection between the eNB 100 and the SGW 300 is established. Accordingly, the eNB 100 and the SGW 300 can transmit traffic to each other.

4 is a flowchart illustrating a process of denial of service caused by deletion of a profile stored in the serving gateway.

Referring to FIG. 4, it is assumed that the authentication QoS profile of the SGW 300 is deleted in step S210. For example, the profile for the user including the authenticated QoS profile may be deleted by the long call delete function because there is no traffic for a long time.

When the UE 10 initially accesses and registers the network with the authentication QoS profile of the SGW 300 deleted, if there is no traffic, it becomes idle (IDLE) and the S1 connection can be released. In this idle state, the UE 10 starts a service request procedure in which new traffic is generated and the service is requested again to the network.

For the service request, the UE 10 transmits a service request message in step S220. This Service Request message is transmitted to the MME 200 through the eNB 100. Then, the MME 200 transmits a Modify Bearer Request message to the SGW 300 in step S230.

The SGW 300 does not transmit a Modify Bearer Request message to the PGW 400 because the authentication QoS profile has been deleted. Instead, the SGW 300 transmits a Modify Bearer Response message for rejecting the bearer modification request to the MME 200 in step S240. Then, in step S250, the MME 200 transmits a Service Response message to the UE 10 to reject the service request.

As described above, if the service request is rejected, the UE 10 has to go through the connection procedure again. 5 and 6, a connection procedure according to a conventional technique and a connection procedure according to an embodiment of the present invention will be compared.

5 is a flowchart illustrating a method for performing a connection procedure according to a conventional technique. The conventional technique of FIG. 5 occurs when the service request procedure is rejected due to deletion of the authentication QoS profile of the SGW 300 as described in FIG.

Referring to FIG. 5, if the service request is rejected, the UE 10 forwards an attach request message to the MME 200 in step S300. In step S305, the MME 200 transmits a Create Session Request message including the subscription QoS profile to the SGW 300. In step S310, the SGW 300 transmits a session creation request message including the subscription QoS profile to the PGW 400. [ Since the PGW 400 has received the same session, that is, the generation request for the created session, it does not work with the PCRF 600. When the PGW 400 receives the session creation request message from the SGW 300, the PGW 400 stores the subscription QoS profile of the received session creation request message.

Next, the PGW 400 transmits a Create Bearer Response message to the SGW 300 in step S315, and the SGW 300 transmits a session creation response message to the MME 200 in step S320.

The MME 200 transmits an Initial Context Setup Request including an Attach Accept message to the eNB 100 in step S325. the eNB 100 transmits an RRC Connection Reconfiguration (RRC Connection Reconfiguration) message including a connection acceptance message to the UE 10 in step S330.

In response to the RRC connection re-establishment message, the UE 10 transmits an RRC Connection Reconfiguration Complete message to the eNB 100 in step S335. Then, the eNB 100 transmits an Initial Context Setup Response message to the MME 200 in step S340.

Meanwhile, in step S345, the UE 10 transmits an Attach Complete message in response to an Attach Accept message to notify that the connection is completed. Here, the connection completion message is transmitted from the UE 10 to the eNB 100 through a direct transfer process, and the eNB 100 transmits a connection completion message to the MME 200.

On the other hand, the PGW 400 further proceeds with the following PGW initiated QoS Modification (PGW) by the PGW 400 to modify the QoS to the subscription QoS profile. That is, the PGW 400 transmits an Update Bearer Request message to the SGW 300 in step S350. The Update Bearer Request message includes a QoS profile, which is a subscription QoS profile of the HSS 500.

The SGW 300 forwards the bearer update request message to the MME 200 in step S355. The MME 200 transmits a Bearer Modify Request message including a Session Management Request message to the eNB 100 in step S360. In step S365, the eNB 100 transmits an RRC Connection Reconfiguration message including a Session Management Request message to the UE 10. [

The UE 10 transmits an RRC connection reset completion message to the eNB 100 in step S370. Then, the eNB 100 transmits a Bearer Modify Response message to the MME 200 in step S375. In step S380, the UE 10 transmits a Session Management Response message to the eNB 100 through a direct transfer process. In step S385, the eNB 100 transmits a session management response Management Response) message to the MME 200.

The MME 200 transmits an Update Bearer Response message to the SGW 300 in step S390 and the SGW 300 transmits an Update Bearer Response message to the PGW 400 ). This completes the bearer update procedure.

As shown, the connection procedure and the bearer update procedure according to the related art as described above cause a large number of transactions, which can result in loss of network resources. In addition, since the QoS according to the PCC rules of the PCRF 600 is not applied and the QoS of the HSS 500 is applied, the policy of the provider may not be properly reflected.

Therefore, the embodiment of the present invention proceeds with the connection procedure in conjunction with the PCRF 600. 6 is a flowchart illustrating a method for performing a connection procedure according to an embodiment of the present invention. The connection procedure described in FIG. 6 is performed when the service request is rejected due to the deletion of the QoS profile of the SGW 300 as described above with reference to FIG.

Referring to FIG. 6, the UE 10 transmits an Attach Request message to the MME 200 in step S410. Accordingly, the MME 200 transmits a Create Session Request message to the SGW 300 in step S415. At this time, the session creation request message transmitted from the MME 200 includes the subscription information received from the HSS 500. In particular, the subscription information includes a subscription QoS profile. Then, the SGW 300 transmits a session creation request message to the PGW 400 in step S420.

The PGW 400 receives the CCA message from the PCRF 600 in step S150 of FIG. 3 and stores the authentication QoS profile according to the PCC rule. Accordingly, when the PGW 400 receives the subscription QoS profile of the UE 10 through the session creation request message, it can recognize that the PGW 400 is different from the authentication QoS profile of the previously stored UE 10. Then, the following procedure is performed according to the embodiment of the present invention.

In step S425, the PGW 400 transmits a CCR (Credit Control Request) message to the PCRF 600 requesting to release the pre-assigned PCC rule for the session. The rule release request message may include a session identifier (e.g., Session ID 1 in Table 1) and a release indicator (e.g., Termination) to indicate requesting a PCC rule release that is mapped to a particular session. This CCR (Credit Control Request) message is the same as requesting to release the authentication QoS profile for a particular session.

When the PCRF 600 receives the rule release request (CCR) message, the PCRF 600 releases the PCC rule mapped to the session identifier. Accordingly, the authentication QoS profile for the session is released. In step S430, the PCRF 600 transmits a Credit Control Answer (CCA) message to the PGW 400 indicating that the PCC is released. The rule release response message may include a session identifier (e.g., Session ID 1 in Table 1) and a release indicator (e.g., Termination) to indicate that the PCC rule mapped to a particular session is released.

The PGW 400 having received the rule release response (CCA) message transmits a CCR (Credit Control Request) message requesting the allocation of the PCC rule to the PGW 400 in step S435. The Rule Assignment Request (CCR) message includes an indication (e. G., An Initiation) indicating that it is requesting a PCC rule and a session identifier for identifying a particular session to request a PCC rule applied for that particular session. This rule assignment request (CCR) message is equivalent to requesting an authentication QoS profile for a particular session.

The rule allocation request (CCR) message provides the subscription information including the subscription QoS profile of the UE 10 received from the MME 200 to the PCRF 600, and the PCRF 600 applies the provider policy Determine the PCC rules. When the PCRF 600 receives the rule allocation request (CCR) message, the PCRF 600 determines the PCC rule again for the session to be allocated to the UE 10. At this time, the PCRF 600 refers to the access profile for the UE 10 to determine the PCC policy decision to the UE 10. The connection profile includes SDF Filter, QCI, ARP, APN-AMBR (UL / DL), Charging Method, and Charging Reporting Action.

When the PCRF 600 determines the PCC rule, the value of the connection profile is prior to the value of the subscription QoS profile of the subscription information for the same parameter as the subscription QoS profile. The APN-AMBR (UL / DL) and the like can be exemplified by these parameters. Therefore, when generating the PCC rule, the PCRF 600 generates an authenticated QoS profile in which the subscription QoS profile is modified according to the service profile. Then, in step S440, the PCRF 600 transmits a CRC (Credit Control Answer) message including the PCC rule to the PGW 400. In particular, the PCC rules include an authenticated QoS profile. This rule assignment response (CCA) message includes a session identifier for identifying a particular session and an indicator (e.g., Initiation) indicating that the PCC rule is provided to indicate that it provides the PCC rules that apply for a particular session.

Upon receiving the rule assignment response (CCA) message, the PGW (400) must apply the authenticated QoS profile according to the PCC rules to the corresponding session. However, since the PGW 400 stores the same authentication QoS profile as the received QoS profile received through the rule assignment response (CCA) message, the QoS setting procedure in the PGW 400 is not performed. Instead, the PGW 400 must deliver the newly assigned authenticated QoS profile to other entities on the network. The following procedure for delivering an authenticated QoS profile to other entities on the network proceeds in the same manner as the initial access procedure of FIG.

That is, the PGW 400 transmits a Create Session Response message including the authentication QoS profile to the SGW 300 in step S445. Then, the SGW 300 newly stores the authentication QoS profile. In step S450, the SGW 300 transmits a Create Session Response message to the MME 200, and an authenticated QoS profile is transmitted thereto. Other network entities may not have the QoS establishment procedure because the authentication QoS profile has not been deleted. The MME 200 transmits an Initial Context Setup Request including an Attach Accept message in step S455, and the authentication QoS profile is transmitted through the Initial Context Setup Request.

the eNB 100 transmits an RRC Connection Reconfiguration message to the UE 10 in step S460. The RRC Connection Reconfiguration message includes a Connection Accept message and an Authentication QoS profile is delivered via an Attach Accept message.

In response to the RRC connection re-establishment message, the UE 10 transmits an RRC Connection Reconfiguration Complete message to the eNB 100 in step S465. Then, in step S470, the eNB 100 transmits an Initial Context Setup Response message to the MME 200 to inform that the connection is completed.

Meanwhile, in step S475, the UE 10 transmits an Attach Complete message in response to an Attach Accept message to notify that the connection is completed. This connection completion message is transmitted to the MME 200 via the eNB 100. [

The MME 200 transmits a Modify Bearer Request message to the SGW 300 in step S480 and the SGW 300 transmits a Modify Bearer Response message in step S485, By transmitting a message to the MME 200, an S1 bearer connection between the eNB 100 and the SGW 300 is established. Accordingly, the eNB 100 and the SGW 300 can transmit traffic to each other.

5 and 6, the conventional technique and the present invention have been compared and described. As shown, the prior art applies a subscription QoS profile in bearer setup, whereas the present invention applies an authenticated QoS profile. Therefore, the entities on the remaining networks except the SGW 300 do not need to re-establish the QoS for the session.

In particular, the conventional technique should further perform the PGW initiated QoS Modification by the PGW 400 as in steps S350 to S395 of FIG. However, the present invention does not have such an additional procedure, thereby reducing the number of transactions. That is, 20 transactions (steps S300 to S395) occur in FIG. 5, and 16 transactions (steps S410 to S485) occur, so that the present invention can reduce 4 transactions have. This is merely the difference in the number of transactions occurring in the process of one UE 10, and the transaction will be significantly reduced when considering the processes of the UEs 10 of all subscribers subscribed to the mobile communication service. Accordingly, according to the present invention, traffic in the EPC is significantly reduced, thereby saving network resources.

7 is a flowchart illustrating a method for performing a connection procedure of a packet gateway according to an embodiment of the present invention.

The UE 10 proceeds to the initial access procedure and is allocated a session and each entity on the network, i.e., the UE 10, the eNB 100, the MME 200, the SGW 300 and the PGW 400, It is assumed that the QoS applied to the session is applied according to the authentication QoS profile included in the PCC rule of FIG. That is, the QoS profile applied to the session allocated to the UE 10 in the initial access procedure is stored in the storage unit 420 of the PGW 400, and the QoS profile is included in the PCC rule from the PCRF 600 Received authentication QoS profile.

The duplication determination unit 430 of the PGW 400 may receive a session creation request message requesting the session creation from the SGW 300 through the interface unit 410 in step S510. Then, in step S515, the duplication determining unit 430 determines whether the session creation request message is duplicated for one session.

It is assumed that the QoS profile is deleted in the SGW 300 before the SGW 300 transmits a session creation request message. It is also assumed that the UE 10 has started the service request procedure through the allocated session in the initial access procedure. Then, the SGW 300 will reject the procedure because the QoS profile has been deleted. Then, the UE 10 proceeds the connection procedure again. If the reconnection procedure proceeds, the MME 200 will send a session creation request message containing the subscription QoS profile received from the HSS 500 to the SGW 300. Accordingly, the SGW 300 will also send a session creation request message including the subscription QoS profile to the PGW 400. When the interface generation unit 410 of the PGW 400 receives the session creation request message, the QoS profile for the corresponding session stored in the storage unit 420 of the PGW 400 is an authenticated QoS profile, The embedded QoS profile is a subscription QoS profile. In this case, the duplication determining unit 430 may determine that the session creation request message is duplicated.

On the other hand, in the general case, since the session creation request is to newly establish a session, the QoS for the session is not stored. In this case, the duplication determining unit 430 determines that the session creation request message is not duplicated.

As a result of the determination in step S515, if the received session creation request message is duplicated for one session, the rule processing unit 440 transmits a rule release request (CCR) request for releasing the applied PCC rule for the session in step S520, And transmits a Credit Control Request message to the PCRF 600 through the interface unit 410. Since the PCC rule includes an authenticated QoS profile, the rule release request message requests release of the pre-assigned authenticated QoS profile for the session.

When the PCRF 600 receives the rule release request (CCR) message, the PCRF 600 releases the pre-assigned PCC rule for the session. Accordingly, the authentication QoS profile for the session is also released. The PCRF 600 will then send a Rule Release Response (CCA) message to the PGW 400 indicating that the PCC rule has been released. The rule processing unit 440 receives a rule release response (CCA) message through the interface unit 410 in step S525. Then, the rule processing unit 440 can recognize that the authentication QoS profile is released together with the PCC rule for the session.

In step S530, the rule processing unit 440 transmits a rule allocation request (CCR) message requesting the PCC rule to the PGW 400 through the interface unit 410. [ A rule assignment request (CCR) message means requesting an authentication QoS profile along with PCC rules.

The Rule Assignment Request (CCR) message provides the PCRF 600 with the UE 10 subscription information received from the MME 200 and allows the PCRF 600 to determine the PCC rules to which the provider policy applies. That is, upon receiving the rule allocation request (CCR) message, the PCRF 600 refers to the connection profile for the session to be allocated to the UE 10 and determines the PCC rule again. At this time, the PCRF 600 generates an authenticated QoS profile modified according to the service profile of the subscription QoS profile, and the determined PCC rule includes this authenticated QoS profile. Then, the PCRF 600 transmits a rule assignment response (CCA) message containing the determined PCC rule to the PGW 400. [

The rule processing unit 440 receives the rule assignment response message through the interface unit 410 in step S535. The rule processing unit 440 does not set the QoS because the authentication QoS profile included in the rule assignment response message is the same as that stored previously. Instead, the rule application unit 450 transmits a Create Session Response message including an authenticated QoS profile so that the SGW 300 applies the authenticated QoS profile to the session in step S540. When the PCC rule including the authentication QoS profile is transmitted to the SGW 300 through the session creation response message, the SGW 300 applies the received authentication QoS profile to the corresponding session.

In step S515, the rule processing unit 440 transmits a rule allocation request (CCR) message to the PGW 400 through the interface unit 410 in step S545. The PCRF 600 then generates a PCC rule that includes an authenticated QoS profile that modifies the subscription QoS profile according to the service profile and sends a rule assignment response (CCA) message to the PGW 400 that includes the determined PCC rule . Then, the rule processing unit 440 receives a rule assignment response (CCA) message through the interface unit 410 in step S550. In step S555, the rule application unit 450 stores the PCC rule including the authentication QoS profile in the storage unit 420 so that the authentication QoS profile of the rule assignment response message is applied to the session.

Next, in step S560, the rule application unit 450 transmits a Create Session Response message so that the SGW 300 applies the authenticated QoS profile to the session. The PCC rule including the authentication QoS profile is transmitted to the SGW 300 through the session creation response message.

The apparatus and method for performing the connection procedure in the wireless communication system according to the embodiment of the present invention may be provided in the form of a computer readable medium suitable for storing computer program instructions and data. At this time, a computer-readable medium suitable for storing computer program instructions and data includes, for example, a magnetic medium such as a hard disk, a floppy disk and a magnetic tape, a compact disk read only memory (CD-ROM) Optical media such as a DVD (Digital Video Disk), a magneto-optical medium such as a floppy disk, and a ROM (Read Only Memory), a RAM , Random Access Memory), flash memory, EPROM (Erasable Programmable ROM), and EEPROM (Electrically Erasable Programmable ROM). The processor and memory may be supplemented by, or incorporated in, special purpose logic circuits. Examples of program instructions may include machine language code such as those generated by a compiler, as well as high-level language code that may be executed by a computer using an interpreter or the like. Such a hardware device may be configured to operate as one or more software modules to perform the operations of the present invention, and vice versa.

While the specification contains a number of specific implementation details, it should be understood that they are not to be construed as limitations on the scope of any invention or claim, but rather on the description of features that may be specific to a particular embodiment of a particular invention Should be understood. Certain features described herein in the context of separate embodiments may be implemented in combination in a single embodiment. Conversely, various features described in the context of a single embodiment may also be implemented in multiple embodiments, either individually or in any suitable subcombination. Further, although the features may operate in a particular combination and may be initially described as so claimed, one or more features from the claimed combination may in some cases be excluded from the combination, Or a variant of a subcombination.

Likewise, although the operations are depicted in the drawings in a particular order, it should be understood that such operations must be performed in that particular order or sequential order shown to achieve the desired result, or that all illustrated operations should be performed. In certain cases, multitasking and parallel processing may be advantageous. Also, the separation of the various system components of the above-described embodiments should not be understood as requiring such separation in all embodiments, and the described program components and systems will generally be integrated together into a single software product or packaged into multiple software products It should be understood.

It should be noted that the embodiments of the present invention disclosed in the present specification and drawings are only illustrative of specific examples for the purpose of understanding and are not intended to limit the scope of the present invention. It will be apparent to those skilled in the art that other modifications based on the technical idea of the present invention are possible in addition to the embodiments disclosed herein.

The present invention relates to an apparatus and method for performing a connection procedure in a wireless communication system. The present invention assumes that a QoS profile is deleted in the SGW in a state where QoS is applied to a specific session. In this case, the service request of the UE is rejected, and a new connection procedure is performed. According to the embodiment of the present invention, the PGW does not interwork with the PCRF in the conventional case when the connection procedure is performed, but the PGW receives the new PCC rule in conjunction with the PCRF, QoS is applied. Therefore, entities on the remaining networks except the SGW do not need to reconfigure QoS for the session. And because the new QoS must be applied, no transaction will occur due to the procedure that occurs. Furthermore, since it is linked with the PCRF, the policy of the provider can be reflected as it is. This is not only a possibility of commercialization or sales, but also a possibility of being industrially applicable since it is practically possible to carry out clearly.

100: base station, eNB 200: mobility management server, MME
300: Serving gateway, SGW 400: Packet gateway, PGW
410: interface unit 420: storage unit
430: duplication determination unit 440: rule processing unit
450: rule application unit 500: home subscriber server, HSS
600: Policy management server, PCRF

Claims (7)

An interface unit for transmitting and receiving a message;
A duplication determining unit for determining whether the received session creation request message is duplicated in the generated session upon receiving a session creation request message from the serving gateway through the interface unit;
If it is determined as a result of the determination, it transmits a rule allocation request message for requesting a service quality profile to the policy management server through the interface unit, and transmits a rule- A processor; And
And a rule application unit for transmitting a session establishment response message including the received service quality profile to the serving gateway through the interface unit. delete The method according to claim 1,
The rule processing unit
And transmits a rule release request message to the policy management server through the interface unit such that a pre-allocated quality of service profile for the session is released before transmitting the rule allocation request message. Gateway. The method according to claim 1,
The duplication determining unit
Wherein the packet gateway determines that the session creation request message is duplicated when a service quality profile different from the service quality profile for the session is received through the session creation request message. Upon receiving a session creation request message from the serving gateway, determining whether the session creation request message is duplicated in the created session;
Transmitting a rule allocation request message requesting a service quality profile to the policy management server if the determination result is duplicated;
Receiving a service quality profile for the session through a rule assignment response message, which is a response to the rule assignment request message, from the policy management server; And
And sending a session creation response message including the received quality of service profile to a serving gateway. ≪ Desc / Clms Page number 19 > delete 6. The method of claim 5,
Before transmitting the rule allocation request message,
And transmitting a rule release request message to the policy management server so that the pre-assigned QoS profile for the session is released.

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