WO2011035582A1

WO2011035582A1 - Load sharing method and device for data flows of multiple interfaces in wimax system

Info

Publication number: WO2011035582A1
Application number: PCT/CN2010/072434
Authority: WO
Inventors: 夏云
Original assignee: 中兴通讯股份有限公司
Priority date: 2009-09-22
Filing date: 2010-05-04
Publication date: 2011-03-31
Also published as: CN101668010A

Abstract

A load sharing method and device for the data flows of multiple interfaces in a Worldwide Interoperability for Microwave Access (WIMAX) system are provided, which are used to solve the technical problem that when multiple firewalls are used to organize the network, a series of related access requests can not continuously be assigned to one firewall to implement the load sharing based on the user granularity. When an access service gateway (AGW) forwards a data message, a modulo operation is performed to obtain the remainder of the division of the value of the last byte of the Internet protocol (IP) address of an international network protocol convergence sub-layer (IP-CS) user or the value of the last byte of the media access control (MAC) address of an Ethernet convergence sub-layer (ETH-CS) user by the number of the multiple next hops which are obtained by a route lookup, and the number of the next hop is selected according to the result of the modulo operation. This method can realize that the AGW performs the load sharing for the data flows according to the user granularity when the multiple interfaces are started.

Description

Method and device for multi-interface data flow load sharing in WiMAX system

The present invention relates to the field of communications, and in particular, to a method and apparatus for data flow load sharing when an access gateway enables multiple interfaces in a WiMAX system. Background technique

WiMAX ( Worldwide Interoperability for Microwave Access) is a broadband wireless access technology. Figure 1 shows the WiMAX network architecture reference model, consisting of three logical entities: the terminal (mobile/fixed)/access service network (ASN) and the connected service network (CSN). The terminal is the final service recipient; the ASN is a common entity set related to the access service in the WiMAX network system; the CSN provides various network services for the terminal, and is a service provider.

The ASN and the CSN are connected through the R3 port. The ASN is composed of a base station (BS) and an ASN gateway AGW (ASN Gate Way), and the BS and the AGW are connected through an R6 port. The ASNs are connected through the R4 port.

Currently in WiMAX applications, IP user access is supported, and Ethernet user access is also supported. In the case of the Internet Protocol Convergence Sublayer (IP-CS) scenario, the R3 port is generally connected to the Internet by a firewall. The firewall and the AGW network use a private address segment, and the AGW receives user-related information. The access session request is firstly load-sharing to the corresponding firewall, and then processed by the firewall network address translation (NAT) and then sent to the Internet/Internet.

As shown in Figure 1, there are two kinds of user data packets on the R3 interface: User uplink data packets are forwarded from the R6 port and then forwarded from the R3 port. The user downlink data packets are received from the R3 port and processed by the AGW. Port forwarding. When the AGW is deployed in a large-capacity network, the AGW is configured as multiple interfaces. The capacity of the AGW and the number of firewall connections required by the user have exceeded the capacity of the general low-end firewall. In this case, a high-end firewall is required to meet the actual requirements. In the networking deployment, because the cost of the high-end firewall is too high, in the actual application process, it is necessary to consider using multiple low-configuration firewalls to achieve the effect of high-configuration firewall.

When using multiple firewalls for networking, you need to ensure the consistency of user sessions. That is, the AGW needs to ensure load balancing of multiple links and ensure that a series of related access requests can be allocated to a firewall. . That is, users on the entire AGW can share user packets to multiple firewalls for transmission according to user granularity.

At present, the load sharing mode of the AGW in the networking is generally not concerned with the related user information of the sent packets, but the packets are respectively allocated to multiple forwarding links one by one, that is, the packets are granular when forwarding. To determine the load sharing strategy, any firewall can receive all users' messages and cannot perceive the user's entire transmission session (TCP, UDP session).

Figure 2 shows the AGW firewall deployment and data flow load sharing.

As shown in Figure 2, in the network deployment, the AGW is configured with two interfaces and is connected to the same firewall. That is, there are two links between the AGW and the firewall. The AGW does not pay attention to the user information related to the specific packet when the load is load-balanced. The data flows of the user A and the user B are distributed to the links according to the packet granularity. In this way, although the firewall can perceive the entire transmission session of user A and user B, when the number of users is more, the throughput of the AGW will exceed the capacity of the general firewall. If the network mode is continued, it needs to be replaced with a high-end firewall. Increased the cost of networking deployment.

Figure 3 illustrates the AGW multiple firewall deployment and data flow load sharing.

In the networking deployment shown in Figure 3, two low-end firewalls are used instead of the high-end firewalls required in Figure 1. The AGW does not change the load sharing mode of the data flows (still using polling granularity). Therefore, the packets of user A and user B are sequentially forwarded to different links. The packets of each user are distributed to different firewalls, so that the firewall can receive all the users' packets, but cannot receive all the packets of a certain user, so the entire transmission session of the user cannot be perceived.

In the actual application scenario, if multiple firewalls are used for networking, session consistency must be achieved. The AGW needs to distribute the session of a specific user to the same firewall. After the firewall is NAT, the user will be exposed. address.

In addition, for a downlink data packet that the AGW forwards to the end user on the R6/R4 side, if a stable forwarding path is selected for each user's packet, the user packet flow can be better QoS to some extent. The feature, and the packets of the same user always go out from the same interface, which also reduces the possibility of out-of-order packets sent to the terminal.

The actual deployment scenario of the AGW has certain characteristics. The routing environment is relatively simple, the number of routing entries is relatively small, and the route changes are small. The probability of route flapping and route change occurring on the AGW is small (the AGW interface and the external switch fail). A route flapping occurs, which is caused by a fault. Therefore, the AGW can easily handle the forwarding link, and only considers the processing under the condition of stable routing. Summary of the invention

In view of the above, the main purpose of the present invention is to provide a method and apparatus for implementing data flow load sharing when a WiMAX access gateway enables multiple interfaces, which is used to solve the problem that when multiple firewalls are used for networking, A series of related access requests are kept assigned to a firewall to implement technical problems based on user granularity load sharing.

In order to achieve the above object, the technical solution of the present invention is achieved as follows:

A method for load sharing of multi-interface data streams in a WiMAX system includes:

When the access service gateway (AGW) forwards data packets, the IP address of the aggregation layer (IP-CS) user or the media access control (MAC) of the Ethernet convergence sublayer (ETH-CS) user according to the Internet Protocol The address is used to select the forwarding path. The forwarding path is selected by using IP-CS. The last byte of the user's IP address or the ETH-CS user's MAC address is used to count the number of multiple next hops obtained by the AGW when the packet is forwarded. Select the address of the next hop in the corresponding routing entry as the data forwarding address.

Further, when the access service gateway forwards the IP-CS user downlink data packet through the R6 and R4 interfaces, or forwards the Eth-CS user downlink packet through the R6 and R4 interfaces, the access service gateway is based on the innermost layer of the forwarded packet. The destination IP address of the IP packet or the destination MAC address of the innermost Ethernet packet is used to obtain the number of the next hops obtained by the AGW when the packet is forwarded.

Further, if the AGW finds that the routing entry changes when forwarding the packet, the AGW uses the new number of multiple next hops to select the forwarding path, and dynamically adjusts the forwarding path of the user packet flow. .

Based on the above method for multi-interface data flow load sharing in a WiMAX system, the present invention further provides an apparatus for implementing the foregoing method, where the apparatus is located at an access service gateway, and includes: a MAC address of a user;

a multiple next hop obtaining module, configured to search for a route according to the IP address or MAC address information obtained by the address obtaining module, so as to obtain the number of multiple next hops;

a next hop calculation module, configured to acquire, according to the IP address of the IP-CS user obtained by the address obtaining module or the last byte of the MAC address of the ETH-CS user, the multiple acquired by the multiple next hop obtaining module The number of next hops is taken to obtain the number of the next hop.

Further, when the device forwards the IP-CS user uplink data packet through the R3 and R4 interfaces, or the Eth-CS user uplink message is forwarded through the R4 interface, the address obtaining module obtains the most forwarded packet. The source IP address of the inner IP packet or the source MAC address of the innermost Ethernet packet of the forwarded packet.

Further, the device forwards the IP-CS user downlink data packet through the R6 and R4 interfaces. When the Eth-CS user downlink packet is forwarded through the R6 and R4 interfaces, the address obtaining module obtains the destination IP address of the innermost IP packet or the destination Ethernet packet destination MAC address of the forwarded packet. address.

Further, when the routing entry changes, the multiple next hop obtaining module uses the number of new multiple hops to select a forwarding path, and dynamically forwards a forwarding path of the user packet flow. Adjustment.

The above-mentioned technical solution can realize the problem that the data flow load sharing is performed by the AGW according to the user granularity when the multi-interface is started, and the solution idea is also applicable to the processing of the user packet forwarding by other wireless packet gateways (such as the GGSN, the PDSN, etc.). DRAWINGS

Figure 1 is a schematic diagram of a WiMAX network architecture reference model;

Figure 2 is a schematic diagram of AGW single firewall deployment and data flow load sharing;

Figure 3 is a schematic diagram of multiple AGW firewall deployments and data flow load sharing;

4 is a schematic diagram of multiple firewall deployments and data flow load sharing implemented in accordance with the method of the present invention;

FIG. 5 is a flowchart of path selection when an AGW forwards an IP-CS user uplink data stream on the R3 port according to an embodiment of the method of the present invention;

FIG. 6 is a flow chart of path selection for the AGW to forward the ETH-CS user downlink data stream on the R6 port according to an embodiment of the method of the present invention. detailed description

The core idea of the present invention is: for the IP-CS user, when the AGW forwards the data packet, the forwarding path is selected according to the IP address of the IP-CS user; for the Ethernet convergence sublayer (ETH-CS) The user forwards the data packet according to the Media Access Control (MAC) address of the ETH-CS user when the AGW forwards the data packet. The choice of forwarding path. The forwarding path is selected by: using the IP address in the data packet or the last byte of the MAC address to reserve the number of multiple next hops to obtain the number of the next hop. Here, the IP address refers to the IP address of the IP-CS user, and the MAC address refers to the MAC address of the corresponding terminal of the ETH-CS user. The number of multiple next hops refers to the number of times the AGW queries the route when forwarding the packet. The total number of multiple next hops corresponding to the routing entry. The method takes the last byte of the user IP/MAC address to the value of multiple next hops, and uses the calculated value as the number of the next hop of the route selected by the AGW to forward the data, that is, the selection. The address of the next hop in the routing entry corresponding to the number is used as the data forwarding address.

When the IP-CS user uplink data packet is forwarded through the R3 and R4 interfaces, the forwarding path is selected according to the selection method of the forwarding path according to the source IP address of the innermost IP packet of the forwarded packet.

When the IP-CS user downlink data packet is forwarded through the R6 and R4 interfaces, the forwarding path is selected according to the destination IP address selection method based on the destination IP address of the innermost IP packet of the forwarded packet. The Eth- is forwarded through the R6 and R4 interfaces. When the CS user downlinks the packet, the forwarding path is selected according to the destination MAC address of the innermost Ethernet packet of the forwarded packet according to the selection method of the forwarding path;

When the Eth-CS user uplink packet is forwarded through the R4 interface, the forwarding path is selected according to the selection method of the forwarding path of the innermost Ethernet packet source MAC address of the forwarded packet;

The load balancing of user data packets in the ETH-CS scenario does not include the processing of forwarding R3 uplink user data packets (not in the IP routing category).

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

Embodiment 1:

In this embodiment, a method for AGW to use IP-CS user (Simple IP) multi-interface data stream load sharing is described. This method describes the uplink data of the R3 port of the IP-CS user.

As shown in Figure 4, the AGW is connected to the Internet base station (BS) through two firewalls on the R3 side. The next two IP-CS users A and B have successfully accessed. User A's IP address is 10.0.0.2, and User B's IP address is 10.0.0.5.

After receiving the uplink data packet of user A from the R6 interface, the AGW first performs the general routing encapsulation (GRE) protocol decapsulation process, and obtains the source IP address of the decapsulated IP packet as 10.0.0.2, and records the last word of the IP address. The section value is 2. Then, the route that forwards the uplink packet is searched according to the information such as the destination address of the packet, and the number of multiple next hops of the route is 2. Finally, the last byte value of the IP address is used to reserve the number of multiple next hops (2% 2 = 0), so that the next hop number of the forwarded data packet is 0.

After receiving the uplink data packet of user B from the R6 interface, the AGW first performs GRE decapsulation processing to obtain the source IP address of the decapsulated IP packet as 10.0.0.5, and the last byte value of the recorded IP address is 5. . Then, according to the information such as the destination address of the packet, the route for forwarding the uplink packet is searched, and the number of the multiple next hops of the route is 2. Finally, the last byte value of the IP address is used to reserve the number of multiple next hops (5%2 = 1), so that the next megabyte number for forwarding the uplink data message is 1.

Through the above processing, the AGW always selects the first route to forward the uplink IP packet of user A to the firewall 1 and always selects the second route to forward the uplink IP packet of user B to the firewall 2. In this way, the firewall 1 can completely perceive the data flow of the user A, and the firewall 2 can completely perceive the data flow of the user B.

Figure 5 illustrates the path selection process when the AGW forwards the IP-CS user uplink data stream on the R3 interface: Step S502: Perform GRE decapsulation processing on the uplink GRE packet.

Step S504: Obtain a last byte of the source IP address of the decapsulated packet (the IP address of the IP-CS user);

Step S506: Find a route according to the information such as the destination address of the decapsulated packet, and obtain the number of multiple next hops.

Step S508: using the last byte of the IP address of the IP-CS user in step S506. Obtaining the number of multiple next hops to obtain the next hop number;

Step S510: The AGW selects a corresponding routing entry to send a packet according to the next hop number calculated in S508.

Embodiment 2:

In this embodiment, a method for the GW-CS user multi-interface data flow load sharing is described. This method describes the downlink data of the R6 interface of the ETH-CS user.

As in the first embodiment, as shown in FIG. 4, the AGW is connected to the BS through two switches on the R6 side. Two ETH-CS users A and B have successfully accessed the BS. User A's corresponding terminal MAC address is 00-19-21-AE-10-02, and user B's corresponding terminal MAC address is 00-19-21-AE-10-05.

After receiving the downlink data packet sent to user A from the R3 interface, the AGW first obtains the destination MAC address of the Ethernet packet as 00-19-21-AE-10-02, and records the last byte of the MAC address. Is 2. Then, the route that forwards the downlink packet is searched according to the information such as the IP address of the BS, and the number of multiple next hops in the routing table is 2. Finally, the last hop of the destination MAC address of the packet is used to reserve the remainder of the multiple hops (2% 2 = 0) to obtain the next hop number of the downlink Ethernet data packet.

Assume that after receiving the downlink data packet sent to user B from the R3 port, the AGW first obtains the destination MAC address of the Ethernet packet as 00-19-21-AE-10-05, and records the last MAC address. The byte is 5. Then, the route that forwards the downlink packet is searched according to the information such as the IP address of the BS, and the number of multiple next hops in the routing table is 2. Finally, the last byte of the destination MAC address of the message is used to reserve the number of multiple next hops (5% 2 = 1) to obtain the next hop number of the downlink Ethernet data >3⁄4 text.

Through the above processing, the AGW always selects the first route to forward the downlink Ethernet packet of user A to the BS, and always selects the second route to forward the downlink Ethernet "memand" of user B to the BS. Thus, the user packet flow Better server quality (QoS) features. Figure 6 illustrates the path selection process when the AGW forwards the ETH-CS downlink data stream on the R6 port: Step S602: Obtain the destination MAC address of the downlink Ethernet packet, and read the last byte of the MAC address.

Step S604: Encapsulate the R6 tunnel, and find a route according to the information such as the IP address corresponding to the BS, and obtain the number of multiple next hops.

Step S606: Calculate the next hop number by using the last byte of the MAC address to calculate the number of the multiple next hops;

Step S608: The AGW selects a corresponding routing entry to send a packet according to the next hop number calculated in S606.

In the above two embodiments, if the routing entry changes, the AGW uses the new number of multiple next hops to select the forwarding path, that is, the AGW can dynamically adjust the forwarding path of the user packet flow. . At this time, the user's packet flow may be switched to another firewall, which may cause the user's current data stream to be interrupted. However, the result of such processing is the current stream, which is still available when the user re-initiates the streaming.

Embodiment 3:

Based on the method for load balancing of multi-interface data streams in a WiMAX system according to the present invention, the present invention further provides an apparatus for implementing the foregoing method, where the apparatus is located in an access service gateway, and mainly includes an address acquisition module and a multiple next hop acquisition module. And next hop calculation module.

The address obtaining module is configured to obtain the IP address of the IP-CS user or the MAC address of the ETH-CS user from the forwarded message; the access service gateway forwards the IP-CS user uplink data packet through the R3 and R4 interfaces or through the R4 When the interface forwards the Eth-CS user uplink packet, the address obtaining module obtains the source IP address of the innermost IP packet of the forwarded packet or the source MAC address of the innermost Ethernet packet of the forwarded packet. When the access service gateway forwards the IP-CS user downlink data packet through the R6 and R4 interfaces, or forwards the Eth-CS user downlink packet through the R6 and R4 interfaces, the address acquisition module obtains the most forwarded packet. The IP address of the inner IP packet or the innermost Ethernet packet. The MAC address of the text.

The multiple next hop obtaining module is configured to search for a route according to the IP address or the MAC address information obtained by the address obtaining module, so as to obtain the number of multiple next hops;

The next hop calculation module is configured to obtain, according to the IP address of the IP-CS user obtained by the address obtaining module or the last byte of the MAC address of the ETH-CS user, the multiple acquired by the multiple next hop acquisition module The number of one hops is taken to obtain the number of the next hop.

When the routing entry changes, the multiple next hop acquisition module uses the new number of multiple next hops to select the forwarding path, and dynamically adjusts the forwarding path of the user packet flow.

The above is only the preferred embodiment of the present invention, and is not intended to limit the present invention, and various modifications and changes can be made to the present invention. Any modifications, equivalent substitutions, improvements, etc. within the spirit and scope of the invention are intended to be included within the scope of the invention.

Claims

Claim

A method for load sharing of multi-interface data streams in a WiMAX system, characterized in that:

When accessing the service gateway (AGW) to forward data packets, use the IP address of the Internet Protocol Convergence Sublayer (IP-CS) user or the Media Access Control (MAC) of the Ethernet Convergence Sublayer (ETH-CS) user. The last byte of the address takes the number of multiple next hops obtained by the query route, and uses the result of the redundancy as the number of the next hop to select the address of the next hop in the corresponding routing entry as the data forwarding address.

The method according to claim 1, wherein the access service gateway forwards the IP-CS user uplink data packet through the R3 and R4 interfaces, or forwards the Eth-CS user uplink message through the R4 interface. The way to select the forwarding path is as follows:

According to the source IP address of the innermost IP packet of the forwarded packet or the last byte of the source MAC address of the innermost layer of the forwarded packet, the AGW queries the route to obtain multiple routes. The number of one hops is taken to obtain the number of the next hop.

3. The method according to claim 1, wherein the access service gateway forwards the Eth-CS user downlink message through the R6 and R4 interfaces when forwarding the IP-CS user downlink data packet through the R6 and R4 interfaces. In the text, the way to select the forwarding path is as follows:

According to the destination IP address of the innermost IP packet of the forwarded packet or the destination MAC address of the innermost layer Ethernet packet, the number of multiple next hops obtained by the AGW in querying the route when the packet is forwarded is used. Get the number of the next hop.

The method according to claim 1, 2 or 3, wherein, if the AGW finds that the routing entry changes when forwarding the packet, the AGW uses the new number of multiple next hops to forward the packet. The path is selected to dynamically adjust the forwarding path of the user packet flow.

5. A device for multi-interface data flow load sharing in a WiMAX system, characterized in that The device is located at the access service gateway, and includes: a MAC address of the user;

The multiple next hop obtaining module is configured to search for a route according to the IP address or the MAC address obtained by the address obtaining module, so as to obtain the number of multiple next hops;

The device according to claim 5, wherein when the device forwards an IP-CS user uplink data packet through the R3 and R4 interfaces, or forwards the Eth-CS user uplink message through the R4 interface, The address acquisition module obtains the source IP address of the innermost IP packet of the forwarded packet or the source MAC address of the innermost Ethernet packet of the forwarded packet.

The device according to claim 5, wherein, when the device forwards the downlink data packet of the IP-CS user through the R6 and R4 interfaces, or forwards the Eth-CS user downlink packet through the R6 and R4 interfaces, The address obtaining module obtains the destination IP address of the innermost IP packet or the destination MAC address of the innermost layer Ethernet packet of the forwarded packet.

The device according to claim 5, 6 or 7, wherein, when the routing entry changes, the multiple next hop obtaining module uses the number of new multiple next hops to perform The selection of the forwarding path dynamically adjusts the forwarding path of the user packet flow.