CN102571375B

CN102571375B - Multicast forwarding method and device as well as network device

Info

Publication number: CN102571375B
Application number: CN201210028817.0A
Authority: CN
Inventors: 张明振
Original assignee: Beijing Star Net Ruijie Networks Co Ltd
Current assignee: Beijing Star Net Ruijie Networks Co Ltd
Priority date: 2012-02-09
Filing date: 2012-02-09
Publication date: 2015-04-22
Anticipated expiration: 2032-02-09
Also published as: CN102571375A

Abstract

The invention provides a multicast forwarding method and a device as well as a network device. The method comprises the following steps: a first PE (Provider Edge) in a first VPN (Virtual Private Network) receives a private network multicast message transmitted by a multicast source in the first VPN; the first PE encapsulates the private network multicast message according to a public network multicast address of MD (Multicast Domain) that the second PE belongs to in the second VPN configured under the MVRF (Multicast Virtual Routing and Forwarding) of the first PE to generate a public network multicast message whose destination address is the public network multicast address of the MD that the second PE belongs to, and transmits the public network multicast message to the second PE so that the second PE restores the public network multicast message into the private network multicast message and then transmits to the second VPN. The technical proposal of the invention ensures that the amount of MT (Multicast Tunnel) established between the VPN and the PE configured on the PE is reduced during VPN multicast spanning, and the resources of VPN and MT are saved.

Description

Multicast forward method, device and the network equipment

Technical field

The present invention relates to the network communications technology, particularly relate to a kind of multicast forward method, device and the network equipment.

Background technology

Multiprotocol label switching (Multiprotocol Label Switching, MPL S) is that one does not re-use conventional routing table and carries out data retransmission, but determines the agreement of forwarding behavior by the label searched in message.Multicasting virtual private network network (Virtual Private Network, VPN) be the technology that a kind of three layers of (L3) MPLS VPN based on Border Gateway Protocol (Border Gateway Protocol, BGP) propagate the multicast packet in VPN.Wherein, multicast domain (Multicast-Domain, MD) is a kind of scheme realizing multicasting VPN, i.e. MD VPN scheme.Each VPN corresponding a MD, this MD cover in this VPN can all Provider edge routers (Provider EdgeRouter, PE) of multicast packet alternately.In MD VPN scheme, MD is regarded as public network, and is regarded as private network outside this MD.Each MD distributes an independently multicast address on public network, be called shared group (Share-Group) address, it is the unique designation of MD on public network, is used for the multicast distribution tree (Multicast Distribution Tree, MDT) set up on public network corresponding to MD.MDT defines the path between each PE of multicast data transmission in MD, comprises default MDT (Default-MDT) and data MDT (DateMDT).In MD, each PE is connected together by Multicast Tunnel (Multicast Tunnel, MT).Multicast Tunnel Interface (Multicast Tunnel Interface, MTI) is the entry/exit mouth of MT, is equivalent to the entry/exit mouth of MD.PE is connected on MT by MTI.Inner at MD, private network data are transmitted by MT.MT transmitting procedure is: private network multicast message is packaged into public network multicast message by local PE, and carries out multicast forwarding in public network, and far-end PE is reduced into private network multicast message by decapsulation after receiving this public network multicast message.

Fig. 1 is a kind of network diagram realizing multicasting VPN in prior art.As shown in Figure 1, PE1, PE2 and convergent point (Rendezvous Point, RP) 3 form MD, and Customer Edge router (CustomerEdge Router, CE) 4 is connected with PE1, and CE5 and PE2 connects.Wherein, CE4 and CE5 belongs to same VPN.In this network architecture, MD is regarded as public network, after the private network multicast message (supposing that the source address of this private network multicast message and destination address are 192.168.1.1 and 224.1.1.1 respectively) in VPN is sent to PE1 by CE4, PE1 is according to corresponding multicasting VPN route forwarding table (MulticastVPN Routing and Forwarding, MVRF) multicast message of private network to be sent on MTI and to be converted to public network multicast message and (suppose that the source address after public network multicast message and destination address are respectively 10.1.1.1, 239.1.1.1), then be sent in MT, other PE (such as PE2) in this MD are transmitted to by MT, public network multicast packet is converted to private network multicast packet by PE2 again.

In actual application, different VPN often can be needed to access the scene of the service of a shared VPN.As shown in Figure 2, the business that the subscriber equipment 21 under a VPN needs the multicast server 27 in access the 2nd VPN to provide, now just there will be the multicast requirement across VPN.Because different VPN corresponds to different MD, and be separate between each MD.The method solved in prior art across VPN multicast is, configuration the 2nd VPN on the PE23 that CE22 in a VPN connects, PE23 is made to belong to the MD of corresponding 2nd VPN by RP24 with the PE25 that the CE26 in the 2nd VPN connects, in this MD, set up MT between each PE, completed the transmission of private network multicast packet by MT.Or, PE25 configures a VPN, makes PE23 and PE25 belong to the MD of a corresponding VPN, between each PE of this MD, set up MT, completed the forwarding of private network multicast packet by MT.

From above-mentioned, in order to the multicast between realizing across VPN, need to configure VPN belonging to the opposing party (this VPN concerning the party PE be do not need exist) on the PE of a side and make two PE belong to a MD, and set up corresponding MT between two PE.But, every platform equipment allow the VPN that configures and the MT number supported to be all limited, effective VPN and MT resource will be reduced like this, cause the waste of VPN and MT resource.

Summary of the invention

The invention provides a kind of multicast forward method, device and the network equipment, in order to the MT quantity set up between realization is across VPN and PE that minimizing PE during VPN multicast configures, save VPN and MT resource.

The invention provides a kind of multicast forward method, comprising:

A PE in one VPN receives the private network multicast message that the multicast source in a VPN sends, and the destination address of described private network multicast message is the private network multicast address of the 2nd VPN;

The public network multicast address of described PE MD belonging to the 2nd PE in described 2nd VPN configured under the MVRF of a described PE in advance, carry out encapsulation process to described private network multicast message and generate public network multicast message, the destination address of described public network multicast message is the public network multicast address of MD belonging to described 2nd PE;

Described public network multicast message is sent to described 2nd PE by the Multicast Tunnel MT between described 2nd PE by a described PE, is forwarded in described 2nd VPN after described public network multicast message being reduced to described private network multicast message to make described 2nd PE.

The invention provides a kind of multicast forwarding device, comprising:

Message receiver module, the private network multicast message that the multicast source for receiving in described multicast forwarding device place the one VPN sends, the destination address of described private network multicast message is the private network multicast address of the 2nd VPN;

Package module, for the public network multicast group address of MD belonging to the multicast forwarding device in described 2nd VPN configured under the MVRF of described multicast forwarding device in advance, carry out encapsulation process to described private network multicast message and generate public network multicast message, the destination address of described public network multicast message is the public network multicast address of MD belonging to the multicast forwarding device in described 2nd VPN;

Sending module, for by the Multicast Tunnel MT between the multicast forwarding device in described multicast forwarding device and described 2nd VPN described public network multicast message being sent to the multicast forwarding device in described 2nd VPN, be forwarded in described 2nd VPN after described public network multicast message being reduced to described private network multicast message to make the multicast forwarding device in described 2nd VPN.

The invention provides a kind of network equipment, comprise arbitrary multicast forwarding device provided by the invention.

Multicast forward method provided by the invention, device and the network equipment, by the public network multicast address of MD belonging to the 2nd PE that configures the 2nd VPN under the MVRF of a PE of a VPN, by a PE, the private network multicast message of the one VPN is encapsulated as the public network multicast message of destination address multicast address of MD belonging to the 2nd PE, then the 2nd PE is sent by the Multicast Tunnel between a PE and the 2nd PE, and then be forwarded to the 2nd VPN after public network multicast message being reduced to private network multicast message by the 2nd PE, achieve the multicast across VPN, and do not need to configure unwanted VPN on a PE or the 2nd PE, the VPN for configuration is not just needed to set up Multicast Tunnel yet, VPN and tunnel resource are saved.

Accompanying drawing explanation

Fig. 1 is a kind of network diagram realizing multicasting VPN in prior art;

Fig. 2 is the network diagram that in prior art, another realizes multicasting VPN;

The flow chart of the multicast forward method that Fig. 3 provides for one embodiment of the invention;

The flow chart of the multicast forward method that Fig. 4 provides for another embodiment of the present invention;

A kind of network diagram of the MD VPN that Fig. 5 provides for one embodiment of the invention;

The structural representation of the multicast forwarding device that Fig. 6 provides for one embodiment of the invention;

The structural representation of the multicast forwarding device that Fig. 7 provides for another embodiment of the present invention;

The structural representation of the multicast forwarding device that Fig. 8 provides for further embodiment of this invention.

Embodiment

The flow chart of the multicast forward method that Fig. 3 provides for one embodiment of the invention.As shown in Figure 3, the method for the present embodiment comprises:

A PE in step 301, a VPN receives the private network multicast message that the multicast source in a VPN sends, and the destination address of described private network multicast message is the private network multicast address of the 2nd VPN.

Wherein, when the multicast service that the user in the 2nd VPN needs the multicast source in access the one VPN to provide, multicast request can be sent to the multicast source in a VPN.Multicast source in one VPN can provide service according to multicast request to the user in the 2nd VPN.Concrete, the private network multicast message that the multicast source in a VPN sends can be transmitted to a PE in a VPN by the CE in a VPN.

In MD VPN scheme, a PE can configure multiple VPN.A PE in one VPN of the present embodiment refers to and to be connected with the CE in a VPN, and is configured with a VPN on the interface be connected with the CE in a VPN.

One PE receives the private network multicast message forwarded by the CE in a VPN.Concrete, private network multicast message is sent to a PE by PIM agreement by the CE in a VPN.

The public network multicast address of step 302, PE MD belonging to the 2nd PE in the 2nd VPN configured under the MVRF of a PE in advance, carry out encapsulation process to private network multicast message and generate public network multicast message, the destination address of described public network multicast message is the public network multicast address of MD belonging to the 2nd PE.

In the present embodiment, the PE in a VPN has been configured with the public network multicast address of MD belonging to the 2nd PE in the 2nd VPN in advance under its MVRF, binds by the public network multicast address of MD belonging to the MVRF of a PE and the 2nd PE.Wherein, the 2nd PE in the 2nd VPN refers to and to be connected with the CE in the 2nd VPN, and is configured with the 2nd VPN on the interface be connected with the CE in the 2nd VPN.In the present embodiment, belonging to the 2nd PE, MD refers to the MD corresponding to the 2nd VPN, and belonging to the 2nd PE, the public network multicast address of MD refers to the multicast address of the MD corresponding to the 2nd VPN.

One PE of the present embodiment does not configure the 2nd VPN, and the 2nd PE of the present embodiment does not configure a VPN, but do not limit on a PE and the 2nd PE can configure other VPN simultaneously.Such as, a PE and the 2nd PE can configure the 3rd VPN simultaneously, that is, a PE and the 2nd PE belongs to the 3rd VPN.

In the present embodiment, one PE configures the public network multicast address of MD belonging to the 2nd PE under its MVRF, after the private network multicast message receiving a VPN, encapsulated the public network multicast address of MD belonging to the address of the loopback interface of a PE and the 2nd PE by the skin at private network multicast message again, generate public network multicast message.Wherein, the address of the loopback interface of a PE refers to that a PE is for setting up the IP address of bgp protocol neighbours, the namely IP address of MTI.

Because a PE is configured with the public network multicast address of MD belonging to the 2nd PE under its MVRF, therefore, one PE after receiving private network multicast message, can as to carrying out the private network multicast message of multicast in a VPN to sending to the private network multicast message of the 2nd VPN to process.Difference is, a PE is the multicast address of the MD that the 2nd VPN is corresponding to the destination address of public network multicast message obtained after sending to the private network multicast message of the 2nd VPN to encapsulate, instead of the multicast address of MD corresponding to a VPN.

Public network multicast message is sent to the 2nd PE by the MT between the 2nd PE by step 303, a PE, is forwarded in the 2nd VPN after public network multicast message being reduced to private network multicast message to make the 2nd PE.

After the private network multicast message in a VPN is encapsulated as public network multicast message, public network multicast message is sent to the 2nd PE by the MT between itself and the 2nd PE by a PE.

2nd PE receives the public network multicast message of a PE transmission by the MT between a PE, then the public network multicast message received is reduced, public network multicast message is reduced to private network multicast message, then according to its MVRF, private network multicast message is forwarded in the 2nd VPN.

In the present embodiment, the MT between a PE and the 2nd PE can be any one article of MT be present between a PE and the 2nd PE.Such as, if a PE and the 2nd PE belongs to the 3rd VPN, then will there is the MT of the MD of one article of correspondence the 3rd VPN between a PE and the 2nd PE, then public network multicast message can be sent to the 2nd PE by this MT by a PE.

If there is not any MT between a PE and the 2nd PE, then a PE can first set up one article of MT with the 2nd PE, then by newly-built MT, public network multicast message is sent to the 2nd PE.

In the present embodiment, one PE is by the public network multicast address of MD belonging to the 2nd PE that configures the 2nd VPN under its MVRF, the private network multicast message of a VPN is encapsulated as the public network multicast message of destination address multicast address of MD belonging to the 2nd PE after receiving the private network multicast message sending to the 2nd VPN, then the 2nd PE is sent by the Multicast Tunnel between a PE and the 2nd PE, and then be forwarded to the 2nd VPN after public network multicast message being reduced to private network multicast message by the 2nd PE, achieve the multicast across VPN, and do not need to configure unwanted VPN on a PE or the 2nd PE, the VPN for configuration is not just needed to set up Multicast Tunnel yet, VPN and tunnel resource are saved.

The flow chart of the multicast forward method that Fig. 4 provides for another embodiment of the present invention.As shown in Figure 4, the method for the present embodiment comprises:

Step 401, a PE configure the public network multicast address of MD belonging to the 2nd PE in advance under the MVRF of a PE, and on a PE, configure the RP in MD belonging to the 2nd PE.

In the present embodiment, following information can be configured under the MVRF of a PE:

Xxx (config-vrf) #mdt default group_address: represent based on default MDT group enable under VRF; Wherein, group_address comprises the multicast address of the multicast address of MD corresponding to a VPN and MD corresponding to the 2nd VPN.Wherein, the default prompt set by " xxx " expression, such as, can be set to the title of each company.

Xxx (config) #ip multicast-routing vrf vrf_name: represent based on VRF multicast enabled agreement.

Xxx (config-if-type ID) #ip pim sparse-mode: represent public network interface enable multicast protocol.

Xxx (config-router) #neighbor ip-address remote-as asn-number: represent and set up IBGP session between PE.

Xxx (config-router) #neighbor ip-address update-source interface-name: for indicating the interface setting up bgp session, for public Multicast Routing.

Xxx (config-router) #address-family ipv4 mdt: represent enable MDT address race.

Xxx (config-router-af) #neighbor ip-address activate: represent and activate bgp neighbor under this address race.

In addition, RP information is provided with for different VPN.Such as, xxx (config) #ip pim [vrfvrf-name] rp-address rp-address [access_list]: represent and determine RP position based on VRF.Wherein, different RP can be set based on different group addresss.In the present embodiment, when the public network multicast address of the MD belonging to configuration the 2nd PE, be configured with the RP corresponding with this public network multicast address simultaneously.

RP in MD belonging to the public network multicast address of MD belonging to the 2nd PE configured under the MVRF of a PE and the 2nd PE that configures on a PE is advertised to the multicast neighbor of a PE by step 402, a PE, and the multicast neighbor of a described PE comprises the 2nd PE.

Wherein, the multicast neighbor of a PE namely " xxx (config-router) #address-family ipv4mdt " this order and subsequent configuration.

One PE is configured with the public network multicast address of MD belonging to the 2nd PE under its MVRF, and be configured with corresponding RP on a PE after, and the public network multicast address of MD belonging to the 2nd configured PE and corresponding RP are advertised to its multicast neighbor.Wherein, the binding relationship of its MVRF and public network multicast address is advertised to its neighbours' multicast by a PE, and in like manner, a PE also can receive the binding relationship of its multicasts neighbor advertisement.In the prior art, a PE and its multicast neighbor are to determine whether set up MT each other by the object of the binding relationship of its MVRF and public network multicast address mutually.In the present embodiment, the binding relationship that a PE and its multicast neighbor notice its MVRF and public network multicast address mutually determines each other whether one of factor setting up MT, in addition, also will consider whether there is MT between a PE and its multicast neighbor.If its MVRF mutually noticed according to a PE and its multicast neighbor and the binding relationship of public network multicast address are determined need each other to set up MT, and when there is MT between a PE and its multicast neighbor, just no longer set up MT.Only determine at the binding relationship of its MVRF mutually noticed according to a PE and its multicast neighbor and public network multicast address and need each other to set up MT, and when there is not MT between a PE and its multicast neighbor, just can set up MT.Such as, if the MVRF of a PE has bound the public network multicast address of MD belonging to the 2nd PE, and the MVRF of the 2nd PE has also bound the public network multicast address of MD belonging to a PE, and still there is not MT between a PE and the 2nd PE, then can set up MT between a PE and the 2nd PE; If the MVRF of a PE has bound the public network multicast address of MD belonging to the 2nd PE, and the MVRF of the 2nd PE has also bound the public network multicast address of MD belonging to a PE, but there is MT between a PE and the 2nd PE, then can not set up MT again between a PE and the 2nd PE.

Concrete, a PE can find its multicast neighbor by bgp protocol, and by the binding relationship of bgp protocol to its multicasts neighbor advertisement MVRF and public network multicast address.

A PE in step 403, a VPN receives the private network multicast message that the multicast source in a VPN sends, and the destination address of described private network multicast message is the private network multicast address of the 2nd VPN.

The public network multicast address of step 404, PE MD belonging to the 2nd PE in the 2nd VPN configured under the MVRF of a PE in advance, carry out encapsulation process to private network multicast message and generate public network multicast message, the destination address of described public network multicast message is the public network multicast address of MD belonging to the 2nd PE.

Public network multicast message is sent to the 2nd PE by the MT between the 2nd PE by step 405, a PE, is forwarded in the 2nd VPN after public network multicast message being reduced to private network multicast message to make the 2nd PE.

Above-mentioned steps 403-step 405 see the description of step 301-step 303, can not repeat them here.

Further, if when there is not MT between a PE and the 2nd PE, a PE and the 2nd PE needs to set up MT.Wherein, the process that a PE and the 2nd PE sets up MT namely sets up the process of DMT.This process of establishing specifically comprises: a PE and the 2nd PE respectively with the RP in MD belonging to the 2nd PE configured on a PE for root, (* is sent to this RP, default mdt) add message to set up RPT, this " default mdt " added in message refers to the public network multicast address of MD belonging to the 2nd PE that configures under the MVRF of a PE.Then, the RP in MD belonging to the 2nd PE that a PE configures with a PE and the 2nd PE for source, can send corresponding (S, default mdt) registration message respectively to a PE and the 2nd PE and forms corresponding SPT.Wherein, " S " in registration message represents the address of a PE or the address of the 2nd PE; " default mdt " in registration message refers to the public network multicast address of MD belonging to the 2nd PE that configures under the MVRF of a PE.So just between a PE and the 2nd PE, establish MDT, also will set up a MT.

A kind of network diagram of the MD VPN that Fig. 5 provides for one embodiment of the invention.As shown in Figure 5, the network of the present embodiment comprises: three VPN, are respectively VPNA, VPNB and VPNC.VPNA comprises multicast source 50, CE51, CE52 and PE53.VPNB comprises subscriber equipment 61, CE62 and PE63.VPNC comprises subscriber equipment 71, CE72 and PE63.PE53 with PE63 is connected by RP60, and PE53, PE63 and PE73 constitute a MD.Wherein, PE73 belongs to another one VPN.

Suppose, the subscriber equipment 61 in VPNB will access the video traffic that the multicast source 50 in VPNA provides.Multicast forwarding flow process then across VPN is as follows:

The multicast address of the MD that VPNB is corresponding on PE63 is configured under the VRF of PE53.PE53 configures the RP of corresponding VPNB.Suppose that the multicast address of the MD that VPNB is corresponding on PE63 is 224.0.1.0.

The private network multicast message of multicast source 50 sends to PE53 through CE51.Suppose that source IP address and the object IP address of private network multicast message are respectively: 10.1.1.2 and 232.0.0.0.Wherein, 10.1.1.2 is the IP address of multicast source 50, and 232.0.0.0 is the private network multicast address of VPNB.

PE53, according to the multicast address of MD corresponding to VPNB on pre-configured PE63, carries out Reseal to private network multicast message, obtains public network multicast message.Suppose source IP address and object IP address 2.2.2.2 and 224.0.1.0 respectively of public network multicast message.Wherein, 2.2.2.2 is the loopback interface address of PE53, and for setting up the address of bgp neighbor, 224.0.1.0 is the multicast address of the MD that on PE63, VPNB is corresponding.

Then, PE53 encapsulates GRE field again, for marking GRE encapsulation, informs that internal layer is IP.Then, PE53 carries out two layers of encapsulation to public network multicast message, such as, encapsulate target MAC (Media Access Control) address 01:00:5e:00:01:00.MAC Address 01:00:5e:00:01:00 is the multicast mac address that multicast address 224.0.1.0 is corresponding.

Then, public network multicast message, by the MT between PE63, is sent to PE63 along MDT between PE53 and PE63 by PE53.

After PE63 receives public network multicast message, public network multicast message is reduced, obtain source IP address and object IP address is respectively: the private network multicast message of 10.1.1.2 and 232.0.0.0, is forwarded to private network multicast message in VPNB.

In VPMB, private network multicast message finally arrives subscriber equipment 61 through CE62.

Wherein, the private network multicast message of multicast source 50 comprised before CE51 sends to PE53: the process of subscriber equipment 61 order video business.The process of subscriber equipment 61 order video business is: certain multicast channel of subscriber equipment 61 program request, can send IGMP add message to gateway device.IGMP adds message is transmitted to this VPNB PE63 through gateway device.PE63 can continue to send IGMP to the RP in VPNB and add message.Concrete, this IGMP can be added message encapsulation in gre tunneling message by PE63, forms public network multicast message, is transmitted to corresponding PE53 by MT.PE53 can carry out decapsulation to this gre tunneling message, and is transmitted to the RP equipment in VPNA according to VPN information, the final RPT forming this VPNA, thus achieves subscriber equipment 61 to multicast source 50 video on demand service.

In sum, the multicast forward method that various embodiments of the present invention provide solves needs the extra VPN quantity increasing configuration on entrance or outlet PE, effectively make use of limited precious resources, take full advantage of the tunneling mechanism that same VPN inside is set up, avoid the quantity due to the newly-increased tunnel introduced across VPN function, effectively make use of valuable tunnel resource.The multicast forward method that various embodiments of the present invention provide is disposed relative simple, understandable with enforcement, effectively reduces maintenance cost and workload.

The structural representation of the multicast apparatus that Fig. 6 provides for one embodiment of the invention.As shown in Figure 6, the device of the present embodiment comprises: message receiver module 611, package module 621 and sending module 631.

Wherein, message receiver module 611, the private network multicast message that the multicast source for receiving in multicast forwarding device place the one VPN of the present embodiment sends, the destination address of described private network multicast message is the private network multicast address of the 2nd VPN.

Package module 621, be connected with message receiver module 611, for the public network multicast group address of MD belonging to the multicast forwarding device in the 2nd VPN configured under the MVRF of the multicast forwarding device of the present embodiment in advance, the private network multicast message received message receiver module 611 carries out encapsulation process and generates public network multicast message, and the destination address of described public network multicast message is the public network multicast address of MD belonging to the multicast forwarding device in the 2nd VPN.

Sending module 631, be connected with package module 621, public network multicast message for being packaged into by package module 621 by the MT between the multicast forwarding device in the multicast forwarding device of the present embodiment and the 2nd VPN sends to the multicast forwarding device in the 2nd VPN, is forwarded in the 2nd VPN after public network multicast message being reduced to private network multicast message to make the multicast forwarding device in the 2nd VPN.

The multicast forwarding device of the present embodiment is configured with a VPN, but there is no configuration the 2nd VPN.Multicast forwarding device in the multicast forwarding device of the present embodiment and the 2nd VPN belongs to different VPN.

Each functional module of the multicast forwarding device of the present embodiment can be used for the flow process performing multicast forward method shown in Fig. 3, and its specific works principle repeats no more, and refers to the description of embodiment of the method.

Wherein, the multicast forwarding device in the multicast forwarding device of the present embodiment or the 2nd VPN can be the PE in MD VPN scheme, but is not limited thereto.

The multicast forwarding device of the present embodiment, by the public network multicast address of MD belonging to the multicast forwarding device in the 2nd VPN pre-configured under its MVRF, after the private network multicast message in the VPN receiving place, belonging to the multicast forwarding device in the 2nd pre-configured VPN, private network multicast message is encapsulated as the public network multicast message of destination address public network multicast address of MD belonging to the multicast forwarding device in the 2nd VPN by the public network multicast address of MD, thus under not configuring on the multicast forwarding device of the present embodiment the 2nd VPN or the multicast forwarding device in the 2nd VPN not configuring the condition of a VPN, public network multicast message is sent to the multicast group retransmission unit in the 2nd VPN, achieve the multicast across VPN, and do not need to configure unwanted VPN on two multicast forwarding devices, the VPN for configuration is not just needed to set up Multicast Tunnel yet, VPN and tunnel resource are saved.

The structural representation of the multicast forwarding device that Fig. 7 provides for another embodiment of the present invention.The present embodiment is based on realization embodiment illustrated in fig. 6, and as shown in Figure 7, the device of the present embodiment also comprises: configuration module 641 and announcement module 651.

Wherein, configuration module 641, be connected with package module 621, for the public network multicast group address at package module 621 MD belonging to the multicast forwarding device in the 2nd VPN configured under the MVRF of the multicast forwarding device of the present embodiment, the private network multicast message received message receiver module 611 carries out before encapsulation process generates public network multicast message, the public network multicast address of MD belonging to the multicast forwarding device in the 2nd VPN is configured in advance under the MVRF of the multicast forwarding device of the present embodiment, and the RP configured on the multicast forwarding device of the present embodiment in MD belonging to the multicast forwarding device in the 2nd VPN.

Announcement module 651, be connected with configuration module 641, RP in MD belonging to multicast forwarding device in the public network multicast address and the 2nd VPN that configures on multicast forwarding device of MD belonging to the multicast forwarding device in the 2nd VPN configured under the MVRF of configuration module 641 at multicast forwarding device is advertised to the multicast neighbor of multicast forwarding device, and the multicast neighbor of described multicast forwarding device comprises the multicast forwarding device in the 2nd VPN.

Above-mentioned functions module can be used for perform embodiment illustrated in fig. 4 in corresponding flow process, its specific works principle repeats no more, and refers to the description of embodiment of the method.

Further, the sending module 631 of the present embodiment comprises: first sends submodule 6311 and second sends submodule 6321.

Wherein, first sends submodule 6311, be connected with package module 621, during for having there is MT between the multicast forwarding device in the multicast forwarding device and the 2nd VPN of the present embodiment, the public network multicast message be directly packaged into by package module 621 sends to the multicast forwarding device in the 2nd VPN by the MT existed, be forwarded in the 2nd VPN after public network multicast message being reduced to private network multicast message to make the multicast forwarding device in the 2nd VPN.

Second sends submodule 6321, be connected with package module 621, during for there is not MT between the multicast forwarding device in the multicast forwarding device and the 2nd VPN of the present embodiment, with the newly-built MT of multicast forwarding device in the 2nd VPN, and the public network multicast message be packaged into by package module 621 sends to the multicast forwarding device in the 2nd VPN by newly-built MT, be forwarded in the 2nd VPN after this public network multicast message being reduced to private network multicast message to make the multicast forwarding device in the 2nd VPN.

Further, second of the present embodiment sends submodule 6321 and sends (* specifically for the RP in MD belonging to the multicast forwarding device in the 2nd VPN configured on the multicast forwarding device of the present embodiment, the public network multicast address of MD belonging to multicast forwarding device in 2nd VPN) add message to set up RPT, and be received in (the S that the RP in MD belonging to the multicast forwarding device in the 2nd VPN that the multicast forwarding device of the present embodiment configures sends, the public network multicast address of MD belonging to multicast forwarding device in 2nd VPN) registration message to be to set up SPT, thus new MT is set up between the multicast forwarding device in the multicast forwarding device and the 2nd VPN of the present embodiment.Wherein, S is the address of the multicast forwarding device of the present embodiment.

The multicast forwarding device of the present embodiment, the public network multicast address of MD belonging to the multicast forwarding device realizing on multicast forwarding device in pre-configured 2nd VPN by configuration module and announcement module and correspondingly RP, lay the foundation for setting up Multicast Tunnel between the multicast forwarding device in the multicast forwarding device and the 2nd VPN of the present embodiment.

The structural representation of the multicast forwarding device that Fig. 8 provides for further embodiment of this invention.The present embodiment is based on realization embodiment illustrated in fig. 7, the multicast forwarding device of the present embodiment not only can as the device of multicast source place VPN, be responsible for the private network multicast message in the requestor's forwarding multicasting source in another VPN, the multicast forwarding device of the present embodiment can also as the device in the VPN of multicast request person place, and the multicast request to multicast source forwarding multicasting requestor is also responsible for the private network multicast message of the multicast source that the device in the place VPN of receiving group source forwards.Namely the multicast forwarding device of the present embodiment can also as the multicast forwarding device in the 2nd VPN.

As shown in Figure 8, the multicast apparatus of the present embodiment also comprises: information receiving module 711 and set up module 721.

Wherein, information receiving module 711, for receive that multicast forwarding device in a VPN notices the multicast forwarding device being configured in the present embodiment under the MVRF of the multicast forwarding device in a VPN belonging to the public network multicast group address of MD and the present embodiment on being configured in a VPN multicast forwarding device multicast forwarding device belonging to RP in MD.

Set up module 721, be connected with information receiving module 711, RP in MD belonging to the multicast forwarding device of the present embodiment configured on the multicast forwarding device in a VPN received to information receiving module 711 sends (*, the public network multicast group address of MD belonging to the multicast forwarding device of the present embodiment) add message to set up RPT, and (the S that the RP in MD belonging to the multicast forwarding device being received in the present embodiment that the multicast forwarding device in a VPN configures sends, the public network multicast address of MD belonging to the multicast forwarding device of the present embodiment) registration message to be to set up SPT, thus set up new Multicast Tunnel with the multicast forwarding device in a VPN.Wherein, S is the address of the multicast forwarding device of the present embodiment.

Further, the multicast forwarding device of the present embodiment also comprises: recovery module 731.

Recovery module 731, the public network multicast message that the multicast forwarding device for receiving in a VPN sends, and be forwarded in the 2nd VPN after public network multicast message is reduced to private network multicast message.

Above-mentioned each functional module can be used for performing Fig. 3 or embodiment illustrated in fig. 4 in flow process corresponding to multicast forwarding device in the 2nd VPN, its specific works principle repeats no more, and refers to the description of embodiment of the method.

The multicast forwarding device of the present embodiment can be the PE in MD VPN scheme, but is not limited thereto.

The multicast forwarding device of the present embodiment is as the device in the 2nd VPN, match with the multicast forwarding device in a VPN, achieve the multicast across VPN, and unwanted VPN need not be configured thereon, just do not need to set up unwanted Multicast Tunnel, saved VPN and tunnel resource yet.

In this explanation, multicast forwarding device in the VPN that the embodiment of the present invention provides and the multicast forwarding device in the 2nd VPN can be separate, namely the multicast forwarding device that the above embodiment of the present invention provides only can have the function of the multicast forwarding device in a VPN, also only can have the function of the multicast forwarding device in the 2nd VPN.

One embodiment of the invention provides a kind of network equipment, comprises arbitrary multicast forwarding device that the above embodiment of the present invention provides.

The network equipment of the present embodiment can be the PE in MD VPN scheme, but is not limited thereto.

The multicast forwarding device that the network equipment of the present embodiment provides owing to comprising the embodiment of the present invention, can be used for the flow process performing the multicast forward method that the embodiment of the present invention provides equally, when realizing the multicast across VPN, can save VPN and tunnel resource equally.

One of ordinary skill in the art will appreciate that: all or part of step realizing above-mentioned each embodiment of the method can have been come by the hardware that program command is relevant.Aforesaid program can be stored in a computer read/write memory medium.This program, when performing, performs the step comprising above-mentioned each embodiment of the method; And aforesaid storage medium comprises: ROM, RAM, magnetic disc or CD etc. various can be program code stored medium.

Last it is noted that above each embodiment is only in order to illustrate technical scheme of the present invention, be not intended to limit; Although with reference to foregoing embodiments to invention has been detailed description, those of ordinary skill in the art is to be understood that: it still can be modified to the technical scheme described in foregoing embodiments, or carries out equivalent replacement to wherein some or all of technical characteristic; And these amendments or replacement, do not make the essence of appropriate technical solution depart from the scope of various embodiments of the present invention technical scheme.

Claims

1. a multicast forward method, is characterized in that, comprising:

Described public network multicast message is sent to described 2nd PE by the Multicast Tunnel MT between described 2nd PE by a described PE, be forwarded to after described public network multicast message being reduced to described private network multicast message to make described 2nd PE in described 2nd VPN, wherein, described MT is present in the MT that any MT between an a described PE and described 2nd PE or described PE and described 2nd PE sets up in advance.

2. multicast forward method according to claim 1, it is characterized in that, described public network multicast message is sent to described 2nd PE by the Multicast Tunnel MT between described 2nd PE by a described PE, is forwarded in described 2nd VPN and comprises after described public network multicast message being reduced to described private network multicast message to make described 2nd PE:

If there is MT between a described PE and described 2nd PE, described public network multicast message is directly sent to described 2nd PE by the MT existed by a described PE, is forwarded in described 2nd VPN after described public network multicast message being reduced to described private network multicast message to make described 2nd PE;

If there is not MT between a described PE and described 2nd PE, a described PE and the newly-built MT of described 2nd PE, and described public network multicast message is sent to described 2nd PE by newly-built MT, be forwarded in described 2nd VPN after described public network multicast message being reduced to described private network multicast message to make described 2nd PE.

3. multicast forward method according to claim 2, it is characterized in that, the public network multicast address of described PE MD belonging to the 2nd PE in described 2nd VPN configured under the MVRF of a described PE in advance, carries out comprising before encapsulation process generates public network multicast message to described private network multicast message:

A described PE configures the public network multicast address of MD belonging to described 2nd PE in advance under the MVRF of a described PE, and on a described PE, configure the RP in MD belonging to described 2nd PE;

RP in MD belonging to the public network multicast address of MD belonging to the 2nd PE configured under the MVRF of a described PE and described 2nd PE that configures on a described PE is advertised to the multicast neighbor of a described PE by a described PE, and the multicast neighbor of a described PE comprises described 2nd PE.

4. multicast forward method according to claim 3, is characterized in that, a described PE and the newly-built MT of described 2nd PE comprises:

A described PE and described 2nd PE sends respectively to the RP in MD belonging to described 2nd PE configured on a described PE and adds message to set up RPT;

(the S that RP in MD belonging to described 2nd PE that a described PE and described 2nd PE to be received on a described PE configuration respectively sends, the public network multicast address of MD belonging to described 2nd PE) registration message to be to set up SPT, wherein, S is the address of a described PE or the address of described 2nd PE.

5. a multicast forwarding device, is characterized in that, comprising:

Sending module, for by the Multicast Tunnel MT between the multicast forwarding device in described multicast forwarding device and described 2nd VPN described public network multicast message being sent to the multicast forwarding device in described 2nd VPN, be forwarded to after described public network multicast message being reduced to described private network multicast message to make the multicast forwarding device in described 2nd VPN in described 2nd VPN, wherein, described MT is present in the MT that any MT between a PE and a 2nd PE or described PE and described 2nd PE sets up in advance.

6. multicast forwarding device according to claim 5, is characterized in that, described sending module comprises:

First sends submodule, during for having there is MT between the multicast forwarding device in described multicast forwarding device and described 2nd VPN, directly described public network multicast message is sent to the multicast forwarding device in described 2nd VPN by the MT existed, be forwarded to after described public network multicast message being reduced to described private network multicast message to make the multicast forwarding device in described 2nd VPN in described 2nd VPN;

Second sends submodule, during for there is not MT between the multicast forwarding device in described multicast forwarding device and described 2nd VPN, with the newly-built MT of multicast forwarding device in described 2nd VPN, and described public network multicast message is sent to the multicast forwarding device in described 2nd VPN by newly-built MT, be forwarded in described 2nd VPN after described public network multicast message being reduced to described private network multicast message to make the multicast forwarding device in described 2nd VPN.

7. multicast forwarding device according to claim 6, is characterized in that, also comprises:

Configuration module, for configuring the public network multicast address of MD belonging to the multicast forwarding device in described 2nd VPN in advance under the MVRF of described multicast forwarding device, and on described multicast forwarding device, configure the RP in MD belonging to the multicast forwarding device in described 2nd VPN;

Announcement module, RP in MD belonging to multicast forwarding device in the public network multicast address and described 2nd VPN that configures on described multicast forwarding device of MD belonging to the multicast forwarding device in described 2nd VPN configured under the MVRF of described multicast forwarding device is advertised to the multicast neighbor of described multicast forwarding device, and the multicast neighbor of described multicast forwarding device comprises the multicast forwarding device in described 2nd VPN.

8. multicast forwarding device according to claim 7, it is characterized in that, described second sends submodule adds message to set up RPT specifically for the RP transmission in MD belonging to the multicast forwarding device in described 2nd VPN configured on described multicast forwarding device, and be received in (the S that the RP in MD belonging to the multicast forwarding device in described 2nd VPN that described multicast forwarding device configures sends, the public network multicast address of MD belonging to multicast forwarding device in described 2nd VPN) registration message to be to set up SPT, wherein, S is the address of described multicast forwarding device.

9. a multicast forwarding device, is characterized in that, comprising:

Message receiver module, for the private network multicast message that the multicast source in the VPN of receiving group retransmission unit place the one sends, the destination address of described private network multicast message is the private network multicast address of the 2nd VPN;

Sending module, for by the Multicast Tunnel MT between the multicast forwarding device in described multicast forwarding device and described 2nd VPN described public network multicast message being sent to the multicast forwarding device in described 2nd VPN, be forwarded to after described public network multicast message being reduced to described private network multicast message to make the multicast forwarding device in described 2nd VPN in described 2nd VPN, wherein, described MT is present in the MT that any MT between a PE and a 2nd PE or described PE and described 2nd PE sets up in advance;

Information receiving module, for receive that multicast forwarding device in a described VPN notices the described multicast forwarding device being configured under the MVRF of the multicast forwarding device in a described VPN belonging to RP in MD belonging to the public network multicast group address of MD and described multicast forwarding device on being configured in a described VPN multicast forwarding device;

Set up module, RP for receiving to described information receiving module sends and adds message to set up RPT, and be received in (the S that the RP in MD belonging to described multicast forwarding device that the multicast forwarding device in a described VPN configures sends, the public network multicast address of MD belonging to described multicast forwarding device) registration message to be to set up SPT, wherein, S is the address of the multicast forwarding device in described 2nd VPN.

10. multicast forwarding device according to claim 9, is characterized in that, also comprises:

Recovery module, the public network multicast message that the multicast forwarding device for receiving in a described VPN sends, and be forwarded in described 2nd VPN after described public network multicast message is reduced to private network multicast message.

11. 1 kinds of network equipments, is characterized in that, comprise the multicast forwarding device described in any one of claim 5-10.