WO2015184876A1

WO2015184876A1 - Vpn route label allocation method, asbr, pe and allocation system

Info

Publication number: WO2015184876A1
Application number: PCT/CN2015/073970
Authority: WO
Inventors: 刘准; 宋兵; 付琰; 韩杰
Original assignee: 中兴通讯股份有限公司
Priority date: 2014-10-30
Filing date: 2015-03-11
Publication date: 2015-12-10
Also published as: CN105634950B; CN105634950A

Abstract

A VPN router label allocation method, an ASBR, a PE and an allocation system. The method comprises: receiving a VPN route update message; judging whether to allocate a label to a new VPN router according to the VPN route update message; and if so, allocating a label to the new VPN router. In the technical solution, after a VPN route update message is received, whether a label needs to be allocated to a new VPN router first is judged at first, and the label is allocated merely when required. Compared with the related art where a label is allocated to a new VPN route immediately after a VPN route update message is received, the number of labels of a VPN router can be reduced, thereby relieving the pressure of an ASBR.

Description

VPN routing label allocation method, ASBR, PE and distribution system

Technical field

The present invention relates to the field of network communications, and in particular, to a virtual private network VPN routing label allocation method, an ASBR, a PE, and a distribution system.

Background technique

A private private network built using the public network is called a virtual private network (VPN). Sites belonging to one VPN may be connected to different gateways to set up PEs. To ensure VPN connectivity, we must be in PE. Exchange VPN routing information between. In a networking application, multiple sites of a user VPN may be connected to different AS (Application Server) domains of multiple ISPs (Internet Service Providers). This application mode is called cross-domain. VPN.

The cross-domain VPN needs to solve the problem that the LSP (Label Switched Path) cannot be cross-domain. The key is the configuration of the Autonomous System Boundy Router (ASBR). In the commonly used MP-EBGP (EBGP Redistribution of labeled VPN) In the networking mode of the IPv4 route, the ASBRs of each pair are required to exchange the label VPNv4 routes that they receive from the PEs in the own domain through the MP-EBGP, and establish an internal relationship between the ASBR and the PE (Provider Edge, the public network edge device) in the same domain. An external border gateway protocol EBGP neighbor is set up between the inter-AS and the ASBR. The ASBR needs to use its own address as the next hop when advertised routes to the PEs in the same domain. The ASBRs cannot enter the received VPNv4 routes. / Output destination Import/Export Targe filtering. The ASBRs advertise the label VPNv4 routes to the other party in the MP-EBGP mode. In the cross-domain VPN traffic, the labeled VPNv4 traffic is transmitted between the ASBRs. The networking model, route label advertisement, and traffic forwarding process are shown in Figure 1.

On the MP-EBGP network, all the private network routes of the local and other domains must be maintained on the ASBR. The ASBR needs to assign a label to each VPNv4 route. The ASBR pressure is high, and the number of VPN users accesses. The number of labels on the ASBR is also easily exceeded. The forwarding entries consume a large amount of memory. Adding or deleting VPNv4 routes needs to be broadcast to each forwarding board, which increases the burden on the ASBR system.

Therefore, how to provide a method for reducing VPN routing labels is a technical problem to be solved in the field.

Summary of the invention

The embodiment of the invention provides a VPN route label distribution method, an ASBR, a PE, and a distribution system, to solve the technical problem of how to reduce the VPN route label.

To solve the above technical problem, an embodiment of the present invention provides a virtual private network route label allocation method applied to an autonomous system border router ASBR, the method comprising: receiving a VPN route update message; determining whether it is new according to a VPN route update message. The VPN route allocates a label; according to the judgment result, assigns a new label to the new VPN route, or determines a label of the new VPN route.

Optionally, the step of determining, according to the VPN routing update message, whether to assign a label to the new VPN route includes: detecting whether the VPN routing update message carries the public network edge device PE identifier, and the public network edge device PE identifier is the source of the new VPN route. The identity of the PE of the network edge device; if the PE identifier of the public network edge device is not carried, the label is assigned to the new VPN route.

Optionally, the method further includes: if the PE identifier of the public network edge device is carried, the PE identifier of the public network edge device and the route identifier RD of the new VPN route are extracted, and the presence of the PE identifier and the new VPN route of the public network edge device are detected. The route identifier RD matches the label at the same time. If it does not exist, it assigns a label to the new VPN route. If it exists, the detected label is used as the label of the new VPN route.

Optionally, the identity identifier includes a link establishment address of the source public network edge device PE.

Optionally, the label is an ingress label of a new VPN route.

To solve the above technical problem, the embodiment of the present invention provides a method for allocating a virtual private network route label to a public network edge device PE. The method includes: when detecting a new VPN route in the virtual private network VPN, Detects the label allocation configuration; generates and sends a VPN routing update message according to the label allocation configuration.

Optionally, the label allocation configuration includes: configuring each label of each VPN routing forwarding table VRF; and the step of generating a VPN routing update message according to the label allocation configuration includes: The identity of the PE of the source public network edge device of the new VPN route is obtained, and is added to the VPN route update message as the public network edge device PE identifier.

To solve the above technical problem, the embodiment of the present invention provides a method for allocating a virtual private network route label, and the method includes: when the public network edge device PE detects that a new VPN route is added to the virtual private network VPN, detecting the label allocation configuration. According to the label allocation configuration, a VPN routing update message is generated and sent; the autonomous system border router ASBR receives and according to the VPN routing update message, determines whether to assign a label to the new VPN route, and if necessary, assigns a label to the new VPN route.

To solve the above technical problem, an embodiment of the present invention provides an autonomous system border router (ASBR), where the ASBR includes: a receiving module, configured to receive a VPN routing update message; and a determining module, configured to determine, according to the VPN routing update message, whether the new VPN is a new VPN a route distribution label; and an allocation module configured to allocate a label for the new VPN route when the judgment result of the determination module is required.

To solve the above technical problem, the embodiment of the present invention provides a public network edge device PE, where the PE includes: an inspection module, configured to detect a label allocation configuration when a new VPN route is detected in the virtual private network VPN; The sending module is configured to generate and send a VPN routing update message according to the label allocation configuration.

To solve the above technical problem, an embodiment of the present invention provides a virtual private network VPN route label distribution system, which includes an ASBR and a PE provided by an embodiment of the present invention.

In order to solve the above technical problem, an embodiment of the present invention provides a computer storage medium, where the computer storage medium stores computer executable instructions, and the computer executable instructions are used to execute the foregoing method.

Advantageous effects of embodiments of the present invention:

The solution provided by the embodiment of the present invention, after receiving the VPN routing update message, first determines whether a label needs to be allocated for the new VPN route, and only allocates the label when needed, and the related technology is after receiving the VPN routing update message. Compared with the new VPN route distribution label, the number of labels of the VPN route can be reduced, and the pressure of the ASBR is alleviated.

BRIEF abstract

1 is a schematic diagram of a VPN network and a routing label in the related art;

2 is a flowchart of a method for allocating a VPN route label according to the first embodiment of the present invention;

3 is a flowchart of a method for allocating a VPN route label according to a second embodiment of the present invention;

4 is a schematic diagram of a VPN network and a routing label in a second embodiment of the present invention.

Preferred embodiment of the invention

Further explanation of the embodiments of the present invention will be made in conjunction with the accompanying drawings.

First embodiment:

FIG. 2 is a flowchart of a method for allocating a VPN route label according to the first embodiment of the present invention. As shown in FIG. 2, the embodiment of the method for allocating a VPN route label according to the embodiment of the present invention includes the following steps:

S201: Receive a VPN route update message.

S202: Determine, according to the VPN routing update message, whether to allocate a label for the new VPN route.

Optionally, the step S202 includes: detecting whether the VPN routing update message carries the public network edge device PE identifier, and the public network edge device PE identifier is the identity identifier of the source public network edge device PE of the new VPN route; if not, the new The VPN route is assigned a label. If it is carried, the PE identifier of the public network edge device and the route identifier RD of the new VPN route are extracted, and the label matching the PE identifier of the public network edge device and the route identifier RD of the new VPN route is detected. If it does not exist, it assigns a label to the new VPN route. If it exists, it will use the detected label as the label of the new VPN route.

Optionally, the identity identifier in the foregoing embodiment includes a link establishment address of the source public network edge device PE; of course, it may also be a unique code of the source public network edge device PE (source PE), and the like may be determined. Source PE parameters;

Alternatively, step S202 includes: detecting whether the VPN routing update message carries a special flag (such as a field, etc.), or the content of the special flag, such as carrying a special field (or the content of the special flag is not required), indicating that the VPN routing update The VPN route corresponding to the message already has a label, and no longer assigns a label to it. If no special field is carried (or the content of the special flag is needed), the label is assigned to it;

S203: According to the judgment result, assign a new label to the new VPN route, or determine a label of the new VPN route.

Optionally, the label in the method shown in Figure 2 is an ingress label of the new VPN route.

The method shown in FIG. 2 is an embodiment of the VPN routing label allocation method provided by the embodiment of the present invention on the ASBR. Then, the embodiment of the VPN routing label allocation method provided by the embodiment of the present invention on the PE includes:

When it is detected that a new VPN route is added to the virtual private network VPN, the label allocation configuration is detected;

A VPN routing update message is generated and sent according to the label allocation configuration.

Optionally, the label allocation configuration in the foregoing embodiment includes: configuring each label of each VPN routing forwarding table VRF; generating a VPN routing update when the label allocation is configured to configure each label of each VPN routing forwarding table VRF The step of the message includes: obtaining the identity of the source public network edge device PE of the new VPN route, and adding it as the public network edge device PE identifier to the VPN route update message.

Correspondingly, the method for allocating the virtual private network route label in the embodiment of the present invention includes: when the initiator detects that a new VPN route is added to the virtual private network VPN, the detection label allocation configuration is configured according to the label. Configure, generate and send a VPN routing update message; the processing end receives and according to the VPN routing update message, determines whether to assign a label to the new VPN route, and if necessary, assigns a label to the new VPN route.

In order to implement the virtual private network route label allocation method provided by the embodiment of the present invention, the ASBR and the PE are improved in the embodiment of the present invention, and the improvement is as follows:

The ASBR provided by the embodiment of the present invention includes:

a receiving module, configured to receive a VPN routing update message;

The determining module is configured to determine, according to the VPN routing update message, whether to assign a label to the new VPN route;

The allocation module is configured to allocate a label for the new VPN route when the judgment result of the determining module is required.

The PE provided by the embodiment of the present invention includes:

The checking module is configured to detect a label allocation configuration when a new VPN route is added to the virtual private network VPN;

The sending module is configured to generate and send a VPN routing update message according to the label allocation configuration.

The virtual private network VPN route label distribution system provided by the embodiment of the present invention includes the ASBR and the PE provided by the embodiment of the present invention.

Second embodiment:

The embodiment of the present invention is further explained by using an application example in conjunction with FIG. 3 and FIG. 4. FIG. 3 is a flowchart of a method for allocating a VPN routing label according to a second embodiment of the present invention, and FIG. 4 is a second embodiment of the present invention. A schematic diagram of a VPN network and a routing label is used in the embodiment of the present invention. The VPN routing label allocation system in the embodiment of the present invention mainly includes a PE and an ASBR. In this embodiment, a hypothesis is assumed. The VPN2 network already includes the route A, and the ASBR1, the ASBR2, and the PE2 have respectively assigned the

labels

300, 200, and 100 to the route A. As shown in FIG. 3, the VPN routing label allocation method provided by the second embodiment of the present invention includes the following steps:

S301: When detecting that a new VPN route is added to the virtual private network VPN, the PE2 detects the label allocation configuration.

In this embodiment, a new VPN route is added to the VPN2 network connected to the PE2 in FIG. 4, and the address of the new VPN route B is 10.4.0.2; and the label distribution of the VPN2 network is configured to configure each VRF. Label (allocate an ingress label for each VPN routing forwarding table VRF);

S302: The PE2 generates and sends a VPN routing update message according to the label allocation configuration.

Because the label allocation is configured to configure each label of each VRF, the PE needs to obtain the identity of the source public network edge device PE of the new VPN route (that is, the identity of the PE2, such as the establishment address of the PE2: 2.2.2.2 And add it as the public network edge device PE identifier to the VPN routing update message (this message also includes VPN2 RD: 2:1), and then sent to ASBR2;

At the same time, in PE2, the incoming label of the new VPN route B is also 100;

S303: The ASBR2 receives the VPN routing update message, and determines, according to the VPN routing update message, whether to allocate a label for the new VPN route.

Because the ASBR2 needs to send the VPN routing update message to the ASBR1, it is necessary to determine whether to assign a label to the new VPN route. Optionally, step S303 includes:

The ASBR2 detects whether the VPN routing update message carries the PE identifier of the public network edge device.

If it is not carried, it indicates that the label distribution of the VPN network is configured such that each label of each VRF is not configured, and each VPN route needs to be configured with a label, and the label is assigned to the new VPN route.

If it is carried, it indicates that the label distribution of the VPN network is configured with each label of each VRF. In this case, it is necessary to further determine whether the ASBR has assigned a label to the VPN network, that is, perform the next step:

Extracting the PE identifier of the public network edge device and the route identifier RD of the new VPN route, and detecting whether there is a label that matches the PE identifier of the public network edge device and the route identifier RD of the new VPN route. If not, the ASBR is not The VPN network allocates a label. In this case, the label is assigned to the new VPN route. If it exists, the ASBR has already assigned a label to the VPN network. To avoid duplicate labels, the detected label is used as the label of the new VPN route.

In this embodiment, the VPN routing update message sent by the PE2 carries the link-building address (2.2.2.2) and the route identifier RD (2:1) of the PE2. After extracting the parameters, the ASBR2 searches for the parameter and determines whether it is already VPN2 assigns a label. Because ASBR2 has already assigned the ingress label 200 to VPN route A in VPN2, do not repeatedly assign labels to VPN route B, and use the ingress label 200 as the ingress label of the new VPN route B.

S304: ASBR2 allocates a new label to the new VPN route according to the judgment result, or determines a label of the new VPN route.

S305: ASBR2 sends a VPN routing update message to ASBR1, and ASBR1 processes a VPN routing update message.

This step is similar to steps S303 and S304, and will not be described again.

S306: ASBR1 sends a VPN routing update message to PE1, and PE1 processes the VPN routing update. Message

In this embodiment, since PE1 does not need to advertise the routing information of VPN2, it is not necessary to assign a label to the newly added route.

In practical applications, the BGP_PEER table can be set in the ASBR and other transit devices to store the routing information of each VPN network for subsequent data transmission. The optional BGP_PEER table includes: number n (corresponding to VPN network n) , RDn+ source PEn, inbound label n, next hop n, and outgoing label n, then step S303 may be to query whether there is a BGP_PEER table that matches RD (2:1) and source PE (2.2.2.2). If BGP_PEER table n exists, there is no need to assign a label to the new VPN route, and the ingress label n in table n is used as its ingress label. If there is no BGP_PEER table n, the label is assigned. And create a new BGP_PEER table.

The difference between the embodiment of the present invention and related technologies will be described with reference to FIG. 1 and FIG. 4:

As shown in Figure 1, when the VPN2 network connected to PE2 uses the label per VPN label, the route forwarding information of VPN2 on ASBR1 and ASBR2 is the same. It is not necessary to assign different ingress labels to different routes of the VPN2 network. To avoid unnecessary waste. On the ASBR, the source PE address can indicate the PE to which the packet needs to be sent. The RD can indicate the VPN on the PE. Therefore, the RD+ source PE can be used as the destination parameter for private network forwarding. According to this target parameter, it is uniformly forwarded to the destination VPN. Therefore, it is sufficient to assign an inbound label to this target parameter, thereby reducing the number of labels and speeding up the convergence.

As shown in FIG. 4, the basic configuration in the second embodiment of the present invention is: PE1 and ASBR1 are located in AS1, PE2 and ASBR2 are located in AS2, and VPN1 needs to access VPN2 across domains. The RD of VPN2 is 2:1, which has two addresses 10.2.0.1, and 10.4.0.2. In the MP-EBGP networking mode, VPN2 is configured with a per-VPN per-port for the VPN2. The PE2 uses the loopback address 2.2.2.2 to establish a BGP connection with the loopback address 2.1.1.1 of the ASBR2. The ASBR1 is directly connected to the ASBR2 with the directly connected address 5.1.1.1. BGP is established in the IP address of 5.1.1.2. The ASBR1 establishes BGP with the loopack address 1.1.1.2 and the loopback address 1.1.1.1 of the PE1. The LDP tunnel is established between PE1 and ASBR1 and between PE2 and ASBR2.

Then, in this embodiment, the new route advertisement process is: the label assigned to VPN2 on PE2 is 100, and PE2 advertises routes 2:1/10.2.0.1/32 and 2:1/10.4.0.2/32 to ASBR2. ;ASBR2 receives the routing update message and finds the active PE link establishment address 2.2.2.2, so 2:1+2.2.2.2 is established. The BGP_PEER table is assigned to the label 200, and the two VPNv4 routes are advertised to the ASBR1 by the label 200 and the next hop. The ASBR1 receives the VPNv4 route update message and discovers the active PE link establishment address 2.2.2.2, so 2:1 +2.2.2.2 Create a BGP_PEER table, assign it to the label 300, and advertise the two VPNv4 routes with the label 300 and the next hop to PE1. PE1 only needs to import the routing information into VPN1, and does not need to advertise it again. Need to be assigned a label;

On the basis of the label allocation method provided by the embodiment of the present invention, the data forwarding process of the VPN1 to the VPN2 includes: VPN1 sends a data packet to the VPN2, and the PE1 receives the data packet to check the VPN1 private network route, and encapsulates the private network label 300. And the public network tunnel is found according to the next hop 1.1.1.2 of the public network. The public network label is not required to be encapsulated and sent to the ASBR1. The label packet received by the ASBR1 according to the label 300 (BGP_PEER) table is exchanged into the label 200. According to the public network next hop 1.1.1.2, the direct route is found. The public network label is not required to be encapsulated and sent to the ASBR2. The ASBR2 receives the label packet and queries the label table according to the label 200. If you find the public network tunnel, you do not need to encapsulate the public network label and send it to PE2. PE2 receives the label packet and queries the label table. The packet is sent to VPN2. The private network routing table of VPN2 is queried according to the VPNID and IP header. Forward the packet to the destination.

In summary, the embodiments of the present invention have at least the following beneficial effects:

The solution provided by the embodiment of the present invention, after receiving the VPN routing update message, first determines whether a label needs to be allocated for the new VPN route, and only allocates the label when needed, and the related technology is after receiving the VPN routing update message. Compared with the new VPN route distribution label, the number of labels of the VPN route can be reduced, and the pressure of the ASBR is alleviated;

In addition, in the embodiment of the present invention, the RD and the source PE of the VPN network are used to determine whether the label is assigned to the route, that is, the ASBR allocates the same ingress label to the same route as the source PE, and the degree of label reduction can be enhanced.

The above is only a specific embodiment of the present invention, and is not intended to limit the present invention in any way.

One of ordinary skill in the art will appreciate that all or part of the steps of the above embodiments may be used. The computer program can be implemented in a computer readable storage medium, the computer program being executed on a corresponding hardware platform (such as a system, device, device, device, etc.), when executed, including One or a combination of the steps of the method embodiments.

Alternatively, all or part of the steps of the above embodiments may also be implemented by using an integrated circuit. These steps may be separately fabricated into individual integrated circuit modules, or multiple modules or steps may be fabricated into a single integrated circuit module. achieve.

The devices/function modules/functional units in the above embodiments may be implemented by a general-purpose computing device, which may be centralized on a single computing device or distributed over a network of multiple computing devices.

When each device/function module/functional unit in the above embodiment is implemented in the form of a software function module and sold or used as a stand-alone product, it can be stored in a computer readable storage medium. The above mentioned computer readable storage medium may be a read only memory, a magnetic disk or an optical disk or the like.

Industrial applicability

The above technical solution can reduce the number of labels of VPN routes and alleviate ASBR pressure.

Claims

A virtual private network VPN routing label allocation method applied to an autonomous system border router ASBR includes:

Receiving a VPN routing update message;

Determining whether to assign a label to the new VPN route according to the VPN routing update message;

According to the judgment result, a new label is allocated for the new VPN route, or a label of the new VPN route is determined.
The method of claim 1, wherein the determining, according to the VPN routing update message, whether to assign a label to a new VPN route comprises:

Detecting whether the VPN routing update message carries the public network edge device PE identifier, and the public network edge device PE identifier is the identity of the source public network edge device PE of the new VPN route; if the public network edge device PE identifier is not carried, Assign labels to new VPN routes.
The method of claim 2, the method further comprising:

If the public network edge device PE identifier is carried, the public network edge device PE identifier and the new VPN route route identifier RD are extracted, and the route identifier of the public network edge device PE identifier and the new VPN route is detected. The label that matches RD at the same time, if not, assigns a label to the new VPN route. If it exists, the detected label is used as the label of the new VPN route.
The method of claim 2, wherein the identity identifier comprises a chain-building address of the source public network edge device PE.
The method of any of claims 1 to 4, wherein the tag is an incoming tag of the new VPN route.
A virtual private network VPN routing label allocation method applied to a PE of a public network edge device includes:

When it is detected that a new VPN route is added to the virtual private network VPN, the label allocation configuration is detected;

A VPN routing update message is generated and sent according to the label allocation configuration.
The method of claim 6 wherein

The label distribution configuration includes:

Whether to configure each label of each VPN routing forwarding table VRF;

The generating the VPN routing update message according to the label allocation configuration includes: acquiring an identity of the source public network edge device PE of the new VPN route, and adding the public network edge device PE identifier to the VPN In the routing update message.
A virtual private network VPN routing label allocation method includes:

When the public network edge device PE detects that a new VPN route is added to the virtual private network VPN, detecting a label allocation configuration, and generating and sending a VPN routing update message according to the label allocation configuration;

The autonomous system border router ASBR receives and according to the VPN route update message, determines whether to assign a label to the new VPN route, and if necessary, assigns a label to the new VPN route.
An autonomous system border router ASBR, including:

a receiving module, configured to receive a virtual private network VPN routing update message;

a determining module, configured to determine, according to the VPN routing update message, whether to assign a label to a new VPN route; and,

The allocating module is configured to allocate a new label for the new VPN route according to the judgment result, or determine a label of the new VPN route.
A public network edge device PE includes:

The checking module is configured to detect a label allocation configuration when a new VPN route is added to the virtual private network VPN; and

The sending module is configured to generate and send a VPN routing update message according to the label allocation configuration.
A virtual private network VPN routing label allocation system, comprising the autonomous system border router ASBR according to claim 9 and the public network edge device PE according to claim 10.
A computer storage medium having stored therein computer executable instructions for performing the method of any one of claims 1 to 5.
A computer storage medium having stored therein computer executable instructions for performing the method of any one of claims 6-7.
A computer storage medium having stored therein computer executable instructions for performing the method of claim 8.