Method and apparatus for MPLS label allocation for a BGP MAC-VPN

1. A method for distributing flooding labels within a Multiprotocol Label Switching (MPLS) infrastructure supporting Border Gateway Protocol (BGP) Media Access Control (MAC) Virtual Private Networking (VPN), the method comprising:

generating, at a destination provider edge (PE) router, a generic flooding label (GFL) for each MAC-VPN Instance (MVI) that is advertising network layer reachability information (NLRI);

generating, at the destination PE router, a Multi-Homing Flooding Label (MHFL) for each designated forwarder (DF) Ethernet Segment Identifier (ESI) that is advertising NLRI; and

transmitting, toward one or more source PE routers, each generated GFL and MHFL using MAC-VPN Network Layer Reachability Information (NLRI) including a Route-Distinguisher (RD) and an ESI;

generated GFLs being configured to cause each of said one or more source PE routers to replicate and forward toward the destination PE router broadcast/unknown unicast/multicast (BUM) traffic received via any attachment circuit (AC) according to a corresponding GFL transmitted by the destination PE router.

2. The method of claim 1 , further comprising:

generated MHFLs being configured to cause the one or more source PE routers to tag BUM traffic entering on non-DF ACs of ESI with a corresponding MHFL distributed by the destination PE router.

3. The method of claim 1 , further comprising:

at a source PE router, replicating and forwarding toward the destination PE router all broadcast/unknown unicast/multicast (BUM) traffic received via any attachment circuit (AC) according to a corresponding GFL distributed by the destination PE router; and

at the source PE router, tagging BUM traffic entering on non-DF ACs of ESI with a corresponding MHFL distributed by the destination PE router.

4. The method of claim 1 , further comprising:

at the destination PE router, flooding to all local MVI endpoints any packet received on a point to multi-point label switched path (P2MP LSP).

5. The method of claim 4 , wherein packets received via non-DF attachment circuits (ACs) are not flooded to local MVI endpoints.

6. The method of claim 1 , further comprising:

at a source PE router, for each MVI that is advertising NLRI, generating an NLRI using an inclusive multicast Virtual Local Area Network Route-Target (VLAN RT) format.

7. The method of claim 6 , wherein the inclusive multicast VLAN RT format comprises a Route-Distinguisher (RD) of the MVI, an ESI, an Ethernet tag and an originating router Internet Protocol (IP) address.

8. The method of claim 1 , further comprising:

at a source PE router, generating a respective MHFL for each non-DF ESI that is advertising NLRI.

9. The method of claim 8 , wherein the NLRI includes an Ethernet segment Route-Target (RT) format comprising a Route-Distinguisher (RD), a specific ESI, the corresponding MHFL and an originating router's Internet Protocol (IP) address.

10. The method of claim 9 , wherein the Ethernet segment RT format further comprises a P-tunnel attribute.

11. The method of claim 8 , further comprising:

at the destination PE router, flooding to all local MVI endpoints any packet received on a point to multi-point label switched path (P2MP LSP).

12. The method of claim 11 , wherein packets received via non-DF attachment circuits (ACs) are not flooded to local MVI endpoints.

13. A method for routing traffic through a Multiprotocol Label Switching (MPLS) network, the method comprising:

generating, at a destination provider edge (PE) router, a generic flooding label (GFL) for each MAC-VPN Instance (MVI) that is advertising network layer reachability information (NLRI);

generating, at the destination PE router, a Multi-Homing Flooding Label (MHFL) for each designated forwarder (DF) Ethernet Segment Identifier (ESI) that is advertising NLRI; and

transmitting, toward one or more source PE routers, each generated GFL and MHFL using MAC-VPN Network Layer Reachability Information (NLRI) including a Route-Distinguisher (RD) and an ESI;

generated GFLs being configured to cause each of said one or more source PE routers to replicate and forward toward the destination PE router broadcast/unknown unicast/multicast (BUM) traffic received via any attachment circuit (AC) according to a corresponding GFL transmitted by the destination PE router.

14. A non-transitory computer readable storage medium comprising computer instructions which, when processed by a computer, configure the operation of the computer to provide a method for distributing flooding labels within a Multiprotocol Label Switching (MPLS) infrastructure supporting Border Gateway Protocol (BGP) Media Access Control (MAC) Virtual Private Networking (VPN), the method comprising:

generating, at a destination provider edge (PE) router, a generic flooding label (GFL) for each MAC-VPN Instance (MVI) that is advertising network layer reachability information (NLRI);

generating, at the destination PE router, a Multi-Homing Flooding Label (MHFL) for each designated forwarder (DF) Ethernet Segment Identifier (ESI) that is advertising NLRI; and

transmitting, toward one or more source PE routers, each generated GFL and MHFL using MAC-VPN Network Layer Reachability Information (NLRI) including a Route-Distinguisher (RD) and an ESI;

generated GFLs being configured to cause each of said one or more source PE routers to replicate and forward toward the destination PE router broadcast/unknown unicast/multicast (BUM) traffic received via any attachment circuit (AC) according to a corresponding GFL transmitted by the destination PE router.

15. The computer readable storage medium of claim 14 , said method further comprising:

at a source PE router, replicating and forwarding toward the destination PE router all broadcast/unknown unicast/multicast (BUM) traffic received via any attachment circuit (AC) according to corresponding GFL advertised by the destination PE router.

16. The computer readable storage medium of claim 15 , said method further comprising:

at the source PE router, tagging BUM traffic entering on non-DF ACs of ESI with a corresponding MHFL distributed by the destination PE router.

17. The computer readable storage medium of claim 14 , said method further comprising:

at the destination PE router, flooding to all local MVI endpoints any packet received on a point to multi-point label switched path (P2MP LSP).

18. The computer readable storage medium of claim 14 , said method further comprising:

at the destination PE router, flooding to all local MVI endpoints any packet received on a point to multi-point label switched path (P2MP LSP), wherein packets received via non-DF attachment circuits (ACs) are not flooded to local MVI endpoints.

19. The computer readable storage medium of claim 14 , said method further comprising:

at a source PE router, for each MVI that is advertising NLRI, generating an NLRI using an inclusive multicast VLAN RT format, wherein the inclusive multicast VLAN RT format comprises a Route-Distinguisher (RD) of the MVI, an ESI, an Ethernet tag and an originating router IP Address.

20. A method for distributing flood labels within a Multiprotocol Label Switching (MPLS) infrastructure supporting Border Gateway Protocol (BGP) Media Access Control (MAC) Virtual Private Networking (VPN), the method comprising:

receiving, at a source provider edge (PE) router and via MAC-VPN Network Layer Reachability Information (NLRI) including a Route-Distinguisher (RD) and an Ethernet Segment Identifier (ESI), a generic flooding label (GFL) for each MAC-VPN Instance (MVI) that is advertising NLRI, each GFL having been generated by a respective destination PE router;

receiving, at the source PE router and via MAC-VPN NLRI including a RD and an ESI, a Multi-Homing flooding label (MHFL) for each designated forwarder (DF) ESI that is advertising NLRI, each MHFL having been generated by a respective destination PE; and

at the source PE router, replicating and forwarding toward a respective destination PE router all broadcast/unknown unicast/multicast (BUM) traffic received via any attachment circuit (AC) according to a GFL from the respective destination PE router.

21. The method of claim 20 , further comprising:

tagging, at the source PE router, BUM traffic entering on non-DF ACs of ESI according to a MHFL from the respective destination PE router.

22. The method of claim 20 , further comprising:

for each MVI that is advertising NLRI, generating at the source PE router an NLRI using an inclusive multicast Virtual Local Area Network Route-Target (VLAN RT) format.

23. The method of claim 22 , wherein the inclusive multicast VLAN RT format comprises a Route-Distinguisher (RD) of the MVI, an ESI, an Ethernet tag and an originating router Internet Protocol (IP) address.

24. The method of claim 20 , further comprising:

generating, at the source PE router, a respective MHFL for each non-DF ESI that is advertising NLRI.

25. The method of claim 24 , wherein the NLRI includes an Ethernet segment Route-Target (RT) format comprising a Route-Distinguisher (RD), a specific ESI, the corresponding MHFL and an originating router Internet Protocol (IP) address.

26. The method of claim 25 , wherein the Ethernet segment RT format further comprises a P-tunnel attribute.