WO2009105941A1

WO2009105941A1 - Method for ensuring continuity of quality of service in a resource and admission control system

Info

Publication number: WO2009105941A1
Application number: PCT/CN2008/070805
Authority: WO
Inventors: 兰光华; 宋军
Original assignee: 中兴通讯股份有限公司
Priority date: 2008-02-25
Filing date: 2008-04-25
Publication date: 2009-09-03
Also published as: CN101232733A; CN101232733B

Abstract

A method for ensuring continuity of Quality of Service in a Resource and Admission Control System, the method includes the steps of that: when a terminal user moves from a transport layer entity to another transport layer entity, after the current transport layer entity has completed the link layer mobility switching (403) operation, the link layer mobility event of the terminal user is notified to the Resource and Admission Control System to which the terminal user belongs. The Resource and Admission Control System judges whether the terminal user moves in a control range of the same Resource and Admission Control System, if it is yes, the reserved resource of the terminal user is searched in a database itself, and the resource is reserved on the current transport layer entity according to the resource reserved. Using the invention, in the next generation network, when the terminal user moves among different transport layer entities under the control of the same Resource and Admission Control System, the continuity of Quality of Service should be ensured.

Description

Method for guaranteeing continuity of service quality in resource admission control system

Technical field

The present invention relates to the field of communications, and in particular, to a method for guaranteeing continuity of service quality in a resource admission control system.

Background technique

NGN network (Next Generation Network) Because the bearer network uses packet technology, especially IP technology, its QoS (Quality of Service) problem is particularly prominent.

The ITU-T (International Telecommunication Union Telecommunication Standardization Sector) and the ETSI (European Telecommunications Standards Institute) have established dedicated research groups dedicated to the development of NGN technical standards. They propose RACF (Resource and Admission Control Function) (ITU-T) and RACS (Resource and Admission Control Subsystem) (ETSI) to solve the QoS problem of the NGN bearer network.

Although the drafts of the resource admission control systems of the two organizations are different and some specific functional entity definitions are slightly different, the framework is similar and compatible. That is, based on the operation policy rules, admission control and resource reservation are performed according to the user's subscription QoS information and available resources within the network. In the present invention, RACF and RACS are collectively referred to as a resource admission control system.

The functional framework of RACF is shown in Figure 1, in which:

PD-FE (Policy Decision Function Entity) is a policy decision function entity that makes preliminary QoS resource decisions based on media stream session information and user's transmission resource subscription information, and then transmits with TRC-FE (Transport Resource Control Function Entity: The resource control function entity) interacts to confirm whether there are enough QoS resources, and finally makes a final decision, and sends the decision to the PE-FE (Policy Execute Function Entity). The PD-FE obtains the media stream from the SCF (Service Control Function) through the Rs interface.

1 180800442 The session information is obtained from the NACF (Network Attachment Control Function) of the user through the Ru interface.

TRC-FE is mainly responsible for resource control, monitoring resources in the network and collecting relevant information. When PD-FE requests resources, it responds according to the specific resource status.

The transport layer entity completes the transmission of the service flow under the control of the RACF, mainly including PE-FE and

TRE-FE (Transport Resource Execute Function Entity) Functional entity, etc.

PE-FE mainly performs policy control (gating, bandwidth, traffic classification and labeling, traffic shaping, Layer 2 and Layer 3 QoS mapping, collecting and reporting resource usage information, etc.) under the guidance of PD-FE.

TRE-FE mainly performs Layer 2 policy enforcement under the guidance of TRC-FE, but the specific functions and scope are not determined.

NACF mainly completes the management of user attachment to the access network. The main functions include: dynamically providing IP addresses for user equipment and other network configuration parameters; authenticating the access layer for users; based on user service list, User authorization for network access; configuration of access network based on user service list; management of user location information.

Mobility refers to the ability to continuously access services and continue communication for changes in user and terminal locations. Mobility management refers to the problems involved in user mobility in mobile communication networks, including location management, handover management, and the like. Mobility management is a core issue in mobile communication networks. According to the hierarchical structure of the IP network, the mobility management of the all-IP mobile communication network can be divided into air interface (physical layer) mobile handover management, link layer mobility handover management, network layer mobility handover management, transport layer mobility handover management, and application layer mobility. Switch management 5 levels.

In the actual operation and deployment, in order to ensure the user's service experience during the mobile process, it is necessary to ensure that the mobile user can obtain sufficient resources and service quality assurance in the new network environment. How to ensure the continuous availability of resources is the core issue facing the current resource admission control system. In the current RACF architecture, there is no function to guarantee the quality of service in the process of end-user mobility. A user mobility scenario is proposed only in the specification document. In this scenario, the terminal user triggers the service system to perform handover management through the signaling, which belongs to the application layer mobility management category, and the RACF itself does not perceive the mobility of the terminal user.

2 180800442 Summary of the invention

The technical problem to be solved by the present invention is to provide a method for guaranteeing continuity of service quality in a resource admission control system, which can ensure continuity of service quality when an end user moves between different transport layer entities under the control of the same resource admission control system. .

In order to solve the above problem, the present invention provides a method for guaranteeing continuity of service quality in a resource admission control system, including: when a terminal user moves from one transport layer entity to another transport layer entity, the current transport layer entity completes the link. Notifying the link layer mobility event of the terminal user to the associated resource admission control system after the layer mobility switching operation;

The resource admission control system determines whether the terminal user moves within the control range of the same resource admission control system, and if so, retrieves the resource reservation of the terminal user in its own database, and reserves the resource according to the resource reservation. The current transport layer entity reserves resources.

Further, the current transport layer entity carries the auxiliary information when the link layer mobility event of the terminal user is notified to the resource access control system, and the auxiliary information includes the terminal user identifier, the previous transport layer entity identifier, and the service control function. One or any combination of entity location information and network attachment control function entity location information.

Further, the auxiliary information includes an end user identifier, and the resource admission control system determines, according to the terminal user identifier, whether the terminal user identifier is stored locally, and if yes, the terminal user is controlled by the same resource admission control system. Move within range.

Further, the auxiliary information includes a previous transport layer entity identifier, and the resource admission control system determines whether the previous transport layer entity identifier belongs to its own control range. If yes, the terminal user is in the same resource admission control system. Move within the control range.

Further, the method for the resource admission control system to reserve resources on the current transport layer entity according to the resource reservation of the terminal user is: the resource admission control system reserves the reservation stored in the database on the current transport layer entity. Resources with equal resources. Further, when the terminal user moves within the control range of the same resource admission control system, the resource admission control system further retrieves the policy of the terminal user in its own database.

3 180800442 Further, the resource admission control system further acquires the service statistics information of the terminal user from the previous transport layer entity according to the user identifier or the policy identifier information, and then sends the service statistics information to the current transport layer entity in whole or in part.

Further, when the service statistics information is obtained from the previous transport layer entity, only the service statistics related to the current service are obtained, and the service statistics related to the current service are sent to the current transport layer entity.

Further, the resource admission control system switches the service of the terminal user to the current transport layer entity after the terminal user reserves resources on the current transport layer entity.

Further, after the service of the terminal user is switched to the current transport layer entity, the resource admission control system releases the resources allocated to the terminal user on the previous transport layer entity and the installed policy.

In the NGN network, when the end user moves between different transport layer entities under the same resource admission control system, the resource admission control system can notify the link layer mobility event from the current transport layer. Knowing the resource reservation of the terminal user in the previous transport layer entity, and reserving resources on the current transport layer entity according to the resource reservation condition, ensuring that sufficient resources are reserved before the end user's service completes the handover, thereby ensuring The continuity of business service quality. BRIEF abstract

1 is an architectural diagram of a resource admission control function RACF of the ITU-T in the prior art; FIG. 2 is a mobile scenario in a WLAN environment according to the present invention;

3 is a schematic diagram of movement of a mobile user under RACF in the present invention;

4 is a flowchart of a link layer mobility handover triggering RACF resource update in the present invention. Preferred embodiment of the invention

The technical solution of the present invention will be described in detail below with reference to the accompanying drawings.

The invention adopts a wireless local area network WLAN (Wireless Local Area Network)

4 180800442 For the sake of example, a preferred embodiment is given.

Figure 2 is a schematic diagram of a mobile node moving in a WLAN environment. In a WLAN environment, a mobile node communicates with a WLAN access point (AP: Access Point) over an IEEE 802.11 a/b/g air interface. The access controller (AC: Access Controller) can manage multiple APs, and the AP and AC communicate with each other through a wired network (xDSL, LAN, etc.). The Remote Broadband Access Server (BRAS: Bandwidth Remote Access Server) provides functions such as authentication, authorization, and accounting for remote access terminal users. The AC is usually connected to the BRAS through an aggregation network (ether, ATM, etc.). The Resource Admission Control System (RACF) performs admission control on user-initiated service requests, and performs resource reservation on the AC, aggregation network, and BRAS to ensure service quality of the service.

In Figure 2, AC1 controls the API and AP2, and AC2 controls AP3. AC1 and AC2 access the BRAS through the aggregation network. The RACF can reserve transmission resources on entities such as AC 1, AC 2, aggregation network, and BRAS. The figure depicts the access range of the mobile node MN moving from AP3 to the API, and the access control point is also transferred from AC2 to AC1. The access controller AC is the transport layer entity in the WLAN network.

The present invention is not limited to a WLAN environment. Figure 3 illustrates an abstract scenario when an end user moves between different transport layer entities within the same resource admission control system. The end user moves from one transport layer entity (transport layer entity 1) to another transport layer entity (transport layer entity 2), which are each controlled by the same RACF (resource admission control function). RACF has a communication interface with both SCF and NACF.

After the end user moves to the new transport layer entity, the new transport layer entity triggers the RACF to perform resource and policy update operations. The processing flow is shown in Figure 4. Includes:

Step 401: The mobile terminal user moves from one transport layer entity (transport layer entity 1) to another transport layer entity (transport layer entity 2).

Step 402: The mobile terminal user performs a network re-entry process; in the process, the transport layer entity usually interacts with the NACF to complete the user's authentication, authorization, and access information update operations, and the like.

Including the establishment of the initial data channel.

Step 404: The current transport layer entity notifies the link layer mobility event to the associated RACF, where

5 180800442 During the notification process, the transport layer entity may carry auxiliary information for guiding the RACF to do mobility switching. The auxiliary information includes one of a CPE (Customer Premises Equipment) identifier, a previous transport layer entity identifier (transport layer entity 1), a service control function entity location information, and a network attach control function entity location information. Or any combination. In general, the auxiliary information should include the end user identifier, that is, the CPE identifier and the previous transport layer entity identifier. Additionally, the auxiliary information may further include one or two of the service control function entity location information and the network attach control function entity location information. . The auxiliary information of the present invention is not limited to the above-described embodiments.

Step 405: The RACF performs mobility decision of the terminal user, and the RACF determines whether the terminal user moves within the control range of the same RACF. If yes, the RACF retrieves the resource reservation and policy decision information of the user in the database through the CPE identifier.

The method for determining whether the terminal user moves within the control range of the same RACF can use one of the following two methods: (1) If the auxiliary information includes the CPE identifier, the RACF determines whether the CPE identifier is stored locally, if any, The terminal user moves within the control range of the same resource admission control system; (2) if the auxiliary information includes the previous transport layer entity identifier, the RACF determines whether the transport layer entity identifier belongs to its own control range, and if so, the description The end user moves within the control of the same resource admission control system. The present invention is not limited to the above two methods, and other methods of determining whether the end user moves within the control range of the same RACF are within the scope of the present invention.

Step 406: The RACF obtains the service statistics information of the terminal user from the previous transport layer entity (the transport layer entity 1 in this embodiment) according to the user identifier or the policy identifier information, where the service statistics information includes the service identifier, the policy identifier information, and the billing identifier. One or any combination of byte traffic, packet loss rate/number of packet loss, packet average delay, and message burst, and may also include maximum, minimum, and average packet lengths; It is identified by a unique policy identification information, and the RACF communicates with the transport layer entity through the policy identification information. When the RACF obtains the service statistics from the previous transport layer entity, it can obtain only the service statistics related to the current service, and the service statistics that are not related to the current service.

Step 407: The RACF reserves resources and installs a policy on the current transport layer entity (the transport layer entity 2 in this embodiment) according to the resource reservation and policy decision information retrieved in step 405.

6 180800442 The resources reserved on the former transport layer entity are equal to the reserved resources stored in the database, and the installed policy is the same as the policy decision information stored in the database.

Step 408: The RACF sends part or all of the service statistics collected from the previous transport layer entity (the transport layer entity 1 in this embodiment) to the current transport layer entity (the transport layer entity 2 in this embodiment). The service statistics information that is delivered may be service statistics information that is only closely related to the current service, and the current transport layer entity continues to perform statistical work for the user as the statistical basis to ensure the integrity of the statistical data.

After step 408, the service of the end user is switched to the current transport layer entity. Since sufficient resources are reserved on the current transport layer entity before the user's service completes the handover, the continuity of the service quality can be guaranteed.

Step 409: The RACF releases the allocated resources and the installed policies on the previous transport layer entity (the transport layer entity 1 in this embodiment).

In different network environments, the above RACF can also be replaced by RACS (Resource Admission Control Subsystem) to perform the above functions.

7 180800442

Claims

Claim

A method for ensuring continuity of service quality in a resource admission control system, characterized in that:

When the end user moves from one transport layer entity to another transport layer entity, the current transport layer entity notifies the end user's link layer mobility event to the associated resource admission control system after completing the link layer mobility switching operation. ;

2. The method of claim 1 wherein:

The current transport layer entity carries the auxiliary information when the link layer mobility event of the terminal user is notified to the resource access control system, and the auxiliary information includes the terminal user identifier, the previous transport layer entity identifier, and the service control function entity location information. And one or any combination of the network attachment control function entity positioning information.

3. The method of claim 2, wherein:

The auxiliary information includes an end user identifier, and the resource admission control system determines, according to the terminal user identifier, whether the terminal user identifier is stored locally, and if yes, the terminal user is moved within the control range of the same resource admission control system. .

4. The method of claim 2, wherein:

The auxiliary information includes a previous transport layer entity identifier, and the resource admission control system determines whether the previous transport layer entity identifier belongs to its own control range. If yes, the terminal user is within the control scope of the same resource admission control system. mobile.

5. The method of claim 1 wherein:

The method for the resource admission control system to reserve resources on the current transport layer entity according to the resource reservation of the terminal user is: the resource admission control system reserves the same on the current transport layer entity as the reserved resource stored in the database. Resources.

8 180800442

6. The method of claim 1 wherein:

When the end user moves within the control range of the same resource admission control system, the resource admission control system further retrieves the policy decision information of the terminal user in its own database, and

7. The method of claim 1 wherein:

The resource admission control system further acquires the service statistics information of the terminal user from the previous transport layer entity according to the user identifier or the policy identifier information, and then sends the service statistics information to the current transport layer entity in whole or in part.

8. The method of claim 7 wherein:

When the service statistics information is obtained from the previous transport layer entity, only the service statistics related to the current service are obtained, and the service statistics related to the current service are sent to the current transport layer entity.

9. The method of claim 1 wherein:

After the resource admission control system reserves resources for the terminal user on the current transport layer entity, the service of the terminal user switches to the current transport layer entity.

10. The method of claim 9 wherein:

After the end user's service is switched to the current transport layer entity, the resource admission control system releases the resources allocated to the end user on the previous transport layer entity and the installed policies.

9 180800442