WO2010139238A1

WO2010139238A1 - Method and device for implementing mac-forced forwarding

Info

Publication number: WO2010139238A1
Application number: PCT/CN2010/072924
Authority: WO
Inventors: 王金; 曹皖明
Original assignee: 中兴通讯股份有限公司
Priority date: 2009-06-03
Filing date: 2010-05-19
Publication date: 2010-12-09
Also published as: CN101577722A; CN101577722B

Abstract

A method for implementing MAC-forced forwarding is disclosed by the present invention. The method includes: the received message is determined to be an address resolution protocol (ARP) request message; after the physical interface connection is determined to be a user connection, a library of correspondences between users and gateways is queried on the basis of the IP address of the sender to obtain the IP address and MAC address of the gateway, and then an ARP response message is constructed and sent; or, after the physical interface connection is determined to be a gateway connection, the library of correspondences between users and gateways is queried on the basis of the destination IP address to obtain the IP address and MAC address of the user, and then the ARP response message is constructed and sent. A device for implementing MAC-forced forwarding is also disclosed by the present invention. The device includes a message processing module and an ARP proxy responding module. The device, on behalf of the gateway, directly replies with the ARP response message, reducing the number of ARP broadcast messages in the network.

Description

Method and device for implementing forced MAC forwarding function

The present invention relates to the field of Ethernet data communications, and in particular, to a method and apparatus for implementing a MAC-Forced Forwarding (MFF) function. Background technique

It is well known that communication between hosts in the same broadcast domain does not require a gateway to pass through the Layer 2 forwarding function of the access device. This approach makes communication within the broadcast domain more open and efficient, while reducing the burden on the gateway. However, if user access needs to be controlled, this method cannot meet the demand. At the same time, in this mode, the gateway cannot monitor the communication traffic between hosts in the broadcast domain, and the security of the network cannot be better guaranteed.

To meet the requirements for controlling user access, you can perform Layer 2 isolation on hosts in the same broadcast domain. A common method of user isolation is to divide a virtual local area network (VLAN) on an access device. However, when there are many users who need to isolate Layer 2, this method will occupy a large amount of VLAN resources. At the same time, in order to implement Layer 3 interworking between clients, different Internet Protocol (IP) needs to be planned for each VLAN. The network segment and the IP address of the VLAN interface are configured. The excessive division of VLANs reduces the efficiency of IP address allocation.

RFC4562 "MAC-Forced Forwarding: A Method for Subscriber Separation on an Ethernet Access Network" proposes a solution. In this solution, the access device intercepts the address resolution protocol (ARP) request of the user, and responds to the ARP reply message of the Media Access Control (MAC) address of the gateway through the ARP pickup mechanism. In this way, the user can be forced to send all traffic (including traffic within the same subnet) to the gateway.

However, RFC4562 has the following disadvantages: (1) There is no ring described in the static configuration IP address. In the context, an Ethernet access node (EAN) automatically obtains a user IP address, a MAC address, a virtual local area network (VLAN), and a corresponding access router (AR); (2) For the ARP request packet sent by the AR, the EAN forwards directly. Summary of the invention

The object of the present invention is to provide a method and apparatus for implementing a mandatory MAC forwarding function, which is used to solve the problem that the static configuration IP address cannot automatically obtain the correspondence between the user and the gateway and cannot be minimized on the network. Defects in ARP broadcast messages.

In order to achieve the above object, the method for implementing the mandatory MAC forwarding function provided by the present invention includes the following steps:

Determining that the received packet is an address resolution protocol request packet;

After determining that the connection attribute of the physical interface that receives the address resolution protocol request message is a user connection, the user and the gateway correspondence database are queried according to the sender IP address in the address resolution protocol request, and the sender is obtained. The IP address of the gateway corresponding to the IP address and the MAC address of the gateway;

And constructing and sending an address resolution protocol response ^^ according to the IP address and MAC address of the gateway and the address resolution protocol request; or

After determining that the connection attribute of the physical interface that receives the address resolution protocol request message is a gateway connection, query the user and the gateway correspondence database according to the destination IP address in the address resolution protocol request message, and obtain the IP address of the user and the user. MAC address;

And according to the IP address and MAC address of the user and the address resolution protocol request, and the address resolution protocol is sent and sent.

The user and gateway correspondence library is pre-established by the following process:

After receiving the address resolution protocol request message or the response message, the sender IP address and the sender header address creation protocol in the address resolution protocol request message or the response message are obtained. Determining an IP address of the gateway configured in the VLAN according to the VLAN identifier in the address resolution protocol request packet or the response packet; determining that the sender IP address is different from the IP address of the gateway; And associating the address resolution protocol entry with the IP address of the gateway to establish a user and gateway correspondence library.

After the connection attribute of the physical interface that receives the address resolution protocol request message is determined to be a user connection, and the sender IP address is queried according to the sender IP address in the address resolution protocol request message, Before obtaining the IP address of the gateway corresponding to the sender IP address and the MAC address corresponding to the IP address of the gateway, the method further includes:

After determining that the destination IP address in the address resolution protocol request packet is a user, querying the user and the gateway correspondence database to confirm that the destination user is online; or determining that the destination IP address in the address resolution protocol request is the Gateway under VLAN configuration.

The obtaining the MAC address corresponding to the IP address of the gateway is specifically: querying the address resolution protocol entry according to the IP address of the gateway to obtain the MAC address of the gateway.

And constructing and sending an address resolution protocol response according to the IP address and the MAC address of the gateway and the address resolution protocol request message.

The IP address and the MAC address of the gateway are respectively used as the sender IP address and the sender header of the address resolution protocol to be constructed; and the address IP address of the sender in the address resolution protocol request message is The sender header is the destination IP address and destination header of the address resolution protocol response message to be constructed; and the address resolution protocol response constructed is sent.

After the connection attribute of the physical interface that receives the address resolution protocol request message is determined to be a gateway connection, the user and the gateway correspondence database are queried according to the destination IP address in the address resolution protocol request message, and the user is acquired. Before the IP address and the MAC address of the user, the method further includes: determining that the sender address in the address resolution protocol request message is an IP address of the gateway, and the destination IP address is the user IP address. The obtaining the IP address of the user and the MAC address of the user are: the destination IP address is the user IP address, and the IP address of the user queries the MAC address of the user in the user and the gateway correspondence database. .

The constructing and sending the address resolution protocol response according to the user's IP address and MAC address and the address resolution protocol request include: using the user's IP address and MAC address as the desired structure Determining a sender IP address and a sender header of the address resolution protocol response message; using the sender IP address and the sender header in the address resolution protocol request as the destination IP address of the address resolution protocol response message to be constructed And the destination header; and the constructed address resolution protocol response message is sent.

When the user and the gateway correspondence database do not record the IP address of the destination user in the address resolution protocol request message; the IP address and the MAC address of the gateway are respectively used as the address resolution protocol request to be constructed. a sender IP address and a sender header, the destination IP address being the destination IP address of the address resolution protocol request message to be constructed, and constructing the address resolution protocol request message to be constructed to trigger the user Learning with the gateway correspondence library.

When the user and the gateway correspondence library do not record the sender IP address in the address resolution protocol request message; the IP address and the MAC address of the gateway are respectively used as address resolution protocol requests to be constructed. a sender IP address and a sender header, the sender IP address being the destination IP address of the address resolution protocol request message to be constructed, and constructing the address resolution protocol request message to be constructed to trigger the user Learning with the gateway correspondence library.

The connection properties of the physical interface are set through a user interface.

The device for implementing the mandatory MAC forwarding function provided by the present invention includes:

a packet processing module, configured to: forward the address resolution protocol request packet received by the physical interface of the access node; An address resolution protocol proxy module, configured to be connected to the packet processing module, configured to determine, after the connection property of the physical interface that receives the address resolution protocol request packet is a user connection, according to the sender in the address resolution protocol request Querying the user and the gateway correspondence database of the IP address, obtaining the IP address of the gateway corresponding to the sender IP address and the MAC address corresponding to the IP address of the gateway; and parsing according to the IP address and MAC address of the gateway and the address The protocol request message is configured to send and send an address resolution protocol response message; or after determining that the connection attribute of the physical interface receiving the address resolution protocol request message is a gateway connection, requesting the purpose in the ^^ text according to the address resolution protocol The party IP address queries the user and the gateway correspondence database, and obtains the IP address of the user and the MAC address corresponding to the IP address of the user; and constructs and sends according to the IP address and MAC address of the user and the address resolution protocol request message. Address Resolution Protocol response message.

The device for implementing the mandatory MAC forwarding function further includes: a forced MAC forwarding learning module, configured to: after receiving the address resolution protocol request message or the response message, obtain the sender IP address and the sending address in the address resolution protocol request message or the response message An address resolution protocol entry is created by the first header; the IP address of the gateway configured in the VLAN is searched according to the VLAN identifier in the address resolution protocol request packet or the response packet; and the sender IP address and the IP address of the gateway are determined. The addresses are different; the address resolution protocol entry and the IP address of the gateway are associated to establish a user and gateway correspondence library.

Therefore, the method and the device for implementing the mandatory MAC forwarding function of the present invention automatically acquire the manner of the user-to-gateway correspondence required to implement the MFF function by intercepting and analyzing the ARP packet. In addition, the EAN does not forward the gateway. The ARP request packet, but the ARP reply packet that the access device directly responds to the user's MAC address, can reduce the number of ARP broadcast packets on the network. DRAWINGS

1 is a block diagram of a device for implementing a forced MAC forwarding function according to the present invention; 2 is a learning process of a correspondence between a user and a gateway according to the present invention;

3 is a flowchart of Embodiment 1 of a method for implementing a mandatory MAC forwarding function according to the present invention; FIG. 4 is a content of a record of an ARP entry according to the present invention;

FIG. 5 is a schematic diagram of a user and gateway correspondence library according to the present invention; FIG.

FIG. 6 is a flowchart of Embodiment 2 of a method for implementing a mandatory MAC forwarding function according to the present invention. detailed description

The technical solutions of the embodiments of the present invention are further described in detail below with reference to the accompanying drawings and embodiments.

As shown in FIG. 1 , it is a block diagram of a device for implementing a forced MAC forwarding function. The device implements the ARP request packet not to be forwarded, but instead responds, thereby reducing ARP broadcast packets in the network. The device includes:

The packet processing module 10 is configured to determine that the address resolution protocol request packet received on the physical interface of the access node is not forwarded, but is forwarded;

An address resolution protocol (ARP) proxy module 20 is connected to the packet processing module 10, and is configured to: after determining that the connection property of the physical interface that receives the ARP request packet is a user connection, according to the sender in the ARP request packet The IP address query user and gateway correspondence library 50 obtains the IP address of the gateway corresponding to the sender IP address and the MAC address corresponding to the IP address of the gateway; according to the IP address and MAC address of the gateway and the ARP request ^艮 , , , 构造构造构造构造构造构造构造构造构造构造构造构造构造构造构造构造构造构造构造构造构造构造构造构造构造构造构造构造构造构造构造构造构造构造构造构造构造构造构造构造构造构造构造构造构造构造构造构造构造构造构造The IP address and the MAC address corresponding to the user's IP address; construct and send an address resolution protocol response according to the user's IP address and MAC address and the ARP request.

The specific pickup process of the module 20 can be referred to the detailed description in FIG. 3 and FIG. 6. As shown in FIG. 1, the apparatus for implementing the mandatory MAC forwarding function further includes: The mandatory MAC forwarding learning module 30 is configured to obtain an ARP request packet or a response packet, and obtain an ARP request packet or a sender IP address of the response packet and a sender header to create an address resolution protocol entry (the address resolution protocol entry) The IP address of the gateway configured in the VLAN is searched according to the VLAN identifier in the ARP request packet or the response packet. The IP address of the sender and the gateway are determined. The IP address is different; the address resolution protocol entry and the IP address of the gateway are associated to establish a user and gateway correspondence library 50.

The forced MAC forwarding learning module 30 performs a learning process on all ARP request messages at any time to establish a user and gateway correspondence library.

The Address Resolution Protocol Pickup Module also has the following functions to trigger the learning of the user and gateway correspondence libraries. When the user and the gateway correspondence database are searched, the IP address of the sender in the ARP request packet is not found (that is, the user IP address of the user and the gateway correspondence database that is not indexed by the sender IP address is recorded in the library). At this point, the address resolution protocol pickup module will construct a new ARP request message to trigger the learning of the user and gateway correspondence database. The IP address and MAC address of the gateway are respectively used as the sender IP address and sender header of the ARP request packet to be constructed. The IP address of the sender of the original ARP request packet is the destination IP address of the ARP request packet to be constructed. This is built into the ARP request to be constructed.

If the IP address of the destination user is not found in the user IP address index in the user and gateway mapping database, the address resolution protocol pickup module will also construct a new ARP request packet to trigger the user and gateway correspondence database. Learning. The IP address and MAC address of the gateway are respectively used as the sender IP address and the sender's header of the ARP request packet to be constructed. The destination IP address of the original ARP packet is the destination IP address of the ARP request text to be constructed. ARP request message to trigger the learning of the user and gateway correspondence library. The constructed request message will be broadcast in the VLAN and will not be learned. Subsequent learning is performed based on the received ARP response message from the user. The address resolution protocol pickup module 20 and the forced MAC forwarding learning module 30 may be included in one module, namely the address resolution protocol module 60.

The apparatus for implementing the mandatory MAC forwarding function may further include a user interface 70, by which the network administrator can set whether the connection attribute of the physical interface is a user connection or a gateway connection, and configure an IP address of the gateway under the VLAN, and view the User and gateway relationship library 50.

In order to maintain the user and the gateway correspondence library, the device for implementing the forced MAC forwarding function further includes a user and gateway correspondence database organization and maintenance module 40, and is connected with the mandatory MAC forwarding learning module 30 and the ARP pickup module 20, and the user information is The IP address, MAC address, and VLAN ID of the corresponding gateway are organized into a table to provide interfaces for adding, deleting, updating, and querying entries.

An embodiment of a method for implementing a forced MAC forwarding function based on a device implementing a mandatory MAC forwarding function will be described below to better understand the function of the device. The device that implements the forced MAC forwarding function is placed on an access node (Access Node, AN) between the customer premises network and the tandem network.

In the present invention, first, the network administrator statically specifies that the connection attribute of the physical interface is a gateway connection or a user connection through the user interface. Therefore, when the AN receives the ARP request packet, it can query the attributes of the physical interface, and can determine whether the physical interface that receives the ARP request message is the user or the gateway, so that the ARP request packet is sent from the user. Still a gateway.

The user and the gateway correspondence library are obtained through the learning mechanism, so that the corresponding relationship between the user and the gateway cannot be automatically obtained in the prior art. The mandatory MAC forwarding learning module 30 in the mandatory MAC forwarding function device queries the IP address of the corresponding gateway according to the VLAN identifier of the ARP packet (for example, the ARP request packet and the ARP response packet) (there is only one gateway in each VLAN. Configured by the network administrator). Then, the user information (user IP address, MAC address, and VLAN ID) recorded by the ARP entry is associated with the gateway and added to the user and the network. In the relationship library. The ARP entry is a mandatory MAC forwarding learning module that parses the sender IP address and the sender header (sender MAC address) from the ARP request message or the response. Then the ARP entry is created and added to the ARP cache. The created ARP entry includes sending The party IP, the sender MAC address, and the VLAN identifier. The forced MAC forwarding learning module completes the automatic learning and creation of the correspondence between the user and the gateway.

The ARP entry is added to the cache. The ARP entry includes the sender (user or gateway) MAC address, the sender (user or gateway) IP address, and the VLAN ID. The contents of the record of the ARP entry are shown in Figure 4.

In the user and gateway correspondence library, the user and gateway correspondence is a data table indexed by the user IP address, and the data table includes the user IP address, the user MAC address, the VLAN identifier, and the IP of the VLAN-related gateway. The address is used to query the IP address of the gateway configured in the VLAN to which the user IP address is indexed, and then obtain the MAC address of the gateway by obtaining the ARP entry corresponding to the gateway from the cache according to the IP address of the gateway. address. A schematic diagram of the user and gateway correspondence library is shown in FIG. 5.

The process is a learning process of the correspondence between the user and the gateway of the present invention. As shown in FIG. 2, the process includes the following steps. Referring to FIG. 5, the schematic diagram of the correspondence between the user and the gateway is as follows: The interface connecting the user and the interface connecting the gateway will send all received ARP packets (including requests and responses) to the address resolution pickup module for processing.

Step 201: After receiving the address resolution protocol request message or the response message, obtain the address resolution protocol request>3⁄4 text or the sender IP address in the response message and the sender header (ie, the sender MAC address) to create an ARP entry to be added. In the ARP cache, the user information recorded by the ARP entry has the sender's IP address, MAC address, and VLAN ID (the ARP entry may be gateway or user's.)

Step 202: Request, according to the address resolution protocol, a VLAN in a request packet or a response packet. Identifying an IP address of a gateway configured in the VLAN;

Step 203: Determine that the sender IP address is different from the IP address of the gateway, so as to prevent the sender from being a gateway configured in the VLAN.

Step 204: Associate the address resolution protocol entry and the IP address of the gateway to establish a user and gateway correspondence database.

Organizing and maintaining the user interface (IP address, MAC address, VLAN ID) and the IP address of the corresponding gateway into a single table, providing an interface for adding, deleting, updating, and querying the entries, thereby Add to the user and gateway correspondence library.

As shown in FIG. 3, it is a flowchart of Embodiment 1 of a method for implementing a mandatory MAC forwarding function according to the present invention. First, the network administrator statically specifies the physical receiving interface through the user interface to connect to the gateway or the user. For example, the user who specifies the receiving interface is connected. Therefore, it is assumed that the packet received on the physical interface of the AN in the first embodiment is an Address Resolution Protocol Request (ARP) packet; and the physical interface attribute is a connected user. That is, the device first judges the received packet, and does not forward the ARP request packet, but performs the process of implementing the mandatory MAC forwarding function.

As shown in FIG. 3, the physical receiving interface is connected to the user, and the process includes the following steps: Step 301: Determine that the currently received packet is an ARP request packet.

Step 302: Determine that the attribute of the physical interface that receives the ARP request packet is set to be the connected user (that is, the user host).

Step 303: Determine whether the destination IP address in the ARP request packet is a gateway. The gateway refers to a VLAN gateway, and searches for the IP address of the gateway configured in the VLAN according to the VLAN identifier, and then determines whether the IP address is the gateway associated with the VLAN. IP address, if it is judged as a gateway, otherwise it is judged as a user;);

Step 304: If the destination IP address is not the gateway address but the user IP address, query the user and the gateway correspondence database to confirm that the destination user is online (whether there is a record); If you are on the line, you will not pick up the traffic to block the traffic and prevent the gateway from being attacked.

Step 305: Query the user and the gateway correspondence database according to the sender IP address in the ARP request, and obtain the IP address of the VLAN-related gateway corresponding to the sender IP address (that is, the IP address of the user connected to the physical interface); In the user and gateway correspondence table, the sender IP address is in the column indexed by the user IP address, and the record of the same IP is found, and then the IP address of the gateway is found;

Step 306: Query an ARP cache according to the IP address of the gateway, and obtain a MAC address corresponding to the IP address from the ARP entry.

Step 307: Construct and send an ARP response packet according to the IP address and the MAC address of the gateway and the ARP request, and the step includes:

Step 3071: The IP address and the MAC address of the gateway are respectively used as the sender IP address and the sender header of the ARP reply message to be constructed;

Step 3072: The sender IP address and the sender header in the ARP request message are used as the destination IP address and destination header of the ARP response message to be constructed; and

Step 3073: Send the constructed ARP response packet to the user.

The foregoing process describes the case where the destination IP address in the ARP request message is the user, and in step 303, the destination IP address of the ARP request packet is the IP address of the gateway associated with the VLAN, as shown in FIG. 3, that is, After step 303, step 305 to step 307 are directly executed.

If the IP address of the sender in the ARP request message is not found when searching the user and the gateway correspondence library in the above step 305 (that is, the user IP address in the user and the gateway correspondence database that is not indexed by the sender IP address is recorded in the library. Medium), at this point, the address resolution protocol pickup module will construct a new ARP request message to trigger the learning of the user and gateway correspondence database. The IP address and MAC address of the gateway are respectively used as the sender IP address and sender header of the ARP request packet to be constructed. The IP address of the sender of the original ARP request packet is the destination IP address of the ARP request packet to be constructed. This is constructed as an ARP request message to be constructed. In addition to the above, a new ARP request message is triggered to trigger the user and gateway correspondence library. When the user IP address index in the user and gateway correspondence database is not found in step 304, the IP address of the destination user is not found. At this time, the address resolution protocol pickup module will also construct a new ARP request message to trigger the learning of the user and gateway correspondence database. The IP address and the MAC address of the gateway are respectively used as the sender IP address and the sender's header of the ARP request packet to be constructed. The destination IP address of the original ARP packet is the destination IP address of the ARP request packet to be constructed. A new ARP request message to trigger the learning of the user and gateway correspondence library. The constructed request message will be broadcast in the VLAN and will not be learned. Subsequent learning is performed based on the received ARP response message from the user.

FIG. 6 is a flow chart of Embodiment 2 of a method for implementing a forced MAC forwarding function according to the present invention. First, the network administrator statically specifies the physical receiving interface through the user interface to connect to the gateway or the user. For example, the designated receiving interface is connected to the gateway. Therefore, it is assumed that the message received on the physical interface of the AN in the first embodiment is an Address Resolution Protocol Request (ARP) message; and the physical interface attribute is a connection gateway. That is, in the device, the received packet is first judged, and the ARP request packet from the gateway is not forwarded, but the process of implementing the mandatory MAC forwarding function is performed.

As shown in Figure 6, the physical receiving interface is connected to the gateway. The process of implementing the MAC function forwarding method includes the following steps:

Step 601: Determine that the currently received packet is an ARP request packet.

Step 602: Determine that the attribute of the physical interface that receives the ARP request message is set to be the connection gateway. Step 603: Determine whether the IP address of the sender in the ARP request message is an IP address of the gateway configured by the VLAN. The IP address of the gateway is based on the VLAN identifier. Find the IP address of the gateway configured in the VLAN.

Step 604, if not, discarding the ARP request packet;

Step 605, if yes, then determine whether the destination address of the ARP request packet is a VLAN. Configure the IP address of the gateway.

Step 606, if yes, discarding the ARP request packet;

Step 607: If not, query the user and the gateway correspondence database according to the destination IP address in the ARP request packet (the destination IP address is the user IP address), and obtain the IP address of the user and the MAC address of the user; The IP address of the user queries the correspondence database of the user and the gateway, and obtains the MAC address of the user;

Step 608: Construct and send an ARP response packet according to the IP address and the MAC address of the user and the ARP request, and the step includes:

Step 6081: The IP address and the MAC address of the user are respectively used as the sender IP address and the sender header of the ARP reply message to be constructed;

Step 6082: The sender IP address and the sender header in the ARP request message are used as the destination IP address and destination header of the ARP response message to be constructed; and

Step 6083: Send the constructed ARP reply packet to the gateway, where the gateway is also a gateway configured in the VLAN.

Through the process described in Embodiment 1 and Embodiment 1, the method for implementing the mandatory MAC forwarding function is implemented by the present invention, and after the AN receives the ARP request packet, the AN does not forward the packet, but directly responds, and establishes The automatic learning mechanism of the user-to-gateway relationship automatically obtains the correspondence between the user and the gateway, thus reducing the number of ARP broadcast packets on the network.

In the automatic learning of the correspondence between the user and the gateway, the learning mechanism may be triggered by establishing a new ARP request message, and the trigger may be used to query the user and the gateway correspondence database during the entire pickup process, when in the relational library. When there is an unrecorded user IP address, a new ARP request can be established to trigger the learning mechanism. The invention implements ARP pickup, receives the user's ARP request message, responds with the gateway's MAC address, and receives the ARP request message of the gateway, and then responds with the user's MAC address.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention and are not limited thereto. The present invention has been described in detail with reference to the preferred embodiments thereof, and it is understood that the invention may be modified, modified or equivalently substituted without departing from the spirit and scope of the invention.

Claims

Claim

A method for implementing a mandatory MAC forwarding function, the method comprising: determining that the received packet is an address resolution protocol request packet;

After determining that the connection attribute of the physical interface that receives the address resolution protocol request message is a user connection, querying the user and the gateway correspondence database according to the sender Internet Protocol (IP) address in the address resolution protocol request message, and obtaining the The IP address of the gateway corresponding to the sender IP address and the media access control (MAC) address of the gateway;

The method for implementing the mandatory MAC forwarding function according to claim 1, wherein the user and gateway correspondence database is pre-established by the following process:

After receiving the address resolution protocol request message or the response message, obtaining the address resolution protocol request message or the sender IP address in the response message and the sender header to create an address resolution protocol entry;

And searching for an IP address of the gateway configured in the VLAN according to the virtual local area network (VLAN) identifier in the address resolution protocol request packet or the response packet;

Determining that the sender IP address is different from the gateway IP address; and

The address resolution protocol entry and the IP address of the gateway are associated to establish a user and gateway correspondence library.

3. A method of implementing a mandatory MAC forwarding function as claimed in claim 2, characterized in that After the connection attribute of the physical interface that receives the address resolution protocol request message is determined to be a user connection, and the sender IP address is queried according to the sender IP address in the address resolution protocol request message, Before obtaining the IP address of the gateway corresponding to the sender IP address and the MAC address corresponding to the IP address of the gateway, the method further includes:

After determining that the destination IP address in the address resolution protocol request packet is a user, querying the user and the gateway correspondence database to confirm that the destination user is online; or a gateway.

The method for implementing the mandatory MAC forwarding function according to claim 3, wherein the obtaining the MAC address corresponding to the IP address of the gateway is specifically:

Querying the address resolution protocol entry according to the IP address of the gateway to obtain a MAC address of the gateway.

The method for implementing the mandatory MAC forwarding function according to claim 4, wherein the requesting and sending an address resolution protocol according to the IP address and MAC address of the gateway and the address resolution protocol request The response ^ text includes:

The IP address and the MAC address of the gateway are respectively used as the sender IP address and the sender header of the address resolution protocol to be configured;

And sending, by the sender IP address and the sender header in the address resolution protocol request message, a destination IP address and a destination header of the address resolution protocol response message to be constructed; and

The constructed address resolution protocol response message is sent.

The method for implementing the mandatory MAC forwarding function according to claim 2, wherein the determining that the connection attribute of the physical interface that receives the address resolution protocol request message is a gateway connection, and The destination IP address in the address resolution protocol request packet is used to query the user and gateway correspondence database. Before obtaining the IP address of the user and the MAC address of the user, the method further includes: Determining that the sender address in the address resolution protocol request message is an IP address of the gateway, and the destination IP address is the user IP address.

The method for implementing the mandatory MAC forwarding function according to claim 6, wherein the acquiring the IP address of the user and the MAC address of the user are specifically:

The destination IP address is the user IP address, and the MAC address of the user in the user and gateway correspondence database is queried according to the IP address of the user.

The method for implementing the mandatory MAC forwarding function according to claim 7, wherein the requesting and constructing an address resolution protocol response according to the IP address and MAC address of the user and the address resolution protocol ^Text includes:

The IP address and the MAC address of the user are respectively used as the sender IP address and the sender header of the address resolution protocol to be configured;

The constructed address resolution protocol response message is sent.

The method for implementing the mandatory MAC forwarding function according to claim 3, wherein when the user and the gateway correspondence database do not record the IP address of the destination user in the address resolution protocol request message; The IP address and the MAC address of the gateway are respectively used as the sender IP address and the sender header of the address resolution protocol request to be constructed, and the destination IP address is the destination of the address resolution protocol request message to be constructed. The IP address is constructed into the address resolution protocol request message to be constructed to trigger the learning of the user and the gateway correspondence database.

The method for implementing the mandatory MAC forwarding function according to claim 3, wherein when the user and the gateway correspondence database do not record the sender IP address in the address resolution protocol request message; The IP address and the MAC address of the gateway are respectively used as the sender IP address and the sender header of the address resolution protocol request to be constructed, and the sender IP address is the destination of the address resolution protocol request message to be constructed. IP address, constructed into the desired structure The established address resolution protocol requests >3⁄4 text to trigger the learning of the user and gateway correspondence library.

The method for implementing a mandatory MAC forwarding function according to claim 1, wherein the connection attribute of the physical interface is set through a user interface.

An apparatus for implementing a mandatory MAC forwarding function, comprising: a packet processing module, configured to: forward an address resolution protocol request message received by a physical interface of an access node;

An address resolution protocol proxy module, configured to be connected to the packet processing module, configured to determine, after the connection property of the physical interface that receives the address resolution protocol request packet is a user connection, according to the sender in the address resolution protocol request Querying the user and the gateway correspondence database of the IP address, obtaining the IP address of the gateway corresponding to the sender IP address and the MAC address corresponding to the IP address of the gateway; and parsing according to the IP address and MAC address of the gateway and the address The protocol request message is configured to send and send an address resolution protocol response message; or after determining that the connection attribute of the physical interface receiving the address resolution protocol request message is a gateway connection, requesting the purpose in the ^^ text according to the address resolution protocol The party IP address queries the user and the gateway correspondence database, and obtains the IP address of the user and the MAC address corresponding to the IP address of the user; and constructs and sends according to the IP address and MAC address of the user and the address resolution protocol request message. Address Resolution Protocol response message.

13. The apparatus for implementing a mandatory MAC forwarding function according to claim 12, further comprising:

The mandatory MAC forwarding learning module is configured to: after receiving the address resolution protocol request packet or the response packet, obtain the sender IP address and the sender header to create an address resolution protocol entry in the address resolution protocol request packet or the response packet. And determining, according to the VLAN identifier in the address resolution protocol request packet or the response packet, an IP address of the gateway configured in the VLAN; determining that the sender IP address is different from the IP address of the gateway; The protocol entry and the IP address association of the gateway are resolved to establish a user and gateway correspondence library.