WO2012088909A1

WO2012088909A1 - Method and device for updating vpn routing

Info

Publication number: WO2012088909A1
Application number: PCT/CN2011/078974
Authority: WO
Inventors: 张栋; 王海波
Original assignee: 华为技术有限公司
Priority date: 2010-12-31
Filing date: 2011-08-26
Publication date: 2012-07-05
Also published as: CN102158393B; CN102158393A

Abstract

Embodiments of the present invention relates to a method and device for updating VPN routing. A method for updating VPN routing comprises: a provider edge PE device determining a management state of a virtual private network VPN; the PE device informing a peer PE device of the management state of the VPN, so that the peer PE device updates, according to the management state of the VPN, routing information of the VPN. The routing processing on the VPN is implemented through informing of the management state of the VPN, so that it is not required to perform one-by-one updating on the VPN routing, thereby implementing a series of expanded functions such as VPN routing rapid updating and revoking, and solving the problems of a large amount of message processing and service convergence.

Description

The present invention claims the priority of the Chinese patent application filed on Dec. 31, 2010, the Chinese Patent Application No. 201010624349.4, entitled "A VPN Routing Update Method and Apparatus". The entire contents are incorporated herein by reference. The present invention relates to the field of communications technologies, and in particular, to a VPN routing update method and apparatus. Background technique

A VPN (Virtual Private Network) establishes a temporary, secure connection through a public network (usually the Internet Internet).

BGP (Border Gateway Protocol) / MPLS (Multiprotocol)

Label Switching (Multi-Protocol Label Switching) IP (Internet Protocol) VPN is a Layer 3 Virtual Private Network (L3VPN) that uses BGP on the SP (Service Provider) backbone network. Publish VPN routes and use MPLS to forward VPN packets on the service provider backbone network. The IP here refers to the IP packet carried by the VPN.

The basic model of BGP/MPLS IP VPN consists of three parts:

CE (Customer Edge) device: An interface is directly connected to the service provider network. The CE can be a router or a switch, or it can be a host.

PE (Provider Edge) device: Directly connected to the CE. In an MPLS network, all processing of the VPN occurs on the PE.

P (Provider, Provider Backbone) device: Not directly connected to the CE. The P device only needs to have basic MPLS forwarding capability and does not maintain VPN information. In order to properly handle VPN routing, use RFC2858 (Multiprotocol Extensions for

MP-BGP (Multi-Protocol Extension - Border Gateway Protocol) as defined in BGP-4, Multiprotocol Extension for BGP-4. MP-BGP implements support for multiple network layer protocols. In the Update message, the network layer will be negotiated, I; reflect ^jNLRI (Network Layer Reachability Information) and Next Hop (under One jump).

Specifically, when the following scenario occurs: The user shuts down the entire VPN; or the status of the VPN-related interface changes from up (active) to down (inactive); or when the VPN-related protocol status changes from up to down, the PE device All the routes of the VPN are encapsulated into the revoked packets and sent to the peer PE device. After receiving the revoked packets, the peer PEs parse them one by one, and then perform the revocation process, which triggers the re-routing calculation. For example, a PE device can carry MP_UNREACH_NLRI

(Multiprotocol Unreachable NLRI, Multi-Protocol Unreachable NLRI) Update message of the attribute to revoke the VPN route one by one.

The following scenarios occur: User undo shutdown (recovery) The entire VPN: The PE device needs to update the VPN routes one by one to notify the peer PE device of the rerouting calculation.

With the above-mentioned prior art, the VPN routes need to be updated one by one. When the amount of VPN routes is particularly large, the VPN routing update needs to process a large number of packets, resulting in a longer service convergence time. SUMMARY OF THE INVENTION Embodiments of the present invention provide a method and apparatus for updating a VPN route, which implements fast update of a VPN route.

In one aspect, an embodiment of the present invention provides a method for updating a VPN route, including:

Provider edge PE device determines the management status of the virtual private network VPN;

The PE device notifies the peer PE device of the management status of the VPN, so that the peer PE device updates the routing information of the VPN according to the VPN management status. On the other hand, an embodiment of the present invention provides a VPN routing update apparatus, including: a determining unit, configured to determine a management state of a virtual private network VPN;

The notification unit is configured to notify the peer PE device of the management status of the VPN, so that the peer PE device updates the routing information of the VPN according to the VPN management status.

According to the technical solution provided by the foregoing embodiment of the present invention, the routing process of the VPN is implemented by notifying the management state of the VPN, and the VPN route is not required to be updated one by one, thereby enabling rapid update and revocation of the VPN route. A series of extended functions that solve a large number of message processing and service convergence problems. BRIEF DESCRIPTION OF THE DRAWINGS In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments will be briefly described below. It is obvious that the drawings in the following description are only some implementations of the present invention. For example, other drawings may be obtained from those skilled in the art without any inventive labor.

1 is a schematic flowchart of a method for updating a VPN route according to an embodiment of the present invention;

2 is a schematic diagram 1 of a VPN routing update apparatus according to an embodiment of the present invention;

FIG. 3 is a schematic diagram 2 of a VPN routing update apparatus according to an embodiment of the present invention.

The technical solutions in the embodiments of the present invention are clearly and completely described in the following with reference to the accompanying drawings in the embodiments of the present invention. It is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. example. All other embodiments obtained by a person of ordinary skill in the art based on the embodiments of the present invention without the creative work are all within the scope of the present invention.

As shown in FIG. 1 , an embodiment of the present invention provides a method for updating a VPN route, including:

11. The PE device determines the management state of the VPN. 12. The PE device notifies the peer PE device of the management status of the VPN, so that the peer PE device updates the routing information of the VP N according to the VPN management status. Among them, one PE device can access multiple CE devices. A CE device can also connect multiple PE devices belonging to the same or different service providers.

For example, the PE device in the above 11 determines the management state of the VPN, and may include one or more of the following situations:

The PE device monitors whether the VPN interface or routing protocol is inactive. When the VPN interface or routing protocol is inactive, the management status of the VPN is Down.

Alternatively, the PE device monitors whether the user shuts down the VPN. When the user shuts down the VPN, it determines that the management state of the VPN is Stale (temporary inactive).

Or, the PE device monitors whether the user undo shutdown VPN, when the user undo shutdown

In the VPN, the management status of the VPN is determined to be Active.

For example, the management status of the VPN can include:

Down state: The VPN-related interface or routing protocol is inactive.

Stale state: Under the shutdown operation, the VPN is temporarily inactive.

Active state: VPN-related interfaces and routing protocols are active.

For example, the PE device in the above 12 notifies the peer PE device of the VPN management status, which may include:

The PE device notifies the peer PE device of the VPN management status through the VPN routing update packet.

The VPN routing update message may include a tlv (type-length-value) field. Among them, "type" can include the management status of the VPN.

"Length" can include the number of RD (Route Distinguisher). The "value" may include the RD value corresponding to the VPN. Exemplarily, the VPN routing update message may be an Update message. The embodiment of the invention extends a new MP-BGP route attribute: vpn status attribute

Type: optional non-transitive (optional non-transition);

Consists of a series of type-length-value (tlv):

Type: VPN-ToDown

VPN-ToStale

VPN -To Active

Length: the number of RD

Value: RD value corresponding to the VPN

For example, multiple VPNs can be configured based on one PE, and different VPNs correspond to different RD values.

For example, the method for updating a VPN route in the embodiment of the present invention may further include:

The PE device sets the mapping between the management status of the VPN, the VPN routing update packet, and the VPN routing information processing mode.

For example, the management status of the VPN is Down. The VPN routing information processing mode is that the peer PE device deletes the routing information of the VPN. At this point, the routing information of the VPN is no longer involved in the route calculation.

Or, the management status of the VPN is in the Stale state. The VPN routing information processing mode is that the peer PE device does not delete the routing information of the VPN, and keeps the routing information of the VPN in the Stale state. At this point, the routing information of the VPN is no longer involved in the route calculation.

Or, the management status of the VPN is the active state. The VPN routing information processing mode is that the peer PE device recovers the routing information of the VPN in the Stale state. At this point, the VPN routing information is restored and then participates in route calculation.

It can be seen from the technical solution provided by the foregoing embodiments of the present invention that the routing processing of the VPN is implemented by notifying the management state of the VPN, and the VPN routing is no longer required to be updated one by one. A series of extended functions, such as rapid update and revocation of VPN routes, solve a large number of packet processing and service convergence problems.

The PE device negotiates with the peer PE device to set the mapping between the management status of the VPN, the VPN routing update packet, and the V P N routing information processing mode.

For example, negotiation is performed when establishing a BGP session, and VPN status notification and learning capabilities are supported. If at least one of the two peer PEs does not support the vpn status attribute, the Update packet does not contain the attributes. Then, the peer PE performs routing processing according to the BGP protocol of the prior art.

In this way, after receiving the VPN routing update packet, the peer PE device can determine the corresponding VPN management state, and then update the VPN routing information by using the corresponding VPN routing information processing mode.

It can be seen that the VPN routing update method in the embodiment of the present invention performs the capability negotiation during the establishment of the BGP session, continues to maintain the original capability, and directly adds the new capability, so that the solution of the present invention can be incrementally deployed in the network.

As shown in FIG. 2, corresponding to the VPN routing update method in the foregoing embodiment, the embodiment of the present invention provides a VPN routing update apparatus, including:

The determining unit 21 is configured to determine a management state of the VPN.

The notification unit 22 is configured to notify the peer PE device of the management status of the VPN, so that the peer PE device updates the routing information of the VPN according to the management status of the VPN.

For example, the VPN route update device in the embodiment of the present invention may be a PE device.

For example, as shown in FIG. 3, the above determining unit 21 may include one or more of the following units:

The first determining unit 21 1 is configured to monitor whether the interface or the routing protocol of the VPN is in an inactive state. When the interface or the routing protocol of the VPN is in an inactive state, determine that the management state of the VPN is an inactive Down state. Alternatively, the second determining unit 212 is configured to monitor whether the user shuts down the VPN, and when the user shuts down the VPN, determine that the management state of the VPN is a temporary inactive Stale state.

Alternatively, the third determining unit 213 is configured to monitor whether the user undos the shutdown VPN, and when the user undos the shutdown VPN, determines that the management state of the VPN is an active Active state.

For example, the management status of the VPN can include:

Down state: The VPN-related interface or routing protocol is inactive.

Stale state: Under the shutdown operation, the VPN is temporarily inactive.

Active state: VPN-related interfaces and routing protocols are active.

For example, the notification unit 22 may be specifically configured to notify the peer PE device of the management status of the VPN by using the VPN routing update message.

The VPN routing update message may include a tlv (type-length-value) field. Among them, "type" can include VPN management status.

"Length" can include the number of RD (Route Distinguisher). The "value" may include the RD value corresponding to the VPN.

For example, as shown in FIG. 3, the VPN routing update apparatus of the embodiment of the present invention may further include: a setting unit 31, configured to set a correspondence between a VPN management state, a VPN routing update packet, and a VPN routing information processing manner. relationship.

The negotiation unit 32 is configured to negotiate with the peer PE device to set a correspondence between the management state of the VPN, the VPN routing update packet, and the VPN routing information processing mode.

Or, the management status of the VPN is in the stale state, and the VPN routing information processing mode is the peer. The PE device does not delete the routing information of the VPN, and keeps the routing information of the VPN in the Stale state. At this point, the routing information of the VPN is no longer involved in the route calculation.

It can be seen from the technical solution provided by the foregoing embodiments of the present invention that the routing processing of the VPN is implemented by notifying the management state of the VPN, and the VPN routing is no longer updated one by one, thereby enabling rapid update and revocation of the VPN route. The extended function of the series solves a large number of message processing and service convergence problems.

By performing capability negotiation when establishing a BGP session, the original capability is maintained, and new capabilities are directly added, so that the solution of the present invention can be incrementally deployed in the network.

For example, the following describes the VPN routing update method in the embodiment of the present invention: The user shutdowns the entire VPN scenario: In the network application, the user often deploys a redundant device (such as a PE device) for service protection. When the network is connected to the link, the user needs to migrate the service from the primary device to the backup device. To achieve fast processing, you usually need to shut down the entire VPN.

The status of the VPN-related interface changes from up to down. A VPN can be associated with multiple outbound interfaces. However, the most common one is to associate an outbound interface. When the status of the outbound interface changes from up to down, the entire VPN service cannot be used. Continue to work normally, you need to revoke all VPN routes.

The status of the VPN-related protocol changes from up to down. In the VPN network, dynamic routing protocols are often deployed between PEs and CEs, such as the ISIS (Intermediate System to Intermediate System) protocol and OSPF (Open Shortest Path First). Open Shortest Path First) protocol or BGP protocol for route learning and publishing. When the VPN-related routing protocol changes from up to down, it means that the entire VPN service cannot continue normally. All VPNs need to be revoked. routing.

The user undo shutdown of the entire VPN scenario: This means that the entire VPN service is restored. The routes need to be updated one by one to notify the peer PE device to re-calculate the route.

For example, the embodiment of the present invention extends a new MP-BGP route attribute: vpn status attribute

Type: optional non-transitive;

Consists of a series of type-length-value (tlv):

Type: VPN-ToDown

VPN-ToStale

VPN-ToActive

Length: the number of RD

Value: RD value corresponding to the VPN

The route update message and route processing method for notifying three VPN states:

VPN-ToDown: After the peer PE device receives it, it completely deletes the VPN route.

VPN-ToStale: After the peer PE device receives the VPN route, it keeps the VPN route in the Stale state.

VPN-ToActive: The peer PE device recovers the VPN route in the Stale state after receiving it. When the user shuts down the entire VPN scenario, the PE device sends the VP N-To Stale packet to notify the peer PE device that the VPN of the PE device is temporarily in the Stale state. After the peer PE device receives the packet, the PE device receives the packet. The VPN route received from this PE device is placed in the stale state and is not deleted, but is no longer involved in route calculation.

When the status of the VPN-related interface changes from up to down, or the status of the VPN-related protocol changes from up to down, the PE sends a VPN-ToDown packet to notify the peer PE that the VPN of the PE is present. In the Down state, after receiving the packet, the peer PE device deletes all the VPN routes received from the PE device and does not participate in route calculation. When the user undo shutdowns the entire VPN, the device sends a VPN-ToActive packet to notify the peer PE device that the VPN of the PE device is restored to the active state. After receiving the packet, the peer PE device receives the packet from the PE device. The VPN route recovery in the stale state participates in route calculation and achieves fast convergence.

In the embodiment of the present invention, the BGP protocol is extended to notify the management state of the VPN, so that the routing processing of the VPN is more flexible, thereby implementing a series of extended functions such as rapid update and revocation of the VPN route, and solving a large number of VPNs existing in the original BGP protocol. Routing interaction and slow convergence of VPN services.

It should be noted that, for the foregoing method embodiments, for the sake of simple description, they are all expressed as a series of action combinations, but those skilled in the art should understand that the present invention is not limited by the described action sequence. Because certain steps may be performed in other sequences or concurrently in accordance with the present invention. In addition, those skilled in the art should also understand that the embodiments described in the specification are all preferred embodiments, and the actions and modules involved are not necessarily required by the present invention.

In the above embodiments, the descriptions of the various embodiments are different, and the details are not described in the specific embodiments. For details, refer to related descriptions of other embodiments.

A person skilled in the art can understand that all or part of the process of implementing the above embodiment method can be completed by a computer program to instruct related hardware, and the program can be stored in a computer readable storage medium, the program When executed, the flow of an embodiment of the methods as described above may be included. The storage medium may be a magnetic disk, an optical disk, a read-only memory (ROM), or a random access memory (RAM). The above is only a preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can easily think of changes or within the technical scope disclosed by the present invention. Alternatives are intended to be covered by the scope of the present invention. Therefore, the scope of the invention should be determined by the scope of the claims.

Claims

Rights request

A VPN routing update method, comprising:

The PE device notifies the peer PE device of the management status of the VPN, so that the peer device can update the routing information of the VPN according to the management state of the VPN.

The VPN routing update method according to claim 1, wherein the PE device notifies the peer PE device of the management status of the VPN, including:

PE equipment;

The VPN routing update message includes a type-length-value tlv field, where the type includes a management state of the VPN; the length includes a number of routing specifiers RD; and the value includes an RD value corresponding to the VPN. .

The VPN routing update method according to claim 1 or 2, wherein the PE device determines the management state of the VPN, including:

Whether the PE device monitors whether the interface or routing protocol of the VPN is in an inactive state, when

When the interface or the routing protocol of the VPN is in an inactive state, determine that the management state of the VPN is an inactive Down state.

Alternatively, the PE device monitors whether the user shuts down the shutdown VPN, and when the user shuts down the VPN, determines that the management state of the VPN is a temporary inactive Stale state;

Alternatively, the PE device monitors whether the user restores the undo shutdown VPN. When the user undos the shutdown VPN, the management state of the VPN is determined to be an active Active state.

The method for updating a VPN route according to claim 3, wherein the method further comprises:

The PE device sets a VPN management state, a VPN routing update packet, and a VPN routing information. Correspondence between rational methods;

The management status of the VPN is an inactive Down state, and the VPN routing information processing mode is that the peer PE device deletes the routing information of the VPN;

Or, the management state of the VPN is a temporary inactive Stale state, and the VPN routing information processing manner is that the peer PE device does not delete the routing information of the VPN, and the routing information of the VPN is kept in the Stale state;

Alternatively, the management status of the VPN is an active Active state, and the VPN routing information processing mode is that the peer PE device restores the routing information of the VPN in the Stale state to the Active state.

The method for updating a VPN route according to claim 1 or 2, wherein the method further comprises:

The PE device negotiates with the peer PE device to set a correspondence between the management state of the VPN, the VPN routing update packet, and the VPN routing information processing mode.

A VPN routing update device, comprising:

a determining unit, configured to determine a management state of the virtual private network VPN;

The notification unit is configured to notify the peer PE device of the management status of the VPN, so that the peer PE device updates the routing information of the VPN according to the management status of the VPN.

The VPN routing update apparatus according to claim 6, wherein the notification PE device, the VPN routing update message includes a type-length-value tlv field, wherein the type includes the VPN The management state; the length includes the number of RD route specifiers; the value includes the RD value corresponding to the VPN.

The VPN routing update apparatus according to claim 6 or 7, wherein the determining unit comprises: a first determining unit, configured to monitor whether the interface or the routing protocol of the VPN is in an inactive state, and determine that the management state of the VPN is an inactive Down state when the interface or the routing protocol of the VPN is in an inactive state;

Or the second determining unit is configured to monitor whether the user closes the shutdown VPN, and when the user shuts down the VPN, determining that the management state of the VPN is a temporary inactive Stale state;

Alternatively, the third determining unit is configured to monitor whether the user restores the undo shutdown VPN. When the user undos the shutdown VPN, the management state of the VPN is determined to be an active Active state.

The device of the VPN routing device according to claim 8, wherein the device further comprises:

a setting unit, configured to set a correspondence between the management state of the VPN, the VPN routing update packet, and the VPN routing information processing manner;

Or, the management status of the VPN is a temporary inactive Stale state, and the VPN routing information processing manner is that the peer PE device does not delete the routing information of the VPN, and the routing information of the VPN is kept in the Stale state;

The device of the VPN routing device according to claim 6 or 7, wherein the device further comprises:

The negotiation unit is configured to negotiate with the peer PE device to set a correspondence between the management state of the VPN, the VPN routing update packet, and the VPN routing information processing mode.