CN107317768B

CN107317768B - Traffic scheduling method and device

Info

Publication number: CN107317768B
Application number: CN201610273447.5A
Authority: CN
Inventors: 刘建锋
Original assignee: New H3C Technologies Co Ltd
Current assignee: New H3C Technologies Co Ltd
Priority date: 2016-04-27
Filing date: 2016-04-27
Publication date: 2020-01-03
Anticipated expiration: 2036-04-27
Also published as: CN107317768A; WO2017186122A1

Abstract

The application provides a traffic scheduling method and a traffic scheduling device, wherein the method comprises the following steps: grouping BRAS network elements in a resource pool, wherein each group comprises at least two BRAS network elements; a packet is appointed for a convergence switch, and a VXLAN tunnel is established between the convergence switch and each BRAS network element in the packet, so that the convergence switch sends a first message of a client received from an AC interface to each BRAS network element in the packet through the VXLAN tunnel; and selecting a BRAS network element responding to the first message according to a preset control mode, so that the convergence switch sends the subsequent message of the client received from the AC interface to the selected BRAS network element through the VXLAN tunnel.

Description

Traffic scheduling method and device

Technical Field

The present application relates to the field of network communication technologies, and in particular, to a traffic scheduling method and apparatus.

Background

The Broadband Remote Access Server (BRAS) is an Access gateway facing Broadband network application, is located at the edge layer of a backbone network, and can complete data Access of an IP (Internet Protocol)/ATM (Asynchronous Transfer Mode) network of user bandwidth, thereby realizing Broadband Internet Access of commercial buildings and residential quarters.

In a Metropolitan Area Network (MAN) networking model, a BRAS is deployed in a convergence machine room of the MAN, and a broadband user is accessed by an OLT (Optical Line Terminal) and connected to the BRAS through a convergence switch (HJSW).

Disclosure of Invention

In view of this, the present application provides a traffic scheduling method and apparatus.

Specifically, the method is realized through the following technical scheme:

in one aspect, a traffic scheduling method is provided, and the method includes:

grouping BRAS network elements in a resource pool, wherein each group comprises at least two BRAS network elements;

a packet is appointed for a convergence switch, and a VXLAN tunnel is established between the convergence switch and each BRAS network element in the packet, so that the convergence switch sends a first message of a client received from an AC interface to each BRAS network element in the packet through the VXLAN tunnel;

and selecting a BRAS network element responding to the first message according to a preset control mode, so that the convergence switch sends the subsequent message of the client received from the AC interface to the selected BRAS network element through the VXLAN tunnel.

In another aspect, an apparatus for scheduling traffic is further provided, where the apparatus includes:

the grouping module is used for grouping the BRAS network elements in the resource pool, and each group comprises at least two BRAS network elements;

the system comprises an establishing module, a forwarding module and a forwarding module, wherein the establishing module is used for assigning a group for a convergence switch and establishing a VXLAN tunnel between the convergence switch and each BRAS network element in the group so that the convergence switch sends a client first message received from an AC interface to each BRAS network element in the group through the VXLAN tunnel;

and the selection module is used for selecting the BRAS network element responding to the first message according to a preset control mode, so that the convergence switch sends the subsequent message of the client received from the AC interface to the selected BRAS network element through the VXLAN tunnel.

Through the technical scheme of the application, at least two BRAS network elements in a resource pool are divided into a group in advance, a group is assigned to any aggregation switch, a VXLAN tunnel is established between the aggregation switch and each BRAS network element in the group, a group of VXLAN tunnels is obtained, an AC interface on the aggregation switch corresponds to the group of VXLAN tunnels, and therefore after the aggregation switch receives a head message of any client from the AC interface, the head message can be sent to each BRAS network element in the group through the VXLAN tunnel; and then, according to a preset control mode, selecting a BRAS network element responding to the first message from the group, so that the convergence switch can send the subsequent message to the selected BRAS network element through a VXLAN tunnel after receiving the subsequent message of the client from the AC interface. By the method, the user data stream of any client connected with the AC interface is dispatched to the selected BRAS network element, so that the dispatching of the user data stream among the BRAS network elements in the same group is realized.

Drawings

FIG. 1 is a networking architecture diagram of an access network, shown in an exemplary embodiment of the present application;

fig. 2 is a flowchart illustrating a controller establishing a VXLAN tunnel between a aggregation switch and each BRAS network element within the same packet according to an exemplary embodiment of the present application;

fig. 3 is a flowchart illustrating a process of forwarding a PPPoE header message by a convergence switch according to an exemplary embodiment of the present application;

fig. 4 is a flowchart illustrating that an aggregation switch performs forwarding processing on a unicast packet sent by a PPPoE client according to an exemplary embodiment of the present application;

FIG. 5 is a diagram illustrating a hardware architecture of a controller according to an exemplary embodiment of the present application;

fig. 6 is a schematic structural diagram of a traffic scheduling apparatus according to an exemplary embodiment of the present application.

Detailed Description

Reference will now be made in detail to the exemplary embodiments, examples of which are illustrated in the accompanying drawings. When the following description refers to the accompanying drawings, like numbers in different drawings represent the same or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present application. Rather, they are merely examples of apparatus and methods consistent with certain aspects of the present application, as detailed in the appended claims.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. As used in this application and the appended claims, the singular forms "a", "an", and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It should also be understood that the term "and/or" as used herein refers to and encompasses any and all possible combinations of one or more of the associated listed items.

It is to be understood that although the terms first, second, third, etc. may be used herein to describe various information, such information should not be limited to these terms. These terms are only used to distinguish one type of information from another. For example, first information may also be referred to as second information, and similarly, second information may also be referred to as first information, without departing from the scope of the present application. The word "if" as used herein may be interpreted as "at … …" or "when … …" or "in response to a determination", depending on the context.

The embodiment of the application provides a traffic scheduling method and a traffic scheduling device capable of applying the method.

A networking architecture of an access network according to an embodiment of the present application is shown in fig. 1, where the access network mainly includes: a controller, a BRAS network element and a convergence switch (HJSW). A VXLAN (Virtual eXtensibleLAN) tunnel is established between the BRAS network elements and the aggregation switch, and a VXLAN tunnel is established between one aggregation switch and each BRAS network element in the same group, wherein the BRAS network element of the group consists of at least two BRAS network elements; the client accesses the aggregation switch through the OLT, and a QinQ (double-layer label) tunnel is established between the OLT and the aggregation switch.

The access network shown in fig. 1 may specifically be a metropolitan area network or an enterprise campus network, which is not limited in this embodiment of the present application.

The controller, BRAS network element and aggregation switch are described separately below.

The controller mainly has the following functions:

BRAS resource management: the controller stores a resource pool, the resource pool comprises a plurality of BRAS network elements, all the BRAS network elements have equal functions and can be mutually backed up; the controller may obtain, from a BRAS network element in the resource pool, network element information of the BRAS network element, where the network element information includes: the number of clients accessing the BRAS network element, the traffic on the BRAS network element, the CPU (central processing unit) load of the BRAS network element, the working state of the BRAS network element, and the like; in addition, the controller groups the BRAS network elements in the resource pool, and divides at least two BRAS network elements into the same group;

user resource management: obtaining user resource information from a convergence switch, wherein the user resource information comprises: the number of clients accessing the aggregation switch, VLAN (virtual local area network) information on the aggregation switch, VLAN to which each client belongs, and the like;

and (3) tunnel resource management: managing and allocating VXLAN tunnel resources, for example, allocating VXLAN IDs to VXLAN tunnels to be established, establishing VXLAN tunnels between a convergence switch and each BRAS network element in the same group, deleting VXLAN tunnels between the convergence switch and each BRAS network element in the same group, and recovering corresponding VXLAN IDs after VXLAN tunnels between the convergence switch and each BRAS network element in the same group are deleted;

and (3) service scheduling management: and dispatching the data flow of a certain client accessed on the aggregation switch to a proper BRAS network element.

The functions of the BRAS network element mainly include: supporting a VXLAN tunnel, decapsulating and obtaining a message sent by a client, such as a PPPoE (Point to Point Protocol over Ethernet) message and an IPoE (Internet Protocol over Ethernet) message, from the VXLAN tunnel, and sending the message to the client through the VXLAN tunnel; the access service can be provided for all clients in the range of the access network; BRAS network elements in the same group are backups of each other; the BRAS network element can be a physical BRAS device, and can also be BRAS virtualization software (vbars) based on an x86 server platform.

The functions of the aggregation switch mainly include: and supporting the VXLAN tunnel, forwarding the message sent by the client to a BRAS network element of the opposite end through the VXLAN tunnel, and forwarding the message obtained by de-encapsulation from the VXLAN tunnel to the client.

The traffic scheduling method of the embodiment of the application comprises the following steps:

first, the controller needs to establish a VXLAN tunnel between the aggregation switch and each BRAS network element in the same packet, as shown in fig. 2, the controller needs to perform the following steps:

step S101, at least two BRAS network elements in a local resource pool are divided into the same group, and each group comprises at least two BRAS network elements;

the BRAS network element in the resource pool may be divided into a plurality of packets, via step S101.

Step S102, a group (for the convenience of description, marked as group 1) is assigned to the aggregation switch, and a VXLAN tunnel is established between the aggregation switch and each BRAS network element in the group 1;

specifically, for each BRAS network element in the packet 1, a Tunnel interface is configured on the aggregation switch, and a source IP address of the Tunnel interface is specified as an IP address of the aggregation switch, and a destination IP address of the Tunnel interface is specified as an IP address of the BRAS network element; create a VSI (virtual switch instance) on the aggregation switch, create VXLAN (denoted VXLAN1 for descriptive convenience) within the VSI; binding the AC (access circuit) interface, the VSI, and all configured Tunnel interfaces. Thus, on the aggregation switch, the AC interface, the VSI, all Tunnel interfaces, and VXLAN1 form a correspondence.

Aiming at each BRAS network element in the packet 1, configuring a Tunnel interface on the BRAS network element, and designating a source IP address of the Tunnel interface as an IP address of the BRAS network element and a destination IP address as an IP address of the convergence switch; creating a VSI on the BRAS network element, creating VXLAN1 within the VSI; and binding the VSI and the Tunnel interface. Thus, the VSI, Tunnel interface, and VXLAN1 form a correspondence on each BRAS network element within packet 1.

Through the above steps S101 and S102, the controller establishes VXLAN tunnels between a aggregation switch and each BRAS network element in the same packet, so as to obtain a set of VXLAN tunnels, an AC interface on the aggregation switch corresponds to the set of VXLAN tunnels, and a VXLAN tunnel of such a structure may be referred to as an umbrella-shaped VXLAN tunnel.

After VXLAN tunnel establishment between the aggregation switch and each BRAS network element in the packet 1 is completed, the client can access one of the BRAS network elements through the aggregation switch. In practical implementation, the access network may apply various authentication methods, such as PPPoE and IPoE. When PPPoE authentication is applied, a PPPoE client is accessed, and when IPoE is applied, an IPoE client is accessed. The following description is mainly directed to the case of PPPoE and IPoE, respectively. Those skilled in the art can understand that the processing method of the embodiment of the present application can also be applied to other authentication methods of broadband users, and the present application is not limited thereto.

The client refers to a terminal device used by a user, and one user corresponds to one client.

1. Authentication using PPPoE

When a PPPoE connection is to be established, a PPPoE client first sends a first message in the PPPoE connection establishment process, which is hereinafter referred to as a PPPoE first message, and at this time, a flow of forwarding the PPPoE first message by a convergence switch is shown in fig. 3, and includes the following steps:

step S201, the convergence switch receives a PPPoE first message sent by a PPPoE client from an AC interface, wherein the PPPoE first message is a broadcast message;

step S202, the convergence switch finds out each VXLAN tunnel corresponding to the VXLAN to which the PPPoE first message belongs, packages the PPPoE first message according to the VXLAN tunnel, and sends the VXLAN message obtained by packaging to a BRAS network element of an opposite terminal; thus, the PPPoE header message is sent to all BRAS network elements in packet 1.

After step S201, the convergence switch also learns the source MAC address of the PPPoE first packet, so that an MAC entry is added to the MAC address table corresponding to the VXLAN to which the PPPoE first packet belongs, where the MAC entry includes a correspondence between the source MAC address of the PPPoE first packet and the AC interface that receives the PPPoE first packet, that is, a correspondence between the MAC address of the PPPoE client and the AC interface that receives the PPPoE first packet.

As can be seen from step S201 and step S202, the processing flow of the aggregation switch for the broadcast packet received from the AC interface is as follows: and broadcasting the message to all BRAS network elements in the group 1 through a VXLAN tunnel corresponding to the VXLAN to which the message belongs, wherein the processing of the unknown unicast message by the convergence switch is the same as that of the broadcast message.

After receiving a VXLAN message encapsulated with a PPPoE first message, a BRAS network element decapsulates the VXLAN message to obtain the PPPoE first message, and then learns a source MAC address of the PPPoE first message, so that an MAC entry is added to an MAC address table corresponding to a VXLAN to which the VXLAN message belongs, wherein the MAC entry includes: the source MAC address of the PPPoE first message corresponds to the VXLAN tunnel that received the VXLAN message, that is, the MAC address of the PPPoE client corresponds to the VXLAN tunnel that received the VXLAN message.

In addition, the BRAS network element also carries out corresponding processing according to the PPPoE first message and any one of the following two modes.

The first method is as follows: strong control mode of controller

The BRAS network element reports the PPPoE first message to the controller, because the convergence switch broadcasts the PPPoE first message to all BRAS network elements in the group 1, and the BRAS network elements report the PPPoE first message to the controller, the controller receives a plurality of same PPPoE first messages, and then the controller selects one BRAS network element from all BRAS network elements reporting the PPPoE first messages according to a preset selection rule, and sends a response notice to the selected BRAS network element; after receiving the response notification from the controller, the selected BRAS network element generates a response message for the PPPoE first message, finds a corresponding VXLAN tunnel in a MAC address table corresponding to the VXLAN to which the response message belongs according to a destination MAC address of the response message (i.e., an MAC address of the PPPoE client), encapsulates the response message according to the VXLAN tunnel, and sends the encapsulated VXLAN message to the convergence switch. Thus, only the BRAS network element selected by the controller will respond.

The preset selection rule may be to select a BRAS network element closest to the aggregation switch, and/or to select a BRAS network element with the smallest load, and specifically, the load of the BRAS network element may be obtained from network element information of the BRAS network element acquired from the controller.

The second method comprises the following steps: weak control mode of controller

After waiting for a certain Delay Time (PADO Delay Time), the BRAS network element generates a response message for the PPPoE first message, finds a corresponding VXLAN tunnel in a MAC address table corresponding to the VXLAN to which the response message belongs according to a destination MAC address of the response message, encapsulates the response message according to the VXLAN tunnel, and sends the VXLAN message obtained by encapsulation to the convergence switch. The delay time of each BRAS network element in the group 1 is configured and managed by the controller, and the controller can configure different delay times on different BRAS network elements in the group 1, so that the response time of different BRAS network elements is different.

In the second mode, the BRAS network elements in the packet 1 all respond, but the BRAS network elements respond in different orders because the BRAS network elements delay different times.

After receiving the VXLAN message encapsulated with the response message, the convergence switch decapsulates the VXLAN message to obtain the response message, determines an MAC address table corresponding to the VXLAN to which the VXLAN message belongs, learns a source MAC address of the response message, that is, adds an MAC entry in the MAC address table, where the MAC entry includes: and the source MAC address of the response message corresponds to the VXLAN tunnel receiving the VXLAN message. In addition, the convergence switch also finds the corresponding AC interface in the MAC address table according to the destination MAC address of the response message, and forwards the response message to the PPPoE client through the AC interface.

In the first mode, only the selected BRAS network element responds to the PPPoE first message sent by the PPPoE client, and after the response message is forwarded to the PPPoE client through the convergence switch, the PPPoE client establishes PPPoE connection with the selected BRAS network element. Subsequent messages sent by the PPPoE client comprise messages except the PPPoE first message in the PPPoE connection establishment process and data messages after the PPPoE connection is successfully established, the subsequent messages are unicast messages with the target MAC address being the MAC address of the selected BRAS network element, and the subsequent messages are forwarded to the selected BRAS network element. Therefore, the controller responds to the PPPoE first message sent by the PPPoE client by selecting one BRAS network element from the group 1, and the dispatching of the PPPoE data stream among the BRAS network elements in the same group is realized.

In the second mode, the controller configures different delay times for different BRAS network elements in the packet 1, so that the BRAS network element with the smallest delay time makes a response at the earliest time, and although response messages sent by each BRAS network element in the packet 1 are forwarded to the PPPoE client via the aggregation switch, the PPPoE client only selects the BRAS network element making the response at the earliest time to establish PPPoE connection. The subsequent messages sent by the PPPoE client comprise messages except the PPPoE first message in the PPPoE connection establishment process and data messages after the PPPoE connection establishment is successful, the subsequent messages are unicast messages of which the target MAC address is the MAC address of the BRAS network element which makes the response earliest, and the subsequent messages are forwarded to the BRAS network element which makes the response earliest. Therefore, the controller configures different delay times for different BRAS network elements in the same group, so that the response time of different BRAS network elements is different, and the PPPoE data stream is scheduled among the BRAS network elements in the same group.

In the process of processing the PPPoE first message and the response message, the convergence switch and the BRAS network element already learn the source MAC address, so that subsequent messages (unicast messages) between the PPPoE client and the BRAS network element can be directly subjected to table lookup and forwarded.

The process flow of the message forwarding in the PPPoE client → BRAS network element direction is as follows:

the PPPoE client sends a unicast message, and after receiving the unicast message, the aggregation switch executes a forwarding processing procedure shown in fig. 4:

step S301, after receiving a unicast message sent by a PPPoE client, a convergence switch determines an MAC address table corresponding to a VXLAN to which the unicast message belongs;

step S302, the convergence switch searches a corresponding VXLAN tunnel in the MAC address table according to the destination MAC address of the unicast message, encapsulates the unicast message according to the searched VXLAN tunnel, and sends the encapsulated VXLAN message to a BRAS network element of an opposite terminal.

After receiving the VXLAN packet, the BRAS network element decapsulates the VXLAN packet to obtain a unicast packet, and may perform corresponding processing on the unicast packet, for example, upload a protocol packet obtained by decapsulation to a protocol stack, and forward a data packet obtained by decapsulation to a public network.

The process flow of forwarding the message in BRAS network element → PPPoE client direction is as follows:

when the BRAS network element needs to send a unicast message, the BRAS network element determines an MAC address table corresponding to VXLAN to which the unicast message belongs, searches a corresponding VXLAN tunnel in the MAC address table according to a target MAC address corresponding to the unicast message, encapsulates the unicast message according to the searched VXLAN tunnel, and sends the VXLAN message obtained by encapsulation to the convergence switch. The unicast message to be sent may be, for example, a unicast message generated by the BRAS network element itself, or a unicast message received by the BRAS network element from a public network; the destination MAC address corresponding to the unicast message may be a destination MAC address carried in the unicast message, or may be an MAC address corresponding to a destination IP address carried in the unicast message.

After receiving the VXLAN message, the convergence switch decapsulates the VXLAN message, determines an MAC address table corresponding to the VXLAN to which the VXLAN message belongs, finds a corresponding AC interface in the MAC address table according to a destination MAC address of the unicast message, and forwards the unicast message to the PPPoE client through the AC interface.

In addition, the embodiment of the application also considers the problem of redundancy backup between BRAS network elements in the group 1. In the method of the above embodiment, no matter which of the first and second modes is adopted by the BRAS network element to respond, the PPPoE client establishes PPPoE connection with only one BRAS network element (for convenience of description, denoted as BRAS network element 1) and performs communication. Therefore, when the state of the BRAS network element 1 changes to unavailable (Down), for example, a link between the BRAS network element 1 and the convergence switch fails, or the BRAS network element 1 fails, the PPPoE client detects that the PPPoE connection is disconnected, and therefore the PPPoE client redials and sends a PPPoE first message for newly establishing the PPPoE connection; after receiving the PPPoE first packet, the convergence switch performs the processing of the steps S201 and S202 on the PPPoE first packet, so as to broadcast the PPPoE first packet to the BRAS network element in the packet 1.

When the mode I is adopted, because the BRAS network element 1 is unavailable, other BRAS network elements in an available state are decapsulated to obtain the PPPoE first message and then are reported to the controller, the controller reselects one BRAS network element (marked as the BRAS network element 2 for convenient description) from the BRAS network elements to respond, and the convergence switch learns the source MAC address of the response message after receiving the VXLAN message encapsulated with the response message, namely learns the MAC address of the BRAS network element 2 and forwards the response message to the PPPoE client; the PPPoE client establishes PPPoE connection with the BRAS network element 2 and communicates, and the destination MAC address of a unicast message subsequently sent by the PPPoE client is the MAC address of the BRAS network element 2.

When the second mode is adopted, because the BRAS network element 1 is unavailable, other BRAS network elements in an available state can respond, and the convergence switch can forward a response message to the PPPoE client after receiving the VXLAN message encapsulated with the response message; the PPPoE client establishes PPPoE connection with the BRAS network element (denoted as BRAS network element 2 for convenience of description) which responds earliest and performs communication, and the destination MAC address of the subsequently sent unicast message is the MAC address of the BRAS network element 2.

It can be seen from the above that, after the BRAS network element establishing PPPoE connection with the PPPoE client becomes unavailable, PPPoE connection can be established and communicated with the new BRAS network element, so that PPPoE data stream can be quickly switched to the new BRAS network element, and redundancy and backup of the BRAS network element in the same group are realized.

2. Authentication using IPoE

VRRP (Virtual Router Redundancy Protocol) is operated between BRAS network elements in the packet 1, wherein one BRAS network element serves as a master BRAS network element, and other BRAS network elements serve as slave BRAS network elements. The master BRAS network element and the slave BRAS network element have the same virtual MAC address for interacting with the IPoE client.

The working state of the opposite side is detected between the main BRAS network element and the auxiliary BRAS network element through periodic mutual heartbeat messages. Specifically, a main BRAS network element sends a heartbeat message to a convergence switch through a VXLAN tunnel, and the convergence switch forwards the heartbeat message to a slave BRAS network element through the VXLAN tunnel; and vice versa.

When an IPoE connection is to be established, an IPoE client first sends a first message in the IPoE connection establishment process, hereinafter referred to as an IPoE first message, and at this time, after receiving the IPoE first message, a convergence switch executes a processing flow for the IPoE first message, which is the same as the processing flow for the PPPoE first message in the PPPoE authentication embodiment. Therefore, the convergence switch will broadcast the VXLAN packet encapsulated with the IPoE first packet to the master BRAS network element and the slave BRAS network element, and learn the MAC address of the IPoE client.

After receiving a VXLAN message encapsulated with an IPoE first message, a master BRAS network element and a slave BRAS network element decapsulate the VXLAN message to obtain the IPoE first message, and then learn a source MAC address of the IPoE first message, so that an MAC table entry is added in an MAC address table corresponding to a VXLAN to which the VXLAN message belongs, wherein the MAC table entry comprises: the source MAC address of the IPoE first message corresponds to the VXLAN tunnel that received the VXLAN message, that is, the MAC address of the IPoE client corresponds to the VXLAN tunnel that received the VXLAN message. In addition, the main BRAS network element also generates a response message aiming at the IPoE first message, searches a corresponding VXLAN tunnel in an MAC address table corresponding to VXLAN to which the response message belongs according to a target MAC address of the response message, encapsulates the response message according to the VXLAN tunnel, and sends the VXLAN message obtained by encapsulation to the convergence switch.

Therefore, both the master BRAS network element and the slave BRAS network element learn the source MAC address of the IPoE first message, that is, the MAC address of the IPoE client, but only the master BRAS network element responds to the IPoE first message.

After receiving the VXLAN packet encapsulated with the response packet, the convergence switch learns the source MAC address (i.e., virtual MAC address) of the response packet, and forwards the response packet to the IPoE client. Because only the main BRAS network element responds, the IPoE client only establishes IPoE connection and communication with the main BRAS network element, the subsequent message sent by the IPoE client is a unicast message, and the destination MAC address is a virtual MAC address.

In the above processing process of the IPoE first message and the response message, the convergence switch and the main BRAS network element have already performed the learning of the source MAC address, so that the subsequent message (unicast message) between the IPoE client and the main BRAS network element can be directly forwarded by table lookup, wherein the subsequent message includes: the message except the IPoE first message in the IPoE connection establishment process, and the data message after the IPoE connection is successfully established.

Specifically, the processing flow of the message in the direction of IPoE client → primary BRAS network element is the same as the processing flow of the message in the direction of PPPoE client → BRAS network element in the foregoing PPPoE authentication embodiment; the processing flow of the message in the direction of the main BRAS network element → the IPoE client is the same as the processing flow of the message in the direction of the BRAS network element → the PPPoE client in the embodiment adopting the PPPoE authentication.

In addition, since the VRRP is operated between BRAS network elements within the packet 1, these BRAS network elements can be redundant and backup with each other.

Specifically, when a slave BRAS network element (for convenience of description, denoted as BRAS network element 2) detects that the state of a master BRAS network element (for convenience of description, denoted as BRAS network element 1) becomes unavailable (Down), for example, a link between BRAS network element 1 and a convergence switch is failed, so that a VXLAN tunnel between the two is unavailable, or the BRAS network element 1 is failed, the BRAS network element 2 is switched to the master BRAS network element, and a gratuitous ARP (address resolution protocol) message is sent to the convergence switch through the VXLAN tunnel, wherein a source MAC address of the gratuitous ARP message is a virtual MAC address; the aggregation switch receives a VXLAN message packaged with a free ARP message, then the free ARP message is obtained through de-packaging, then a matching table item is searched in an MAC address table corresponding to the VXLAN to which the VXLAN message belongs according to a source MAC address of the free ARP message, and when a VXLAN tunnel contained in the searched matching table item is different from a VXLAN tunnel receiving the VXLAN message, the VXLAN tunnel contained in the searched matching table item is updated to be the VXLAN tunnel receiving the VXLAN message. Therefore, the VXLAN tunnel of the convergence switch and the BRAS network element 1 of the outgoing interface of the matched table entry is updated, and the subsequent IPoE data flow is switched to the BRAS network element 2.

When the state of the BRAS network element 1 is recovered to be available and the back handover is needed, the BRAS network element 2 is switched to the slave BRAS network element again; BRAS network element 1 sends free ARP message to the convergence switch through VXLAN tunnel, the source MAC address of the free ARP message is the virtual MAC address; the aggregation switch receives a VXLAN message packaged with a free ARP message, then the free ARP message is obtained through de-packaging, then a matching table item is searched in an MAC address table corresponding to the VXLAN to which the VXLAN message belongs according to a source MAC address of the free ARP message, and when a VXLAN tunnel contained in the searched matching table item is different from a VXLAN tunnel receiving the VXLAN message, the VXLAN tunnel contained in the searched matching table item is updated to be the VXLAN tunnel receiving the VXLAN message. Therefore, the VXLAN tunnel of the convergence switch and the BRAS network element 1 is updated for the outgoing interface of the matched table entry from the VXLAN tunnel of the convergence switch and the BRAS network element 2, and the subsequent IPoE data flow is switched back to the BRAS network element 1.

It can be seen from the above that, after the primary BRAS network element becomes unavailable, the IPoE data stream can be quickly switched to the secondary BRAS network element, and after the primary BRAS network element is restored to be available, the IPoE data stream can also be quickly switched back to the primary BRAS network element, thereby realizing redundancy and backup of the BRAS network element in the same group.

The method of the embodiment of the application realizes the following technical effects:

the controller divides at least two BRAS network elements in the resource pool into a group in advance, then assigns a group for any aggregation switch, and establishes a VXLAN tunnel between the aggregation switch and each BRAS network element in the group to obtain a group of VXLAN tunnels, and an AC interface on the aggregation switch corresponds to the group of VXLAN tunnels.

When PPPoE authentication is adopted, after the aggregation switch receives a PPPoE first message of any client from the AC interface, the aggregation switch can send the PPPoE first message to each BRAS network element in the group through a VXLAN tunnel; and then, the controller selects a BRAS network element responding to the PPPoE first message according to a preset control mode, so that the convergence switch can send the PPPoE subsequent message to the selected BRAS network element through a VXLAN tunnel after receiving the PPPoE subsequent message of the client from the AC interface. Therefore, the PPPoE data stream of any client connected with the AC interface can be dispatched to the selected BRAS network element, and the dispatching of the PPPoE data stream among the BRAS network elements in the same group is realized.

When the state of the selected BRAS network element becomes unavailable, the client sends out the PPPoE first message again, and the controller can reselect the BRAS network element which responds to the PPPoE first message from other BRAS network elements in the available state according to a preset control mode, so that backup and redundancy among the BRAS network elements in the same group are realized, and reliability is improved.

In addition, when IPoE authentication is adopted, all BRAS network elements in the group operate VRRP, so that scheduling of IPoE data streams among the BRAS network elements in the same group and backup and redundancy among the BRAS network elements in the same group are realized, and reliability is improved.

For ease of understanding, the processing flow in the case of PPPoE authentication and the processing flow in the case of IPoE authentication are described below with reference to the actual networking architecture shown in fig. 1.

As shown in fig. 1, the controller divides BRAS network element 1 and BRAS network element 2 in the resource pool into the same group, referred to as group 1, and divides BRAS network element 3 and BRAS network element 4 in the resource pool into the same group, referred to as group 2. The controller establishes a VXLAN Tunnel between the HJSW1 and the BRAS network element 1 and BRAS network element 2 in packet 1, resulting in two VXLAN tunnels Tunnel1 and Tunnel2, which form a set of VXLAN tunnels.

AC interfaces AC1, Tunnel1 and Tunnel2 on HJSW1, and VXLAN1 correspond, where Tunnel1 is a VXLAN Tunnel between HJSW1 and BRAS network element 1, and Tunnel2 is a VXLAN Tunnel between HJSW1 and BRAS network element 2.

The client 1 (not shown in fig. 1) is connected to the AC1 of the HJSW1 through the OLT 1. The MAC address of client 1 is USER 1.

In a PPPoE application scenario, the MAC address of the BRAS network element 1 is vbars 1, and the MAC address of the BRAS network element 2 is vbars 2, and the following description will be given to the processing flow in the PPPoE application scenario by taking the BRAS network element making a response in the first manner as an example:

the client 1 sends a PPPoE first message, wherein the source MAC address of the PPPoE first message is USER1, and the destination MAC address is a broadcast MAC address; after receiving the PPPoE first message through the AC1, the HJSW1 determines the MAC address table corresponding to VXLAN1 to which the PPPoE first message belongs, learns the source MAC address USER1 of the PPPoE first message into the MAC address table, obtains the MAC table entry shown in line 2 of table 1-1, and encapsulates the PPPoE first message and sends out the encapsulated VXLAN message aiming at Tunnel1 and Tunnel2 corresponding to VXLAN1, thereby broadcasting the PPPoE first message to the BRAS network element 1 and the BRAS network element 2.

TABLE 1-1

MAC address	VXLAN ID	Outlet interface
			USER1	VXLAN1	AC1

After receiving the VXLAN message, the BRAS network element 1 decapsulates the VXLAN message to obtain a PPPoE header message, determines an MAC address table corresponding to VXLAN1 to which the VXLAN message belongs, learns a source MAC address USER1 of the PPPoE header message into the MAC address table to obtain an MAC entry as shown in row 2 of table 2-1, and reports the PPPoE header message to the controller.

Also, BRAS network element 2 performs the above operations, so as to learn the MAC table entry as shown in line 2 of table 3-1, and report the PPPoE header message to the controller.

TABLE 2-1

MAC address	VXLAN ID	Outlet interface
			USER1	VXLAN1	Tunnel1

TABLE 3-1

MAC address	VXLAN ID	Outlet interface
			USER1	VXLAN1	Tunnel2

After receiving the PPPoE first message reported by the BRAS network element 1 and the BRAS network element 2, the controller selects the BRAS network element 1 with the minimum load to send a response notice; after receiving the response notification, the BRAS network element 1 generates a response message for the PPPoE first message, the source MAC address of the response message is vbars 1, the destination MAC address is USER1, then, the corresponding outgoing interface is searched in the MAC address table shown in table 2-1 according to USER1, the Tunnel1 is found as a result, the response message is encapsulated, and the VXLAN message obtained by encapsulation is sent to HJSW 1.

After receiving the VXLAN message, the HJSW1 decapsulates the VXLAN message to obtain a response message therein, determines that the MAC address table corresponding to VXLAN1 to which the VXLAN message belongs is table 1-1, learns the source MAC address vbars 1 of the response message into the MAC address table shown in table 1-1, and refers to table 1-2, line 3, where table 1-1 is updated to table 1-2; and, the HJSW1 finds out that the corresponding outgoing interface is AC1 in the MAC address table shown in table 1-2 according to the destination MAC address USER1 of the response packet, and forwards the response packet to the client 1 through the AC 1.

Tables 1 to 2

MAC address	VXLAN ID	Outlet interface
			USER1	VXLAN1	AC1
vBRAS1	VXLAN1	Tunnel1

The PPPoE message subsequently sent by the client 1 is a unicast message, and the destination MAC address is vBRAS 1; the HJSW1 finds out that the corresponding outgoing interface is Tunnel1 in the MAC address table shown in table 1-2 according to the destination MAC address vbars 1 of the PPPoE message, so that the PPPoE message is encapsulated into a VXLAN message and then sent to the BRAS network element 1; after receiving the VXLAN message, BRAS network element 1 decapsulates the VXLAN message to obtain a PPPoE message, and performs corresponding processing on the PPPoE message.

When the BRAS network element 1 wants to send a PPPoE message to the client 1, according to a destination MAC address USER1 of the PPPoE message, finding out that a corresponding outgoing interface is Tunnel1 in a MAC address table shown in table 2-1, encapsulating the PPPoE message into a VXLAN message, and then sending the VXLAN message to HJSW 1; after receiving the VXLAN message, the HJSW1 decapsulates the VXLAN message to obtain a PPPoE message therein, and finds out that the corresponding outgoing interface is AC1 in the MAC address table shown in table 1-2 according to the destination MAC address USER1 of the PPPoE message, thereby sending the PPPoE message to the client 1 through the AC 1.

Therefore, through the above process, the client 1 establishes the PPPoE connection with the BRAS network element 1, and after the connection is successfully established, the service data communication is performed.

When the BRAS network element 1 has a fault, the client 1 detects that the PPPoE connection is disconnected, and retransmits a PPPoE first message, and the HJSW1 broadcasts the PPPoE first message to the BRAS network element 1 and the BRAS network element 2 after receiving the PPPoE first message. Because the BRAS network element 1 has a fault, only the BRAS network element 2 reports the PPPoE first message to the controller; the controller can only receive the PPPoE first message reported by the BRAS network element 2, therefore, the BRAS network element 2 is selected to send a response notice; after receiving the response notification, the BRAS network element 2 generates a response message aiming at the PPPoE first message, encapsulates the response message into a VXLAN message through a table look-up 3-1, and forwards the VXLAN message to the HJSW 1; after receiving the VXLAN message, the HJSW1 decapsulates the VXLAN message to obtain a response message therein, learns the source MAC address vbars 2 of the response message into the MAC address table shown in table 1-2 to obtain table 1-3, and the learned MAC table entry refers to the 4 th row in table 1-3, and in addition, the HJSW1 also forwards the response message to the client 1 through the AC1 by looking up the table 1-3. Subsequently, the destination MAC address of the PPPoE message sent by the client 1 is the MAC address vbars 2 of the BRAS network element 2, the client 1 establishes PPPoE connection with the BRAS network element 2, and after the connection is successfully established, service data communication is performed.

Tables 1 to 3

MAC address	VXLAN ID	Outlet interface
			USER1	VXLAN1	AC1
vBRAS1	VXLAN1	Tunnel1
			vBRAS2	VXLAN1	Tunnel2

The processing flow in the IPoE application scenario is as follows:

by automatic election, BRAS network element 1 is elected as a master BRAS network element, and BRAS network element 2 is elected as a slave BRAS network element. BRAS network element 1 and BRAS network element 2 have the same virtual MAC address vMAC.

The client 1 sends out an IPoE first message, wherein the source MAC address of the IPoE first message is USER1, and the destination MAC address is a broadcast MAC address; after receiving the IPoE header message through the AC1, the HJSW1 determines the MAC address table corresponding to the VXLAN1 to which the IPoE header message belongs, learns the source MAC address USER1 of the IPoE header message into the MAC address table to obtain the MAC table entry shown in the 2 nd row of table 1-1, and encapsulates the IPoE header message and sends the encapsulated VXLAN message to the Tunnel1 and Tunnel2 corresponding to the VXLAN1, so that the IPoE header message is broadcasted to the BRAS network element 1 and the BRAS network element 2.

After receiving the VXLAN message, BRAS network element 1 decapsulates the VXLAN message to obtain an IPoE first message, and learns a source MAC address USER1 of the IPoE first message to obtain an MAC entry shown in line 2 of table 2-1; and, since the BRAS network element 1 is a master BRAS network element, the BRAS network element 1 generates a response message for the IPoE first message, the source MAC address of the response message is vMAC, the destination MAC address is USER1, then, the corresponding egress interface is Tunnel1 found in the MAC address table shown in table 2-1 according to USER1, encapsulates the response message, and sends the encapsulated VXLAN message to HJSW 1.

After receiving the VXLAN message, BRAS network element 2 decapsulates the VXLAN message to obtain an IPoE header message therein, and learns a source MAC address USER1 of the IPoE header message to obtain an MAC entry as shown in line 2 of table 3-1.

After receiving the VXLAN message sent by the BRAS network element 1, the HJSW1 decapsulates the VXLAN message to obtain a response message therein, determines that an MAC address table corresponding to the VXLAN1 to which the response message belongs is table 1-1, learns the source MAC address vMAC of the response message into the MAC address table shown in table 1-1 to obtain table 1-4, wherein the learned MAC table entry refers to the 3 rd row of table 1-4; and, the HJSW1 finds out that the corresponding outgoing interface is AC1 in the MAC address table shown in tables 1-4 according to the destination MAC address USER1 of the response packet, and forwards the response packet to the client 1 through the AC 1.

Tables 1 to 4

MAC address	VXLAN ID	Outlet interface
			USER1	VXLAN1	AC1
vMAC	VXLAN1	Tunnel1

An IPoE message subsequently sent by the client 1 is a unicast message, and the destination MAC address is vMAC; the HJSW1 finds that the corresponding outgoing interface is Tunnel1 in the MAC address table shown in tables 1-4 according to the destination MAC address vMAC of the IPoE packet, so that the IPoE packet is encapsulated into a VXLAN packet and then sent to the BRAS network element 1; after receiving the VXLAN message, BRAS network element 1 decapsulates the VXLAN message to obtain the IPoE message, and performs corresponding processing on the IPoE message.

When the BRAS network element 1 wants to send an IPoE message to the client 1, according to a destination MAC address USER1 of the IPoE message, finding out that an interface is Tunnel1 in an MAC address table shown in table 2-1, encapsulating the IPoE message into a VXLAN message, and sending the VXLAN message to HJSW 1; after receiving the VXLAN message, the HJSW1 decapsulates the VXLAN message to obtain an IPoE message therein, and finds out that the corresponding outgoing interface is AC1 in the MAC address table shown in tables 1-4 according to the destination MAC address USER1 of the IPoE message, thereby sending the IPoE message to the client 1 through the AC 1.

Therefore, through the above process, the client 1 establishes an IPoE connection with the BRAS network element 1, and after the connection is successfully established, the service data is communicated.

When the BRAS network element 1 is in fault, the BRAS network element 2 detects that the state of the BRAS network element 1 is changed into Down, the BRAS network element 2 is switched to a main BRAS network element, a free ARP message is broadcasted, therefore, the free ARP message is sent to HJSW1 through Tunnel2, and the source MAC address of the free ARP message is vMAC.

After receiving the VXLAN message encapsulated with the gratuitous ARP message, the HJSW1 decapsulates the VXLAN message to obtain the gratuitous ARP message, then, according to the source MAC address vMAC of the gratuitous ARP message, searches for a matching table entry in tables 1-4 corresponding to the VXLAN1 to which the VXLAN message belongs, and as a result, finds out the MAC table entry in the 3 rd row of tables 1-4, and the VXLAN Tunnel1 included in the MAC table entry is different from the VXLAN Tunnel2 that received the VXLAN message, and updates the Tunnel1 included in the MAC table entry to Tunnel2, and at this time, tables 1-4 are updated to tables 1-5. Subsequently, the client 1 communicates with the BRAS network element 2.

Tables 1 to 5

MAC address	VXLAN ID	Outlet interface
			USER1	VXLAN1	AC1
vMAC	VXLAN1	Tunnel2

When the state of the BRAS network element 1 is recovered to be available (Up) and the back handover is needed, the BRAS network element 2 is switched to the slave BRAS network element again; BRAS net element 1 broadcasts free ARP message, thus will send to HJSW1 through Tunnel1, the source MAC address of the free ARP message is vMAC; after receiving the VXLAN message encapsulated with the gratuitous ARP message, the HJSW1 decapsulates the VXLAN message to obtain the gratuitous ARP message, then, according to the source MAC address vMAC of the gratuitous ARP message, searches for a matching table entry in tables 1-5 corresponding to the VXLAN1 to which the VXLAN message belongs, and as a result, finds out the MAC table entry shown in the 3 rd row of tables 1-5, and if the VXLAN Tunnel2 included in the MAC table entry is different from the VXLAN Tunnel1 that received the VXLAN message, updates the Tunnel2 included in the MAC table entry to Tunnel1, and updates tables 1-5 to tables 1-4. Subsequently, the client 1 communicates with the BRAS network element 1 again.

Corresponding to the foregoing embodiments of the traffic scheduling method, the present application also provides embodiments of a traffic scheduling apparatus.

The embodiment of the traffic scheduling device 60 of the present application can be applied to a controller. The above-mentioned embodiment of the traffic scheduling apparatus 60 may be implemented by software, or may be implemented by hardware, or a combination of hardware and software. In the case of software implementation, the device in a logical sense is formed by the processor 10 of the controller reading the corresponding computer program instructions in the non-volatile memory 50 into the memory 40 for execution. In terms of hardware, as shown in fig. 5, a hardware structure diagram of a controller of the traffic scheduling device according to the present application is shown, except for the processor 10, the internal bus 20, the network interface 30, the memory 40, and the nonvolatile memory 50 shown in fig. 5, the controller of the device in the embodiment may also include other hardware according to the actual function of the controller, which is not described again.

Referring to fig. 6, a traffic scheduling apparatus 60 according to an embodiment of the present application includes the following modules: a grouping module 601, a building module 602, and a selecting module 603, wherein:

a grouping module 601, configured to group BRAS network elements in a resource pool, where each group includes at least two BRAS network elements;

an establishing module 602, configured to assign a packet to a convergence switch, and establish a VXLAN tunnel between the convergence switch and each BRAS network element in the packet, so that the convergence switch sends a first client packet received from an AC interface to each BRAS network element in the packet through the VXLAN tunnel;

a selecting module 603, configured to select, according to a preset control mode, a BRAS network element that responds to the first message, so that the aggregation switch sends, through the VXLAN tunnel, the subsequent message of the client received from the AC interface to the selected BRAS network element.

The selecting module 603 includes: receiving unit, selection unit and transmitting unit, wherein:

a receiving unit, configured to receive a first message reported by each BRAS network element in the group;

a selecting unit, configured to select one BRAS network element from all BRAS network elements reporting a first message after the receiving unit receives the first message reported by each BRAS network element in the group;

and the sending unit is used for sending a response notice to the BRAS network element selected by the selecting unit so as to enable the selected BRAS network element to respond to the first message.

The selecting unit 603 is specifically configured to: selecting one BRAS network element from all the reported BRAS network elements according to a preset selection rule, wherein the preset selection rule comprises the following steps: and selecting the BRAS network element closest to the aggregation switch and/or selecting the BRAS network element with the minimum load.

Alternatively, the selecting module 603 includes: and a configuration unit, configured to configure delay time for each BRAS network element in the packet, and according to the corresponding delay time, the BRAS network element that responded to the first message earliest is the selected BRAS network element.

The VXLAN tunnels between the aggregation switch corresponding to the AC interface and all BRAS network elements in the packet correspond to the same VXLAN (for convenience of description, denoted as VXLAN 1).

Wherein, the establishing module 602 includes: interface configuration unit, creation unit and binding unit, wherein:

an interface configuration unit, configured to configure a Tunnel interface on the aggregation switch for each BRAS network element in the packet, and specify a source IP address of the Tunnel interface as an IP address of the aggregation switch and a destination IP address as an IP address of the BRAS network element; the system is also used for configuring a Tunnel interface on each BRAS network element, and the source IP address of the Tunnel interface is designated as the IP address of the BRAS network element, and the destination IP address is designated as the IP address of the convergence switch;

a creation unit to create a VSI on the aggregation switch, within which VXLAN1 is created; also for creating a VSI on each BRAS network element within the packet, within which VSI VXLAN1 is created;

a binding unit, configured to bind the AC interface, the VSI, and the Tunnel interface on the aggregation switch; and the method is also used for binding the VSI and the Tunnel interface on each BRAS network element.

The implementation process of the functions and actions of each unit in the above device is specifically described in the implementation process of the corresponding step in the above method, and is not described herein again.

For the device embodiments, since they substantially correspond to the method embodiments, reference may be made to the partial description of the method embodiments for relevant points. The above-described embodiments of the apparatus are merely illustrative, and the units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the modules can be selected according to actual needs to achieve the purpose of the scheme of the application. One of ordinary skill in the art can understand and implement it without inventive effort.

The above description is only exemplary of the present application and should not be taken as limiting the present application, as any modification, equivalent replacement, or improvement made within the spirit and principle of the present application should be included in the scope of protection of the present application.

Claims

1. A traffic scheduling method, characterized in that the method comprises:

grouping Broadband Remote Access Server (BRAS) network elements in a resource pool, wherein each group comprises at least two BRAS network elements;

assigning a group for a convergence switch, and establishing an extensible virtual local area network VXLAN tunnel between the convergence switch and each BRAS network element in the group, so that the convergence switch sends a client first message received from an access circuit AC interface to each BRAS network element in the group through the VXLAN tunnel;

and selecting a BRAS network element responding to the first message according to a preset control mode, so that the convergence switch sends the subsequent message of the client received from the AC interface to the selected BRAS network element through a VXLAN tunnel.

2. The method of claim 1, wherein selecting a BRAS network element that responds to the first packet according to a predetermined control mode comprises:

receiving the first message reported by each BRAS network element in the group;

selecting one BRAS network element from all BRAS network elements reporting the first message;

and sending a response notice to the selected BRAS network element so that the selected BRAS network element responds to the first message.

3. The method of claim 2, wherein the step of selecting a BRAS network element from among all reported BRAS network elements comprises:

selecting one BRAS network element from all reported BRAS network elements according to a preset selection rule, wherein the preset selection rule comprises the following steps: and selecting the BRAS network element closest to the aggregation switch and/or selecting the BRAS network element with the minimum load.

4. The method of claim 1, wherein selecting a BRAS network element that responds to the first packet according to a predetermined control mode comprises:

and configuring delay time for each BRAS network element in the group, and according to the corresponding delay time, the BRAS network element which responds to the first message at the earliest is the selected BRAS network element.

5. The method of claim 1, wherein VXLAN tunnels between the aggregation switch corresponding to the AC interface and all BRAS network elements within the packet correspond to a same VXLAN.

6. The method of claim 5, wherein the method of establishing a VXLAN tunnel between the aggregation switch and each BRAS network element within the packet comprises:

configuring a Tunnel interface on the convergence switch aiming at each BRAS network element, and designating a source IP address of the Tunnel interface as an IP address of the convergence switch and a destination IP address as an IP address of the BRAS network element; creating a virtual switch instance, VSI, on the aggregation switch, within which the VXLAN is created; binding the AC interface, the VSI, and the Tunnel interface;

for each BRAS network element, configuring a Tunnel interface on the BRAS network element, and designating a source IP address of the Tunnel interface as an IP address of the BRAS network element and a destination IP address as an IP address of the convergence switch; creating a VSI on the BRAS network element, and creating the VXLAN in the VSI; and binding the VSI and the Tunnel interface.

7. An apparatus for traffic scheduling, the apparatus comprising:

the device comprises a grouping module, a resource pool management module and a resource pool management module, wherein the grouping module is used for grouping Broadband Remote Access Server (BRAS) network elements in the resource pool, and each group comprises at least two BRAS network elements;

the establishing module is used for assigning a group for a convergence switch, and establishing an extensible virtual local area network VXLAN tunnel between the convergence switch and each BRAS network element in the group, so that the convergence switch sends a client first message received from an access circuit AC interface to each BRAS network element in the group through the VXLAN tunnel;

8. The apparatus of claim 7, wherein the selection module comprises:

a receiving unit, configured to receive the first packet reported by each BRAS network element in the packet;

a selecting unit, configured to select one BRAS network element from all BRAS network elements reporting a first message after the receiving unit receives the first message reported by each BRAS network element in the packet;

9. The apparatus according to claim 8, wherein the selection unit is specifically configured to:

10. The apparatus of claim 7, wherein the selection module comprises:

a configuration unit, configured to configure a delay time for each BRAS network element in the packet, and then, according to the corresponding delay time, the BRAS network element that responds to the first packet earliest is the selected BRAS network element.

11. The apparatus of claim 7, wherein VXLAN tunnels between the aggregation switch corresponding to the AC interface and all BRAS network elements within the packet correspond to a same VXLAN.

12. The apparatus of claim 11, wherein the establishing means comprises:

an interface configuration unit, configured to configure a Tunnel interface on the aggregation switch for each BRAS network element, and specify a source IP address of the Tunnel interface as an IP address of the aggregation switch and a destination IP address as an IP address of the BRAS network element; the system is further configured to configure a Tunnel interface on each BRAS network element, and specify that a source IP address of the Tunnel interface is an IP address of the BRAS network element and a destination IP address is an IP address of the aggregation switch;

a creating unit configured to create a virtual switch instance VSI on the aggregation switch, and create the VXLAN within the VSI; further configured to create a VSI on said each BRAS network element, said VXLAN being created within said VSI;

a binding unit, configured to bind, on the aggregation switch, the AC interface, the VSI, and the Tunnel interface; and is further configured to bind, on each BRAS network element, the VSI and the Tunnel interface.