The present invention relates to communication field, and specifically, to a method and system for controlling home gateway policy in the NGN (Next Generation Network).
In the NGN, since a bearer network uses packet technology, in particular the IP technology, its problem on QoS (Quality of Service) is especially outstanding. The ITU (International Telecommunication Union) proposed to use an RACF (Resource and Admission Control Function) to solve the QoS problem of the NGN bearer network.
The principal function of the RACF is to perform resource and admission control based on an operation policy rule and according to the QoS information that a user subscribed and available resources inside a network. The RACF shields the difference of the bearer layers for the application layer and maps the QoS attributes of the application layer to the bearer layers, so that a bearer layer transmission entity can provide QoS guarantee for a media stream in a session under its guidance.
In the latest RACF draft of the ITU, the functional architecture of the RACF of the ITU-T (International Telecommunication Union-Telecommunication Standardization Sector) is illustrated in
As the service stream of a user may pass through some different sub-network segments in the network, in order to ensure a terminal-to-terminal QoS, after making the policy decision according to the resource request of the service stream, the RACF needs to send down the policy to the policy execution functions at the boundary points of these sub-network segments, and the policy execution functions mark the QoS priority mark or label of the network segments on the corresponding traffic according to the policy to ensure its QoS in the network segments.
The main content of the policy comprises a service stream template and QoS information, and the QoS information comprises gate control, uplink and downlink traffic bandwidth, QoS priority and etc.
The service stream template (such as IP quintuple, i.e., the protocol, the source address, the destination address, the source port and the destination port of a packet) is configured to match packets passing by, and if the matching is successful, the QoS control described in the policy is performed for it.
The QoS priority describes the service priority of the service stream, has different mappings at different transport layer network segments, and the value of the mapped priority will be configured in a field of a packet header for marking the service priority, such as the DSCP (DiffServ Code Point) field of the IP header, the Priority field in the VLAN (Virtual Local Area Network) label, and the CoS (Class of Service) field in the MPLS (Multi Protocol Label Switching Architecture) label, and a transport layer entity will perform forwarding according to the priority in a corresponding head to ensure the time delay of a packet stream.
The uplink bandwidth is the maximum uplink traffic bandwidth allowable for the service data traffic; the downlink bandwidth is the maximum downlink traffic bandwidth allowable for the service data traffic.
The gate control refers to whether to allow a certain service stream to pass, and when a user is initially on line, the RACF can send down some gate controls to a user according to its subscribed service, and subsequently users can dynamically apply for updating the gate controls.
When the BRAS performs policy execution, when the uplink traffic of the user passing the BRAS, the BRAS identifies it according to a packet template (such as the IP quintuple) in the policy, if it matches, a corresponding QoS priority label will be marked for the IP header of the packet according to the QoS information in the policy, and the following IP devices will ensure the QoS of the packet according to the priority label; when the downlink traffic of the user passing the BRAS, the BRAS will process the downlink traffic in a similar way according to the policy, that is, marking the QoS priority label on its layer 2 header such as a VLAN Tag according to the policy, and the layer 2 devices in the downlink direction will ensure its QoS according to the label.
In view of the current operating situations of operators, the convergence layer of a metropolitan area network, i.e., from the first local office equipment connecting the user to a service access server (BRAS/SR), has a heavy load, so it is especially necessary to provide an effective QoS guarantee for this segment of network. However, the current RACF control method can only provide effective QoS control for the downlink packets of the convergence layer, and QoS control can only be performed when the uplink packets reach the BRAS, which is imperfect. Hence, it is necessary to perform QoS control at both uplink and downlink entrances of the convergence layer.
On the other hand, in recent years, the incomes of fixed network operators from voice and pure broadband services are undergoing a continuous decrease, in view of changes in competition and demands, the fixed network operators need to turn from single service operation of pure data and voice to multi-service operations combining application, video, voice and data, so as to keep and attract more family users. In view of technologies and products, a terminal product that can support multiple services, multiple ports and can differentiate different service qualities is in need, i.e., a home gateway. The QoS control problem of the home gateway is the key point for the operators to develop digital family services.
The present invention aims at solving the technical problem of providing a method and system for controlling home gateway policy to solve the problem in the prior art that the convergence layer of the metropolitan area network has a heavy load and thus it is difficult to perform effective QoS control over the uplink packets.
To solve the above problem, the present invention provides a method for controlling home gateway policy. An RACF sends down a policy to a home gateway, and a policy execution is performed by the home gateway for an uplink packet passing through the home gateway according to the policy received.
Further, the content of the policy at least comprises a service stream template and QoS information, and the QoS information comprises: gate control, uplink and downlink traffic bandwidth, and QoS priority; the home gateway identifies the uplink packet passing through the home gateway according to the service stream template, and performs the following operations for identified packet stream according to the policy:
(1) executing gate control; or
(2) restricting its uplink and downlink bandwidth; or
(3) performing QoS priority process for the identified packet stream supported by its uplink according to the type of the uplink accessed by the home gateway and the QoS priority.
Further, when the type of the uplink accessed by the home gateway is a digital subscriber access multiplexer, multiple permanent virtual channels between the home gateway and the digital subscriber access multiplexer are respectively set to be corresponding to different QoS levels of the QoS priority; the home gateway enables the uplink packet to access the permanent virtual channels of corresponding QoS levels according to the QoS priority; the digital subscriber access multiplexer, according to the QoS levels of the permanent virtual channels, marks a corresponding priority mark on a Virtual Local Area Network, VLAN, label or on both the VLAN label and an IP header of the packets in the channels.
Further, when the type of the uplink accessed by the home gateway is an Ethernet switch, the home gateway marks, according to the content of the policy, a corresponding QoS priority mark on the VLAN label or on both the VLAN label and the IP header of the corresponding service stream of the uplink packet.
Further, the home gateway is configured with a static policy which is activated or deactivated by the RACF through a policy ID.
The present invention also provides a system for controlling home gateway policy , which connected to a layer 2 convergence network and a service access server, comprising a Resource and Admission Control Function, RACF, and a home gateway, and the home gateway comprises a home policy execute function entity, wherein, the RACF is configured to send down a policy to the home policy execute function entity and the service access server; the home policy execute function entity is configured to perform a policy execution for an uplink packet passing through the home gateway after receiving the policy.
Further, the home policy execute function entity comprises: an identifying module, configured to identify the uplink packets passing through the home gateway according to the service stream template in the policy content, and send the same to a QoS executing module if the identification is successful; the QoS executing module, configured to perform gate control for packet stream, restrict the uplink row bandwidth of the packet stream, and perform a QoS priority process for the packet stream supported by its uplink according to the type of the uplink accessed by the home gateway and the QoS priority.
Further, the system comprises a digital subscriber access multiplexer, and the home gateway accesses the digital subscriber access multiplexer, the digital subscriber access multiplexer accesses the service access server through a layer 2 convergence network, and multiple permanent virtual channels between the home gateway and the digital subscriber access multiplexer correspond to different QoS levels of the QoS priority respectively; the QoS executing module enables the uplink packet to access the permanent virtual channels of corresponding QoS levels according to the QoS priority; the digital subscriber access multiplexer marks, according to the QoS levels of the permanent virtual channels, a corresponding priority mark on the VLAN label or on both the VLAN label and the IP header of the packet in the channels.
Further, the home gateway accesses an Ethernet switch and directly accesses the service access server through a layer 2 convergence network; the QoS executing module marks, according to the policy content, a corresponding QoS priority mark on the VLAN label or on both the VLAN label and the IP header of the corresponding service stream of the uplink packet.
Further, the home policy execute function entity comprises a static policy configuring module, configured to configure a policy statically, which is activated or deactivated by the RACF through a policy ID.
With the policy control method and system of the present invention, the policy is sent down to the home gateway by the RACF, QoS control is performed for the uplink packet passing through the home gateway before the BRAS, effective QoS assurance is provided for the uplink packet before arriving at the BRAS, and meanwhile, the problem of heavy load of a convergence layer of a metropolitan area network in the prior art is solved.
The present invention will be further detailed hereinafter in conjunction with the drawings and the embodiments, which shall not be construed as limitations on the present invention.
As shown in
The PE-FE of the BRAS performs a policy execution for the downlink traffic passing through the BRAS according to the policy sent down, and may either perform the policy execution again for the uplink traffic passing through the BRAS, or not perform the policy execution but only makes a check or does nothing.
The policy control method of this embodiment comprises: the RACF dynamically generates a policy and sends it down to the home gateway and the IP boundary point device BRAS, comprising generating and sending down the policy when the user goes on line and initiates a resource request:
1. The processing flow of triggering the RACF to send down the policy to the home gateway when the user goes on line. When a user is on line, identity authentication interaction will be preformed first, and when it is determined that the identity of the user is legal, it is necessary to notify the RACF to generate an initial policy for the user, then sent it down to a transport layer policy execute entity for execution (comprising the HPE-FE at the home gateway), and the specific flow is shown in
(401) the PD-FE receives a notification that the user goes on line;
The notification that the user goes on line notifying the PD-FE can be performed by the IP boundary point device such as the BRAS, and can also be performed by an NACF such as an AAA server (Authentication, Authorization, and Accounting), and when the NACF notifies the PD-FE that the user goes on line, the subscription information of the user can also be sent to the PD-FE together within the notification packet;
(402) the PD-FE checks whether the notification packet includes the subscription information of the user, if the subscription information of the user is not included, the PD-FE will interact with the NACF to acquire the subscription information of the user;
(403) meanwhile, the PD-FE will also check, according to the QoS related information in the subscription information of the user, the TRC-FE to see whether all the current use of the resources satisfy the user, so as to generate an initial policy;
(404a, b) the PD-FE sends down the initial policy respectively to the HPE-FE and the PE-FE;
(405a, b) the HPE-FE and the PE-FE respectively return a response to the policy sent down.
2. The processing flow that the RACF sends down the policy to the home gateway when the user requests the service. When the user hopes to dynamically initiates a service with QoS guarantee, it will determine the QoS of the service through the negotiation of a service layer. A service control layer initiates a resource request to the RACF according to the negotiated QoS, and the RACF generates a QoS policy of the transport layer which is then sent down to the transport layer policy execute entity (including the HPE-FE in the home gateway) for execution, and the specific flow is shown in
(501) an SCF initiates the resource request to the PD-FE according to the QoS negotiated by the service layer;
(502) the PD-FE authorizes the request, and makes a preliminary policy decision, if the PD-FE does not have the subscription information of the user, it will acquire it by interacting with the NACF;
(503) the PD-FE requests resources from the TRC-FE, the TRC-FE judges the request according to the situation of current resources, and returns whether there are enough resources;
(504) the PD-FE makes a final admission policy decision according to resource availability;
(505a, b) the PD-FE sends down the policy respectively to the HPE-FE and the PE-FE;
(506a, b) the HPE-FE and the PE-FE respectively return a response to the policy sent down;
(507) the PD-FE returns a resource request response to the SCF.
In the above steps what is sent down to the home gateway by the RACF is a dynamically generated policy, but the HPE-FE itself can also statically configure some policies to which enabling operation can be performed by the RACF through a policy ID, such as activating and deactivating operations.
After the RACF has sent down the policy to the HPE-FE at the home gateway, the HPE-FE performs policy control for the uplink packets passing through the home gateway, for example, the operations such as matching the uplink packets passing by, identifying the packet stream matching a packet template in the policy, performing gate control (gate opening or gate closing, i.e., whether to allow the packet stream to pass) according to the content of the policy, restricting the uplink and downlink bandwidth of the packet stream, and marking a priority label supported by the uplink on the identified packet stream according to the type of the uplink accessed by the home gateway and the QoS priority.
The flow that the HPE-FE performs the policy control will be described hereinafter through the two most common access network methods.
In this situation, the uplink interface of the home gateway is an ATM (Asynchronous Transfer Mode) interface, and it accesses the DSLAM (Digital Subscriber Line Access Multiplexer) via the ATM, the DSLAM then accesses the BRAS through a layer 2 Ethernet convergence network (consisting of some switches), and the networking is shown in
In this networking mode, the home gateway will establish several PVCs (Permanent Virtual Channel) corresponding to different QoS levels (such as constant bit rate, variable bit rate, and uncertain bit rate) with DSLAM.
The home gateway filters the uplink packets passing by according to the policy sent down, identifies a service stream matching the packet template in the policy, and the home gateway enables the packets to access the PVC channels of corresponding QoS levels according to the QoS description in the policy. The DSLAM marks corresponding priority levels on the VLAN label of the packets in the channels according to the QoS levels of the PVC channels. The subsequent layer 2 devices will forward the packets according to the priority levels to guarantee the QoS.
For the BRAS, since it comprises the function of the PE-FE, for the uplink packets, the BRAS can mark corresponding priority levels on the IP header of the packets according to the policy; or, the priority levels in the IP header can also be marked by the home gateway, the BRAS only checks it or does nothing.
In this situation, it is equivalent to that the home gateway directly accesses the layer 2 Ethernet convergence network and accesses the BRAS through convergence.
In this networking mode, the home gateway directly marks corresponding priority levels on the VLAN labels of the corresponding uplink packet stream according to the policy, the Ethernet switch in the layer 2 Ethernet convergence network forwards the packets according to the priority levels to guarantees the QoS.
For the BRAS, since it comprises the function of the PE-FE, for the uplink packets, the BRAS can mark corresponding priority levels on the IP header of the packets according to the policy, or the priority levels in the IP header can also be marked by the home gateway, the BRAS only checks it or does nothing.
To realize the above method for controlling home gateway policy, the system for controlling home gateway policy corresponding thereto is connected to the layer 2 convergence network and the service access server, comprising an RACF and a home gateway, characterized in that the home gateway comprises a home policy execute function entity, wherein, the RACF is configured to send down a policy to the home policy execute function entity and the service access server; the home policy execute function entity is configured to perform policy execution for an uplink packet passing through the home gateway after receiving the policy, comprises: an identifying module, configured to identify the uplink packet passing through the home gateway according to the service stream template in the policy content, and send the same to a QoS executing module if the identification is successful; a static policy configuring module, configured to configure a policy statically, which is activated or deactivated by the RACF through a policy ID; and the QoS executing module, configured to perform gate control for the packet stream, restrict the uplink row bandwidth of the packet stream, and perform a QoS priority process for the packet stream that is supported by its uplink according to the type of the uplink accessed by the home gateway and the QoS priority.
As discussed above, the home gateway can access the service access server through the digital subscriber access multiplexer or the Ethernet switch.
With the policy control method and system of the present invention, the policy is sent down to the home gateway through the RACF, QoS control is made for the uplink packets passing through the home gateway before the BRAS, effective QoS assurance is provided for the uplink packets before arriving at the BRAS, and meanwhile, the problem of heavy load of a convergence layer of a metropolitan area network in the prior art is solved.
Of course, the present invention can have many other embodiments, and those skilled in the art may make various corresponding changes and variations to the present invention without departing from the spirit and essence of the present invention, and such corresponding changes and variations shall all be contained within the scope of protection of the annexed claims of the present invention.
Number | Date | Country | Kind |
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200810004399.5 | Jan 2008 | CN | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/CN08/71067 | 5/23/2008 | WO | 00 | 7/22/2010 |