CN105553810A - Method and device for forwarding special line service packet - Google Patents

Abstract

Embodiments of the present invention provide a method and device for forwarding private line service messages, which relate to the communication field, without adding or modifying configurations of existing IP bearer networks, so as to realize the transmission of private line service messages in the network domain. Including: the first access gateway obtains the private line service message; determines the general route to encapsulate the GRE tunnel, the source IP address of the GRE tunnel is the IP address of the first access gateway, and the destination IP address of the GRE tunnel is the IP address of the second access gateway address; obtain the PW label; perform MPLS encapsulation to obtain MPLS-encapsulated private line service packets; perform GRE encapsulation on MPLS-encapsulated private line service packets to obtain GRE-encapsulated private line service packets; send GRE-encapsulated private line service packets to the second access gateway through the GRE tunnel business message. It is used to transmit leased line service packets.

Description

Method and device for forwarding private line service message

technical field

The invention relates to the communication field, in particular to a method and device for forwarding private line service messages.

Background technique

Private line service refers to the provision of dedicated channels between two points or between multiple points to transmit business messages such as voice, data, audio or video with high traffic volume. The leased line service is one of the main services carried on the network deployed by the operator. Usually, a city is used as a network domain, and Multi-Protocol Label Switching (English abbreviation: Multi-Protocol Label Switching, English abbreviation: MPLS) virtual private network (English full name: VirtualPrivateNetwork, English abbreviation: VPN), which provides a dedicated channel for private line business messages. The network configuration will become more and more complex with the increase of leased line service packets.

When private line service packets need to be transmitted across two or more different network domains, Option A can be used to decapsulate the private line services one by one at the edge router (English full name: ProviderEdge, English abbreviation: PE) at the sending end After being converted into Ethernet packets, they are encapsulated into MPLSVPN by the edge router at the receiving end to realize the transmission of leased line service packets in the network domain; English abbreviation: BGP) transfers labels between different network domains to realize the transmission of leased line service packets in the network domain. However, both technologies have the problems of complicated technology for interconnection between different network domains and heavy configuration workload of each IP bearer network. Moreover, the configuration will become more and more complicated with the increase of private line service packets.

Contents of the invention

Embodiments of the present invention provide a method and device for forwarding private line service messages, without adding or changing configurations of existing IP bearer networks, so as to realize the transmission of private line service messages in the network domain.

In order to achieve the above object, embodiments of the present invention adopt the following technical solutions:

In the first aspect, a method for forwarding private line service packets is provided, including:

After the first access gateway obtains the dedicated line service message, the first interface, and the destination Internet protocol IP address for forwarding the dedicated line service message, it determines the general routing encapsulation GRE tunnel according to the first interface, and the source of the GRE tunnel The IP address is the IP address of the first access gateway, and the destination IP address of the GRE tunnel is the IP address of the second access gateway;

The first access gateway acquires a pseudowire PW label; wherein, the PW labels of the private line service messages sent to the same access gateway are different, and the PW labels of the private line service messages sent to different access gateways may be the same;

The first access gateway performs MPLS encapsulation to obtain an MPLS-encapsulated leased line service message; the first access gateway performs GRE encapsulation on the MPLS-encapsulated leased line service message to obtain a GRE-encapsulated leased line service message;

The first access gateway sends the GRE-encapsulated leased line service packet to the second access gateway through the GRE tunnel.

The method for forwarding the leased line service message provided by the first aspect above first establishes a GRE tunnel between the two domains, then performs MPLS encapsulation and GRE encapsulation on the leased line service message to obtain the GRE encapsulated leased line service message, and passes through the GRE tunnel Transmit GRE-encapsulated private line service packets to the access gateway at the opposite end, so that there is no need to add or change the configuration of existing IP bearer networks, and realize the transmission of private line service packets in the network domain.

In a second aspect, a first access gateway is provided, including:

An acquisition unit, configured to acquire a leased line service message, a first interface, and a destination Internet Protocol IP address for forwarding the leased line service message, the first interface being the first access gateway for acquiring the leased line service message interface, the destination IP address is the address of the second access gateway that the private line service message needs to reach;

A processing unit, configured to determine a general routing encapsulation GRE tunnel according to the first interface, the source IP address of the GRE tunnel is the IP address of the first access gateway, and the destination IP address of the GRE tunnel is the first 2. The IP address of the access gateway;

The acquiring unit is further configured to acquire a pseudowire PW label, and the PW label is used to make the second access gateway forward the private line service message according to the PW label;

The processing unit is also used to perform multi-protocol label switching MPLS encapsulation to obtain an MPLS-encapsulated private line service message, and the MPLS-encapsulated private line service message header includes the PW label;

The processing unit is also used to perform GRE encapsulation on the MPLS-encapsulated private line service message to obtain a GRE-encapsulated private line service message, and the GRE-encapsulated private line service message header includes the source IP address of the GRE tunnel and the purpose of the GRE tunnel IP address;

A sending unit, configured to send the GRE-encapsulated leased line service message to the second access gateway through the GRE tunnel.

The first access gateway provided by the above-mentioned second aspect first establishes a GRE tunnel between the two domains, then performs MPLS encapsulation and GRE encapsulation on the private line service message, obtains the GRE encapsulated private line service message, and transmits the GRE tunnel to the opposite party through the GRE tunnel. The access gateway at the end transmits GRE-encapsulated leased line service packets, so that there is no need to add or change the configuration of existing IP bearer networks, and realize the transmission of leased line service packets in the network domain.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only These are some embodiments of the present invention. Those skilled in the art can also obtain other drawings based on these drawings without creative work.

FIG. 1 is a schematic diagram of a network for forwarding service packets provided by an embodiment of the present invention;

FIG. 2 is a flow chart of a method for forwarding private line service packets provided by an embodiment of the present invention;

FIG. 3 is a flow chart of another method for forwarding private line service packets provided by an embodiment of the present invention;

FIG. 4 is a schematic structural diagram of a first access gateway provided by an embodiment of the present invention;

FIG. 5 is a schematic structural diagram of another first access gateway provided by an embodiment of the present invention;

Fig. 6 is a schematic structural diagram of a second access gateway provided by an embodiment of the present invention.

detailed description

The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some, not all, embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

The basic principle of the present invention is: to establish a generic routing encapsulation (English full name: generic routing encapsulation, English abbreviation: GRE) tunnel between the first access gateway and the second access gateway based on the IP bearer network, that is, the first access gateway and the second access gateway A virtual circuit (VirtualCircuit, English abbreviation: VC) between the access gateways, the first access gateway performs MPLS and GRE encapsulation on the acquired leased line service packets, and passes through the first access gateway and the second access gateway The GRE tunnel sends the encapsulated leased line service message to the second access gateway.

The present invention provides a schematic diagram of a network for forwarding service messages. As shown in FIG. 1 , the local IP bearer network of city A includes an access gateway 1 . The local IP bearer network of city B includes an access gateway 2 . The local IP bearer network of city A and the local IP bearer network of city B transmit leased line service packets through their respective access gateways. At the same time, the IP bearer network also carries leased line service packets. The city's local IP bearer network transmits leased line service packets. It should be noted that the access gateway 1 pre-configures the IP address of the access gateway 2, so that the access gateway 1 transmits the private line service message to the access gateway 2. Similarly, the access gateway 2 pre-configures the IP address of the access gateway 1, so that the access gateway 2 transmits the leased line service message to the access gateway 1.

Embodiment one

An embodiment of the present invention provides a method for forwarding private line service packets, as shown in FIG. 2 , including:

Step 101, the first access gateway obtains the leased line service message, the first interface, and the destination IP address for forwarding the leased line service message.

For example, a user terminal in the local IP bearer network of city A sends a leased line service packet to a user equipment in the local IP bearer network of city B. First, the user terminal in the local IP bearer network of city A needs to send the leased line service The message is sent to access gateway 1. At this time, access gateway 1 is the first access gateway, and the first access gateway has obtained the leased line service message.

The first interface is an interface of the first access gateway that obtains the leased line service message. The destination IP address is the address of the second access gateway to which the private line service message needs to reach.

The first access gateway can access the first network domain, and the second access gateway can access the second network domain. The first network domain and the second network domain can be the same network domain or different network domains. .

Step 102, the first access gateway determines the GRE tunnel according to the first interface.

If the first access gateway has not established the GRE tunnel corresponding to the first interface, the first access gateway establishes a GRE tunnel between the first access gateway and the second access gateway, and the source IP address of the GRE tunnel is the The IP address of the first access gateway, and the destination IP address of the GRE tunnel is the IP address of the second access gateway. And the first access gateway stores the GRE tunnel corresponding to the first interface, so that after the first access gateway receives the leased line service packet from the first interface, it forwards the leased line service packet through the GRE tunnel.

If the first access gateway has established the GRE tunnel corresponding to the first interface, the first access gateway acquires the GRE tunnel corresponding to the first interface according to the first interface.

Tunneling is a method of transferring data between networks by using the infrastructure of the Internet. The data transferred using the tunnel can be data frames or packets of different protocols. The tunneling protocol repackages data frames or packets of other protocols and sends them through the tunnel. The new frame header provides routing information for passing encapsulated data across the Internet.

GRE is defined in RFC1701 and RFC1702, which specifies how to use one network layer protocol to encapsulate another network layer protocol.

Step 103, the first access gateway obtains the PW label.

Obtaining the pseudowire (English full name: prisonerofwar, English abbreviation: PW) label by the first access gateway may include statically obtaining the PW label and dynamically obtaining the PW label. The PW label is used to identify different leased line service packets. The PW labels of the leased line service packets sent to the same access gateway are different, and the PW labels of the leased line service packets sent to different access gateways may be the same.

The first access gateway may also send a request message to the second access gateway, the second access gateway receives the request message sent by the first access gateway, and the second access gateway obtains a The PW label sends a response message to the first access gateway, where the response message includes the PW label allocated for the first access gateway, that is, dynamically obtains the PW label.

Since the leased line service is usually a point-to-point service, if the first access gateway has sent the leased line service packet obtained from the first interface, the first access gateway stores the used PW label, After an interface obtains the private line service message, the first access gateway may use the used PW label stored by the first access gateway.

Step 104, the first access gateway performs MPLS encapsulation to obtain the MPLS-encapsulated leased line service message.

When the leased line service is an Ethernet service, the first access gateway can directly perform MPLS encapsulation on the obtained leased line service message to obtain an MPLS-encapsulated leased line service message. The header of the MPLS-encapsulated leased line service message includes the PW label and the leased line service message.

In particular, when the leased line service is Time Division Multiplexing (English full name: TimeDivisionMultiplexing, English abbreviation: TDM), asynchronous transfer mode (English full name: AsynchronousTransferMode, English abbreviation: ATM) or Ethernet service, the first access gateway needs to first Execute unified PWE3 encapsulation for private line service packets to obtain PWE3-encapsulated private line service packets, and then perform MPLS encapsulation on PWE3-encapsulated private line service packets to obtain MPLS-encapsulated private line service packets. The packet header of MPLS-encapsulated private line service packets includes PW labels and leased line service packets. The PW label is used to make the second access gateway forward the leased line service packet according to the PW label.

Edge-to-edge pseudowire emulation (English full name: Pseudo-WireEmulationEdgetoEdge, English abbreviation: PWE3) refers to imitating the asynchronous transmission mode (English full name: AsynchronousTransferMode, English abbreviation: ATM), frame relay, Ethernet, low-speed TDM circuits and other services of the basic behavior and characteristics of a two-layer service bearer technology.

Step 105: The first access gateway performs GRE encapsulation on the MPLS-encapsulated leased line service message to obtain the GRE-encapsulated leased line service message.

GRE-encapsulated leased line service packets include the source IP address of the GRE tunnel, the destination IP address of the GRE tunnel, and the MPLS-encapsulated leased line service packet. The source IP address of the GRE tunnel is the IP address of the first access gateway, and the destination IP address of the GRE tunnel is the IP address of the second access gateway.

The protocol type in the GRE tunnel header is identified as the PW label, that is, 0x8847.

Step 106, the first access gateway sends a GRE-encapsulated leased line service message to the second access gateway.

Further, as shown in FIG. 3 , the method for forwarding private line service packets provided by the embodiment of the present invention further includes steps 108 to 110 .

Step 107, the second access gateway receives the GRE-encapsulated leased line service message sent by the first access gateway.

The IP bearer network forwards the GRE-encapsulated leased line service packet to the second access gateway through the GRE tunnel between the first access gateway and the second access gateway according to the destination IP address of the GRE tunnel in the header of the GRE-encapsulated leased line service packet. Gateway, the second access gateway receives the GRE-encapsulated leased line service message sent by the first access gateway, that is, after receiving the GRE-encapsulated leased line service message, the second access gateway decapsulates the GRE-encapsulated leased line service message to obtain the GRE The destination IP address of the tunnel is the IP address of the second access gateway itself, and the MPLS-encapsulated leased line service packet, and step 108 is executed.

Step 108, the second access gateway decapsulates the MPLS-encapsulated leased line service message.

The second access gateway decapsulates the MPLS-encapsulated leased line service message to obtain the PW label and the leased line service message.

In particular, if the second access gateway decapsulates the MPLS-encapsulated private line service message to obtain the PWE3-encapsulated private line service message and the PW label, it also needs to decapsulate the PWE3-encapsulated private line service message to obtain the private line service message. The decapsulation method of leased line service packets corresponds to its encapsulation.

Step 109, the second access gateway forwards the leased line service message.

Query the forwarding table through the PW label. The forwarding table includes the corresponding relationship between the PW label and the outgoing interface, and use the queried outgoing interface to send the decapsulated private line service message.

For example, the first access gateway described in the embodiment of the present invention may be the access gateway 1 in the local IP bearer network of city A, and the second access gateway may be the access gateway in the local IP bearer network of city B 2. A GRE tunnel between the access gateway 1 in the local IP bearer network of city A and the access gateway 2 in the local IP bearer network of city B is established. Access gateway 1 in the local IP bearer network of city A performs MPLS encapsulation on the leased line service message, obtains the MPLS-encapsulated leased line service message, and then performs GRE encapsulation, obtains the GRE-encapsulated leased line service message, and then sends the private line service message to the local Access gateway 2 in the IP bearer network sends a GRE-encapsulated leased line service packet, and access gateway 2 in the local IP bearer network of city B receives the GRE-encapsulated leased line service packet, decapsulates the GRE-encapsulated leased line service packet, and confirms The second destination IP address is the IP address of the access gateway 2 itself, and the access gateway 2 decapsulates the MPLS-encapsulated leased line service message to obtain the PW label, and obtains the outbound interface of the access gateway 2 by querying the forwarding table according to the PW label. Decapsulated leased line service packets are sent to the outbound interface.

For leased line service packets that need to be transmitted between different network domains, first establish a GRE tunnel between the two network domains, then perform MPLS encapsulation and GRE encapsulation on the leased line service packets to obtain GRE-encapsulated leased line service packets, GRE-encapsulated leased line service packets are transmitted to the access gateway at the opposite end through the GRE tunnel, so that there is no need to add or change the configuration of existing IP bearer networks, and the transmission of leased line service packets in the network domain is realized.

Embodiment two

An embodiment of the present invention provides a first access gateway 20, as shown in FIG. 4 , including:

The acquiring unit 201 is configured to acquire a leased line service message, a first interface, and a destination Internet Protocol IP address for forwarding the leased line service message, the first interface being the first access port for acquiring the leased line service message The interface of the gateway, the destination IP address is the address of the second access gateway that the private line service message needs to reach;

The processing unit 202 is configured to determine a general routing encapsulation GRE tunnel according to the first interface, the source IP address of the GRE tunnel is the IP address of the first access gateway, and the destination IP address of the GRE tunnel is the The IP address of the second access gateway;

The acquiring unit 201 is further configured to acquire a pseudowire PW label, and the PW label is used to make the second access gateway forward the leased line service message according to the PW label;

The processing unit 202 is further configured to perform MPLS encapsulation to obtain an MPLS-encapsulated private line service message, and the MPLS-encapsulated private line service message header includes the PW label;

The processing unit 202 is further configured to perform GRE encapsulation on the MPLS-encapsulated private line service message to obtain a GRE-encapsulated private line service message, and the GRE-encapsulated private line service message header includes the source IP address of the GRE tunnel and the GRE tunnel address. Destination IP address;

A sending unit 203, configured to send the GRE-encapsulated leased line service message to the second access gateway through the GRE tunnel.

For leased line service packets that need to be transmitted between different network domains, first establish a GRE tunnel between the two domains, then perform MPLS encapsulation and GRE encapsulation on the leased line service packets to obtain GRE-encapsulated leased line service packets, and pass The GRE tunnel transmits GRE-encapsulated leased line service packets to the access gateway at the opposite end, so that there is no need to add or change the configuration of existing IP bearer networks, and realize the transmission of leased line service packets in the network domain.

The processing unit 202 is specifically configured to establish a GRE tunnel between the first access gateway and the second access gateway according to the first interface.

The acquiring unit 201 is specifically configured to acquire a PW label from a pre-stored PW label pool;

Alternatively, the sending unit 203 is further configured to send a request message to the second access gateway;

As shown in Figure 5, the first access gateway 20 also includes:

The receiving unit 204 is configured to receive a response message sent by the second access gateway, where the response message includes the assigned PW label.

When the private line service is time division multiplexing TDM service, asynchronous transfer mode ATM or Ethernet service,

The processing unit 202 is further configured to perform edge-to-edge PWE3 encapsulation on the private line service message to obtain a PWE3-encapsulated private line service message.

The processing unit 202 is specifically configured to perform MPLS encapsulation on the PWE3-encapsulated private line service message.

Embodiment three

An embodiment of the present invention provides a second access gateway 30, as shown in FIG. 6, including:

The receiving unit 301 is configured to receive the GRE-encapsulated leased line service message sent by the first access gateway;

The IP bearer network forwards the GRE-encapsulated leased line service packet to the second access gateway through the GRE tunnel between the first access gateway and the second access gateway according to the destination IP address of the GRE tunnel in the header of the GRE-encapsulated leased line service packet. Gateway, the second access gateway receives the GRE-encapsulated leased line service message sent by the first access gateway, that is, after receiving the GRE-encapsulated leased line service message, the second access gateway decapsulates the GRE-encapsulated leased line service message to obtain the GRE The destination IP address of the tunnel is the IP address of the second access gateway itself, and the MPLS-encapsulated private line service message.

The processing unit 302 is configured to decapsulate MPLS-encapsulated leased line service packets.

The second access gateway decapsulates the MPLS-encapsulated leased line service message to obtain the PW label and the leased line service message.

In particular, if the second access gateway decapsulates the MPLS-encapsulated private line service message to obtain the PWE3-encapsulated private line service message and the PW label, it also needs to decapsulate the PWE3-encapsulated private line service message to obtain the private line service message. The decapsulation method of leased line service packets corresponds to its encapsulation.

The sending unit 303 is configured to forward the leased line service message.

Query the forwarding table through the PW label. The forwarding table includes the corresponding relationship between the PW label and the outgoing interface, and use the queried outgoing interface to send the decapsulated private line service message.

Those skilled in the art can clearly understand that for the convenience and brevity of description, the specific working process of the above-described devices and units can refer to the corresponding process in the foregoing method embodiments, and details are not repeated here.

Those of ordinary skill in the art can understand that all or part of the steps for realizing the above-mentioned method embodiments can be completed by hardware related to program instructions, and the aforementioned program can be stored in a computer-readable storage medium. When the program is executed, the It includes the steps of the above method embodiments; and the aforementioned storage medium includes: ROM, RAM, magnetic disk or optical disk and other various media that can store program codes.

The above is only a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Anyone skilled in the art can easily think of changes or substitutions within the technical scope disclosed in the present invention. Should be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention should be determined by the protection scope of the claims.

Claims (10)

1. A method for forwarding private line service messages, characterized in that, comprising: The first access gateway obtains the leased line service message, the first interface and the destination Internet protocol IP address for forwarding the leased line service message, and the first interface is the first access gateway that obtains the leased line service message interface, the destination IP address is the address of the second access gateway that the private line service message needs to reach; The first access gateway determines a general routing encapsulation GRE tunnel according to the first interface, the source IP address of the GRE tunnel is the IP address of the first access gateway, and the destination IP address of the GRE tunnel is the The IP address of the second access gateway; The first access gateway acquires a pseudowire PW label, and the PW label is used to enable the second access gateway to forward the leased line service message according to the PW label; The first access gateway performs multi-protocol label switching MPLS encapsulation to obtain an MPLS-encapsulated private line service message, and the MPLS-encapsulated private line service message header includes the PW label; The first access gateway performs GRE encapsulation on the MPLS-encapsulated private line service message to obtain a GRE-encapsulated private line service message, and the GRE-encapsulated private line service message header includes the source IP address of the GRE tunnel and the destination IP address of the GRE tunnel address; The first access gateway sends the GRE-encapsulated leased line service packet to the second access gateway through the GRE tunnel. 2. The method according to claim 1, wherein said first access gateway determines a general routing encapsulation GRE tunnel according to said first interface comprising: The first access gateway establishes a GRE tunnel between the first access gateway and the second access gateway according to the first interface. 3. The method according to claim 1, wherein the acquiring the pseudowire PW label by the first access gateway comprises: The first access gateway acquires a PW label from a pre-stored PW label pool; Or, the first access gateway sends a request message to the second access gateway; The first access gateway receives the response message sent by the second access gateway, where the response message includes the allocated PW label. 4. The method according to claim 1, characterized in that, when the private line service is time division multiplexing TDM service, asynchronous transfer mode ATM or Ethernet service, before the first access gateway performs MPLS encapsulation, the method Also includes: The first access gateway performs edge-to-edge PWE3 encapsulation on the private line service message to obtain a PWE3-encapsulated private line service message. 5. The method according to claim 4, wherein said first access gateway performing MPLS encapsulation comprises: The first access gateway performs MPLS encapsulation on the PWE3-encapsulated private line service message. 6. A first access gateway, characterized in that, comprising: An acquisition unit, configured to acquire a leased line service message, a first interface, and a destination Internet Protocol IP address for forwarding the leased line service message, the first interface being the first access gateway for acquiring the leased line service message interface, the destination IP address is the address of the second access gateway that the private line service message needs to reach; A processing unit, configured to determine a general routing encapsulation GRE tunnel according to the first interface, the source IP address of the GRE tunnel is the IP address of the first access gateway, and the destination IP address of the GRE tunnel is the first 2. The IP address of the access gateway; The acquiring unit is further configured to acquire a pseudowire PW label, and the PW label is used to enable the second access gateway to forward the leased line service message according to the PW label; The processing unit is also used to perform multi-protocol label switching MPLS encapsulation to obtain an MPLS-encapsulated private line service message, and the MPLS-encapsulated private line service message header includes the PW label; The processing unit is also configured to perform GRE encapsulation on the MPLS-encapsulated private line service message to obtain a GRE-encapsulated private line service message, and the GRE-encapsulated private line service message header includes the source IP address of the GRE tunnel and the purpose of the GRE tunnel IP address; A sending unit, configured to send the GRE-encapsulated leased line service message to the second access gateway through the GRE tunnel. 7. The first access gateway according to claim 6, characterized in that, The processing unit is specifically configured to establish a GRE tunnel between the first access gateway and the second access gateway according to the first interface. 8. The first access gateway according to claim 6, characterized in that, The acquiring unit is specifically configured to acquire a PW label from a pre-stored PW label pool; Or, the sending unit is further configured to send a request message to the second access gateway; The first access gateway also includes: A receiving unit, configured to receive a response message sent by the second access gateway, where the response message includes the assigned PW label. 9. The first access gateway according to claim 6, wherein when the dedicated line service is time division multiplexing TDM service, asynchronous transfer mode ATM or Ethernet service, The processing unit is further configured to perform edge-to-edge PWE3 encapsulation on the private line service message to obtain a PWE3 encapsulated private line service message. 10. The first access gateway according to claim 9, characterized in that, The processing unit is specifically configured to perform MPLS encapsulation on the PWE3-encapsulated leased line service message.