WO2008040240A1 - The method and device for outbound route filter based on bgp - Google Patents

Abstract

A method, a transmitting device and a receiving device for outbound route filter based on BGP are disclosed. In the embodiment, the information receiver of the BGP peer advertises the Nexthop ORF policy to the corresponding route information transmitter. The route information transmitter returns the Nexthop route information in accordance with the Next ORF policy to the route information receiver according to the Next ORF policy. Said method and device availably resolve the problem that the current ORF can not filter the route based on the Nexthop route. Moreover, the configuration is simplified greatly and the complexity that BGP processes the ORF is also simplified.

Description

 Method and device for outgoing route filtering based on BGP protocol

 The present invention relates to communication technologies, and in particular, to a method and apparatus for outgoing route filtering based on the BGP protocol. Background of the invention

 Border Gateway Protocol (BGP) is widely deployed in today's Internet networks to transfer large amounts of routing information between autonomous systems (ASs) and ASs. The routing information needs to be first connected between the routers through the BGP protocol. The two routers that establish BGP connections are each other's neighbors (BGP peers). Also, for the same router, the router may have more than one neighbor. The BGP peer uses the TCP protocol as the transport layer protocol. The default port number is 179, which is used to carry various BGP packet information: including UPDATE and KEEPALIVE. When there are a large number of routes between BGP peers. Between the neighbors, the KEEPALIVE timeout may occur. In this case, the neighbors may not be able to send the KEEPALIVE and the connection between the neighbors is invalid. BGP will perform the neighbor disconnection process, thus causing the route to oscillate. Because the location of the BGP router on the Internet is very important, the route flapping caused by BGP may cause instability of the entire Internet. Therefore, reducing the route flapping caused by BGP can greatly help the stability of the entire Internet.

ORF (Outbound route filter) is a technique used to reduce unnecessary route delivery between BGP peers. The basic idea of the ORF is as follows: The receiving end of the routing information in the BGP peer is advertised to the sending end of the routing information in the BGP peer by filtering the filtering conditions of the relevant routing. The transmitting end first sends the route to the receiving end according to the receiving end. The route filtering condition is sent to filter related routes, and only the filtering conditions of the route are met. The route is sent to the receiving end, which reduces the transmission of "unwanted" routing information between BGP peers, thereby reducing the probability of KEEPALIVE timeout between BGP peers and reducing the oscillation of BGP routes.

 The IDR Working Group of the Internet Engineering Task Force (IETF) has been based on Community attributes, Ext-Community attributes, AS-Paths, and Address Prefixes. ) ORF.

 The ORF based on the Community and Ext-Community is used to perform route filtering for the Community and Ext-Community attributes of the route, that is, the receiving end sends the constraint about the Community and Ext-Community to the corresponding sending end; accordingly, the sending end is configured according to The community, Ext-Community filters the routes and sends only the routes that meet the conditions to the receiver. Based on the Community, the Ext-Community ORF solution is mainly used in the L3 VPN/L2VPN scenario. The Ext-Community is used to carry the routing target (RT) information of the VPN route. The receiving end determines the RT-related constraints. The sender sends a route based on the relevant RT information.

 The AS-Path-based ORF, that is, the receiver establishes an AS-Path-related constraint, and tells the corresponding sender to send a route to the AS-Path-related constraint.

 The address prefix-based ORF, that is, the receiving end tells the corresponding sender to send only the route that satisfies the Address Prefix condition to the receiving end.

The above existing ORF schemes cannot fully meet the actual requirements in the actual networking. If they are limited to these ORF schemes, the network deployment is limited and the configuration is complicated. Summary of the invention

 The embodiment of the present invention provides a route filtering method based on the BGP protocol, and performs route filtering on the routes between the BGP peers according to the next hop information of the route, and configures the path filtering filtering to improve the flexibility of network deployment.

 A method for routing filtering based on BGP protocol includes the following steps:

 The routing information receiving end of the border gateway routing protocol neighbor BGP peer advertises the next hop route filtering Nexthop ORF policy to the routing information sending end in the BGP peer; the receiving end receives the sending end that is sent by the sending end Next hop routing information for the Nexthop ORF policy.

 A method for routing filtering based on BGP protocol includes the following steps:

 The routing information sending end of the BGP peer receives the Nexthop ORF policy advertised by the routing information sender in the BGP peer;

 The sending end sends the next hop routing information that meets the Nexthop ORF policy to the receiving end.

 Correspondingly, the embodiment of the present invention further provides a routing information receiving device for routing filtering based on the BGP protocol, where the receiving device includes: an advertising unit and a first receiving unit, where the advertising unit is configured to filter the next hop route The Nexthop ORF policy is advertised to the routing information sending end in the BGP Peer where the receiving device is located;

 The first receiving unit is configured to receive the next hop routing information that is sent by the sending end and that meets the Nexthop ORF policy.

 The embodiment of the present invention further provides a routing information sending device for outgoing route filtering based on the BGP protocol, including: a second receiving unit and a routing unit, where

a second receiving unit, configured to receive a next hop route filtering Nexthop ORF policy advertised by the routing information receiving end in the BGP peer, and transmit the Nexthop ORF policy to the routing unit; a routing unit, configured to send next hop routing information that meets the Nexthop ORF policy to the receiving end.

 The technical solution provided by the embodiment of the present invention can perform route filtering according to the Nexthop of the route, which can effectively reduce unnecessary route transmission, reduce route oscillation, and can be configured in a centralized manner, and can also implement ORF processing in BGP. The complexity. The technical solution of the embodiment of the present invention can reduce the transmission of unnecessary routes and reduce route oscillations, especially in a network environment where a route transmitter and a multi-homing are deployed. BRIEF DESCRIPTION OF THE DRAWINGS

 1 is a schematic diagram of outgoing route filtering based on the BGP protocol of the present invention;

 2 is a flowchart of a method for routing routing based on BGP protocol according to an embodiment of the present invention; FIG. 3 is a schematic diagram of a routing information receiving device based on BGP protocol according to an embodiment of the present invention; FIG. 4 is a BGP based embodiment according to an embodiment of the present invention; Schematic diagram of the routing information sending device of the protocol. Mode for carrying out the invention

The embodiment of the invention provides a method and device for outgoing route filtering based on the BGP protocol. In the embodiment of the present invention, the routing information receiving end of the BGP peer is configured to generate an outgoing route filtering policy based on the next hop, that is, a Nexthop ORF policy, and then send the outgoing routing filtering policy to the routing information sending end of the BGP peer. The sender sends only the routing information that conforms to the Nexthop ORF policy to the corresponding receiving end according to the received Nexthop ORF policy. Obviously, in practical applications, a router can be either the sender of the routing information or the receiver of the routing information, that is, when the router acts as the sender of the routing information, the router can serve as the routing information sending end; the router acts as a route. When the receiver of the information and the sender of the routing policy, the router can serve as the receiving end of the routing information. And, a receiving end can Similarly, a plurality of transmitting ends are respectively configured as BPG peers; similarly, one transmitting end may also form a BGP peer with multiple receiving ends respectively.

 In the embodiment of the present invention, in order to support the Nexthop-based ORF, a new type of BGP ORF needs to be added. In the embodiment of the present invention, the BGP protocol is extended correspondingly, that is, the BGP protocol is extended to support the capability negotiation of the Nexthop ORF.

 Specifically, an ORF type, that is, a Nexthop ORF type, may be added to the original BGP protocol. The specific value of the filtering type may be assigned by the Internet Assigned Numbers Authority (I AN A). The value is 66;

In the embodiment of the present invention, for the new Nexthop ORF type, a new ORF entity packet format is defined to carry the Nexthop outgoing route filtering condition corresponding to the Nexthop ORF policy. To match the existing ORF common message format, the new ORF entity message format can include the following fields: Action field, which can be represented by three values, such as: Indicates the addition (Add), which is used to indicate that the Nexthop outgoing route filtering condition corresponding to the Nexthop ORF policy specified by the receiving end of the routing information is added to the ORF list of the routing information sending end; the value 1 indicates the deletion, which is used to indicate The Nexthop outgoing route filtering condition specified by the routing information receiving end is deleted in the ORF list of the routing information sending end; the value 2 indicates that all (Remove-all) is deleted, that is, the original ORF list related to the receiving end of the routing information in the routing information sending end is All Nexthop outgoing route filtering conditions are deleted; the filtering field Match, the field can be represented by two values to indicate different meanings, and 0 can be used to indicate permission (Permit), that is, the routing information sending end can send the corresponding Nexthop outgoing route filtering condition. Routing; 1 means Deny, which means that the routing information sender does not need to send the content. Outlet by the routing information should Nexthop filters. The fields included in the ORF entity message can be placed in the general header of the ORF. The general message format of the ORF is already in the IDR working group draft of the IETF. [Outbound Route Filtering Capability for BGP-4] is defined in the format shown in Table 1:

 + +

 I Action (2 bits) I

+ +

 I Match (1 bit) I

+ +

 I Reserved (5 bits) I

 + +

 I Type specific part (variable) I

 Table 1

 In the embodiment of the present invention, the Type specific part field of the ORF entity field may be a variable length field. The Type specific part may include the following fields: a 4-byte Sequence field, which is used to indicate the specific location of the Nexthop ORF entity; a 1-byte Length field, which is used to specify the specificity of the Nexthop field. Length value; Variable length Nexthop field, the specific length of this field can be specified by Length.

 The specific format of the ORF entity field can be as shown in Table 2:

 + +

 I Sequence (4 octets)

 + +

 I Length (1 octet)

 + +

 I Nexthop (variable length)

 + +

Table 2 It should be noted that the position and length of the field are not limited to the above settings, but may be arbitrarily set according to the needs of the actual application. In the specific implementation, the serial number field is an optional field.

 In the embodiment of the present invention, after the BGP protocol is extended, the BGP-based Nexthop ORF policy can be used to perform route filtering. Referring to FIG. 1, FIG. 1 is a schematic diagram of outgoing route filtering based on BGP protocol according to an embodiment of the present invention. In Figure 1, B and C are BGP peers. The two routers can establish BGP neighbor relationships through BGP. If Router B wants to receive the route with the next hop 1.1.1.1 and does not want to receive the route with the next hop being 2.2.2.2, Router B can use 1.1.1.1 as the Nexthop outgoing route filter for the Nexthop ORF policy. After being sent to the router C, the router C sends a route with the next hop 1.1.1.1 to the router B, and the next hop is 2.2.2.2. The route will not be sent to Router B.

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

 Referring to FIG. 2, FIG. 2 is a flowchart of a method for outgoing route filtering based on the BGP protocol in the embodiment of the present invention.

 Step 201: The routing information sending end of the BGP peer performs the ORF capability negotiation with the routing information receiving end.

In this embodiment, the receiving end and the transmitting end respectively send the capability information of the Nexthop ORF supported by the receiving end to the other party, and the other party matches the capability information of the Nexthop ORF supported by the two parties. If the matching is successful, the negotiation succeeds. , the result of the negotiation. As an example, the capability of the receiving end and the sending end is negotiated. When the neighboring relationship is established with the sending end, the receiving end can carry the capability information of the Nexthop ORF supported by the receiving end through the existing Open (Open) message. The Open packet is sent to the sending end. After the neighboring relationship is established between the receiving end and the sending end, the existing dynamic capability negotiation packet carries the supported Nexthop ORF. Capability information; Similarly, the sender can also carry the capability information of the Nexthop ORF supported by the Open message or the dynamic capability negotiation message.

 The capability information of the Nexthop ORF supported by the sending end or the receiving end may include: supporting sending Nexthop ORF packets, supporting receiving Nexthop ORF packets, or both; for example, between B and C routers in FIG. 1 Negotiation of the Nexthop ORF capability. For Router B as the routing information receiving end and Route C as the routing information sending end, the resulting receiving end can send the Nexthop ORF packet carrying the Nexthop ORF policy to the transmitting end, and the transmitting end can receive The result of the negotiation of the Nexthop ORF packet may include: Router B only sends the Nexthop ORF packet, and Router C only receives the Nexthop ORF packet; or, Router B supports both the Sending Next ORF packet and the Nexthop ORF packet, Router C. It can support the sending and receiving of the Nexthop ORF packet. For the router C as the routing information receiving end and the routing B as the routing information sending end, the obtained transmitting end can receive the negotiation of the Nexthop ORF packet carrying the Nexthop ORF policy sent by the receiving end. The results can include: Router B only receives Nexth The op ORF packet, the router C only sends the Nexthop ORF packet; or the router B supports both the sending of the Nexthop ORF packet and the receiving of the Nexthop ORF packet, and the router C can support sending and receiving the Nexthop ORF packet. If the negotiation fails, Router B and Router C cannot process the ORF.

 In addition, the Nexthop ORF packet can be in the form of a separate packet. The information of the Nexthop ORF packet can be carried in other packets. Other packets, such as route refresh packets.

 Step 202: The receiving end generates a Nexthop ORF packet including the Nexthop ORF policy according to the negotiation result of the capability negotiation with the sending end, and sends the packet to the sending end.

In the embodiment of the present invention, the receiving end may send a Nexthop ORF message, and the sending end may receive a Nexthop ORF message. The receiving end can generate Nexthop according to its own Nexthop ORF policy. The ORF message can then be sent to the corresponding sender along with the route refresh message. For example, in Figure 1, Router B wants to receive the route with the next hop being 1.1.1.1, and does not want to receive the route with the next hop being 2.2.2.2. Router B generates the Nexthop ORF entity content, indicating that Router C is interested in Router B's Nexthop. The Nexthop ORF filter condition corresponding to the ORF policy is to allow the route to receive 1.1.1.1. In the Nexthop ORF packet sent by Router B, the Action is 0, indicating that the current Nexthop ORF filter condition needs to be added to the ORF list; Match is 1. Indicates that the receiving router C is allowed to send the route that meets the added filtering condition, that is, 1.1.1.1 in the Nexthop field; the serial number is 1, the length is 4 bytes, and the Nexthop field is 1.1.1.1, then the entity message can be Refer to Table 3:

+ +

 I 00 I

 + +

 I 1 I

 + +

 I Reserved (5 bits) I

 + +

 I 1 I

 + +

 I 4 I

 + +

 I 1.1.1.1 I

 + +

 table 3

Step 203: After receiving the Nexthop ORF packet sent by the receiving end, the sending end sends the routing information that conforms to the Nexthop ORF policy, and is received by the receiving end. In the embodiment of the present invention, the routing information sending end of the Nexthop ORF policy, such as the router C, performs corresponding processing according to the received Nexthop ORF entity message, for example, first updating the outbound route filtering condition in the ORF list according to the Action field. Including: If the action indication is added, the Nexthop outgoing route filtering condition corresponding to the Nexthop ORF policy is added to the ORF list; if the Action indicates deletion, the corresponding Nexthop outgoing route filtering condition is deleted from the local ORF list; If all are deleted, all the Nexthop outgoing route filtering conditions sent by Router B to be deleted are deleted. For example, in Figure 1, Router C adds 1.1.1.1 to the Nexthop outgoing route filtering condition sent by Router B according to 1.1.1.1. In the ORF list;

 Then, when the sending end advertises the route to the receiving end, the sending end needs to perform corresponding filtering operations on the route to be sent according to the Match field in the ORF list, which may include: Match indicates Permit, and then matches the Nexthop outgoing route filtering condition. The routing information is sent to the receiving end; the match indicates Deny, and the routing information matching the Nexthop outgoing route filtering condition is prohibited from being sent to the receiving end. For example, in Figure 1, Router C only sends the route with the next hop 1.1.1.1 to Router B.

 Referring to FIG. 3, FIG. 3 is a schematic diagram of a BGP-based routing information receiving apparatus according to an embodiment of the present invention. The receiving apparatus may be a routing information receiving end in the BGP peer, and may include: an advertising unit and a first receiving unit;

 An advertising unit, configured to advertise a Nexthop ORF policy to a routing information sending end in a BGP peer where the receiving device is located;

 The first receiving unit is configured to receive the next hop routing information that is sent by the sending end and is consistent with the Nexthop ORF policy.

The receiving device may further include: a negotiating unit, configured to perform ORF capability negotiation with the sending end, to obtain that the receiving device can send the Nexthop ORF message carrying the Nexthop ORF policy to the sending end, and the sending end can receive the Nexthop ORF The result of the negotiation of the message. The foregoing negotiating unit may include: a capability information transceiving unit and a matching unit,

 The capability information transceiver unit is configured to send capability information including the Nexthop ORF supported by the receiver to the sender, and receive capability information of the Nexthop ORF supported by the sender sent by the sender;

 The matching unit is configured to match the capability information of the Nexthop ORF supported by the receiving device with the capability information of the Nexthop ORF supported by the transmitting end, and obtain the foregoing negotiation result.

 The notification unit may include: a message generating unit and a first sending unit; wherein

 a message generating unit, configured to generate a Nexthop ORF message including a Nexthop ORF policy according to the foregoing negotiation result, and a Nexthop ORF policy, and send the generated Nexthop ORF message to the first sending unit;

 The first sending unit is configured to receive a Nexthop ORF message from the message generating unit, and send the Nexthop ORF>3⁄4 text to the sending end.

 Referring to FIG. 4, FIG. 4 is a schematic diagram of a BGP-based routing information sending apparatus according to an embodiment of the present invention. The apparatus may be a routing information sending end in the BGP peer, and may include: a second receiving unit and a routing unit, where

 The second receiving unit is configured to receive the routing information receiving end in the BGP peer, that is, the next hop route filtering Nexthop ORF policy advertised by the receiving device in FIG. 3, and transmit the Nexthop ORF policy to the routing unit;

 The routing unit is configured to send the next hop routing information that conforms to the Nexthop ORF policy to the routing information receiving end in the BGP peer.

 The sending device may further include: a negotiating unit, configured to perform ORF capability negotiation with the receiving end, to obtain that the sending device can receive the negotiation result of the Nexthop ORF message carrying the Nexthop ORF policy sent by the receiving end.

The negotiating unit may include: a capability information transceiving unit and a matching unit; The capability information transceiver unit is configured to send capability information including the Nexthop ORF supported by the sending device to the receiving end, and receive the receiving end and the receiving end supports the receiving end

Nexthop ORF capability information;

 The matching unit is configured to match the capability information of the Nexthop ORF supported by the transmitting device with the capability information of the Nexthop ORF supported by the receiving end, and obtain the foregoing negotiation result.

 The routing unit may include: a message receiving unit, a list updating unit, and a second sending unit;

 a packet receiving unit, configured to receive a Nexthop ORF message carrying a Nexthop ORF policy from the receiving end, and send the message to the list updating unit;

 a list update unit, configured to update an outbound route filter condition in the ORF list according to the Nexthop ORF message, and send the updated ORF list to the second sending unit;

 And a second sending unit, configured to receive the ORF list from the list updating unit, and send the next hop routing information to the receiving end according to the outbound routing filtering condition in the updated ORF list.

 The transmitting device and the receiving device may be respectively disposed on different routers or on the same router.

 In a specific implementation, the routing information that needs to be sent by the routing information sending end may meet multiple routing filtering conditions, such as the requirements of the community attribute, the address prefix, and the next hop outgoing route filtering condition. After receiving the routing policy advertised by the receiving end of the routing information, the sending end performs the operation of the filtering condition on the item by item, so that the routing information that meets all the filtering conditions is sent to the receiving end to achieve the maximum configuration policy.

The technical solution provided by the embodiment of the present invention, according to the Nexthop policy, performs routing filtering on the routing information to be sent by the BGP-based routing information sending end, which can effectively reduce unnecessary route transmission and reduce route oscillation, such as deploying route transmission. , multi-homing, etc. In the network environment, the technical solution provided by the embodiment of the present invention can be used, and on the one hand, the configuration can be greatly simplified, and on the other hand, the complexity of BGP processing in BGP can be optimized. In addition, if BGP supports the function of sending multiple routes, that is, BGP can advertise multiple next hop routes to its neighbors, the number of routes to be advertised can be greatly increased, and the technical solution provided by the embodiment of the present invention can be avoided. The sending of unnecessary routes in this application scenario reduces the oscillation of the route.

 The above is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto, and any person skilled in the art can easily think of changes or replacements within the technical scope of the present invention. All should be covered by the scope of the present invention.

Claims

Claim  A method for filtering outbound routes based on the BGP protocol, which is characterized by the following steps:  The routing information receiving end of the border gateway routing protocol neighbor BGP peer advertises the next hop route filtering Nexthop ORF policy to the routing information sending end in the BGP peer; the receiving end receives the sending end that is sent by the sending end Next hop routing information for the Nexthop ORF policy.  The method according to claim 1, wherein before the receiving end advertises the Nexthop ORF policy to the sending end, the method further includes:  The receiving end and the sending end perform the ORF capability negotiation, and the receiving end can send the Nexthop ORF message carrying the Nexthop ORF policy to the sending end, and the sending end can receive the Nexthop ORF report. The result of the negotiation.  The method according to claim 2, wherein the step of the ORF capability negotiation between the receiving end and the sending end comprises:  The receiving end sends the capability information of the Nexthop ORF that is supported by the receiving end to the sending end, and receives the capability information of the Nexthop ORF supported by the sending end sent by the sending end, which is supported by the receiving end. The capability information of the Nexthop ORF is matched with the capability information of the Nexthop ORF supported by the sender.  The method according to claim 3, wherein the capability information comprises: supporting sending a Nexthop ORF message, supporting receiving a Nexthop ORF message, or supporting sending and receiving a Nexthop ORF message.  The method according to claim 4, wherein the negotiation result comprises: the receiving end supports sending a Nexthop ORF message, and the sending end supports receiving Nexthop ORF4 ;文; or, The receiving end supports receiving and sending a Nexthop ORF message, and the sending end supports receiving and sending a Nexthop ORF message.  The method according to claim 3, 4 or 5, wherein the step of the receiving end transmitting the capability information including the Nexthop ORF supported by the receiving end to the sending end comprises:  When the receiving end establishes a neighbor relationship with the sending end, the receiving end carries the capability information that the receiving end can support in the Open Open message, and sends the information to the sending end; or  After receiving the neighbor relationship with the sending end, the receiving end carries the capability information that the receiving end can support in the dynamic capability negotiation packet, and sends the capability information to the sending end.  The method according to claim 2, wherein the step of the receiving end advertising the Nexthop ORF policy to the sending end comprises:  The receiving end generates the Nexthop ORF packet according to the negotiation result and the own Nexthop ORF policy, and sends the Nexthop ORF packet to the sending end.  A method for filtering outbound routes based on the BGP protocol, which is characterized by the following steps:  The routing information sending end of the BGP peer receives the Nexthop ORF policy advertised by the routing information sender in the BGP peer;  The sending end sends the next hop routing information that meets the Nexthop ORF policy to the receiving end. The method according to claim 8, wherein before the sending end sends the next hop routing information to the receiving end, the method further includes: The transmitting end and the receiving end perform the ORF capability negotiation, and the result that the sending end can receive the negotiation result of the Nexthop ORF packet carrying the Nexthop ORF policy sent by the receiving end.  The method according to claim 9, wherein the step of the ORF capability negotiation between the sending end and the receiving end comprises:  The sending end sends the capability information of the Nexthop ORF that is supported by the sending end to the receiving end, and receives the capability information of the Nexthop ORF supported by the receiving end sent by the receiving end, which is supported by the sending end. The capability information of the Nexthop ORF is matched with the capability information of the Nexthop ORF supported by the receiver.  The method according to claim 10, wherein before the sending end sends the next hop routing information to the receiving end, the method further includes:  The sending end updates the outbound route filtering condition in the ORF list of the sending end according to the Nexthop ORF policy carried in the Nexthop ORF packet.  The method according to claim 11, wherein the step of updating the outbound route filtering condition in the ORF list of the sending end comprises:  The sending end updates the outbound route filtering condition in the ORF list according to the content of the action Action field in the Nexthop ORF message.  A routing information receiving device for outgoing route filtering based on the BGP protocol, comprising: an advertising unit and a first receiving unit;  The advertising unit is configured to notify the next hop routing filtering Nexthop ORF policy to the routing information sending end in the BGP peer where the receiving device is located;  The first receiving unit is configured to receive the next hop routing information that is sent by the sending end and that meets the Nexthop ORF policy. The receiving apparatus according to claim 13, wherein the receiving apparatus further includes: a negotiating unit, configured to perform ORF capability negotiation with the transmitting end, to obtain a The receiving device can send the Nexthop ORF message carrying the Nexthop ORF policy to the sending end, and the sending end can receive the negotiation result of the Nexthop ORF message The receiving apparatus according to claim 14, wherein the negotiating unit comprises: a capability information transceiving unit and a matching unit,  The capability information transceiver unit is configured to send capability information including the Nexthop ORF supported by the receiving end to the sending end, and receive capability information of the Nexthop ORF supported by the sending end sent by the sending end;  The matching unit is configured to match the capability information of the Nexthop ORF supported by the receiving device with the capability information of the Nexthop ORF supported by the transmitting end, and obtain the negotiation result.  The receiving device according to claim 14 or 15, wherein the advertising unit comprises: a message generating unit and a first sending unit;  a message generating unit, configured to generate a Nexthop ORF message including the Nexthop ORF policy according to the negotiation result and the Nexthop ORF policy, and send the generated Nexthop ORF message to the first sending unit;  The first sending unit is configured to receive the Nexthop ORF4 message from the message generating unit, and send the Nexthop ORF message.  A routing information sending device for routing filtering based on the BGP protocol, comprising: a second receiving unit and a routing unit, where  a second receiving unit, configured to receive a next hop route filtering Nexthop ORF policy advertised by the routing information receiving end of the BGP peer, and transmit the Nexthop ORF policy to the routing unit; a routing unit, configured to send next hop routing information that meets the Nexthop ORF policy to the receiving end. The transmitting device according to claim 17, wherein the transmitting device further comprises: a negotiating unit, configured to perform ORF capability negotiation with the receiving end, to obtain that the sending device is capable of receiving the receiving end The result of the negotiation of the Nexthop ORF message carrying the Nexthop ORF policy.  The transmitting apparatus according to claim 18, wherein the negotiating unit comprises: a capability information transceiving unit and a matching unit,  The capability information transceiver unit is configured to send capability information including the Nexthop ORF supported by the sending device to the receiving end, and receive capability information of the Nexthop ORF supported by the receiving end sent by the receiving end;  The matching unit is configured to match the capability information of the Nexthop ORF supported by the sending device with the capability information of the Nexthop ORF supported by the receiving end, and obtain the negotiation result.  The transmitting device according to claim 17, 18 or 19, wherein the routing unit comprises: a message receiving unit, a list updating unit, and a second sending unit; wherein the message receiving unit is configured to receive a Nexthop ORF message carrying the Nexthop ORF policy from the receiving end, and transmitting the message to the list updating unit;  a list updating unit, configured to update an outbound filtering condition in the ORF list according to the Nexthop ORF message, and send the updated ORF list to the second sending unit;  And a second sending unit, configured to receive the ORF list from the list updating unit, and send the next hop information to the receiving end according to the outbound routing filtering condition in the updated ORF list.