Inter-network Ethernet Service Protection

1. Inter-network Ethernet Service Protection Zehavit Alon Nurit Sprecher John Lemon

2. Agenda • Inter-network Ethernet Service Protection • Overview • Requirements • Network architecture • Possible connectivity constructions between Ethernet Networks • Recommended construction • Proposed solution • Open discussion and next steps

3. PB PB PBB PBB-TE PBB-TE Ethernet Services over Interconnected Networks • Carrier Ethernet services are delivered over interconnected Ethernet networks - untagged, C-VLAN, S-VLAN, B-VLAN • Interconnected networks may, for example, consist of: • a customer’s network connected to a service provider's network • that is also connected to other service providers' networks. • An end-to-end carrier Ethernet service can span several interconnected packet networks.

4. PB PB PBB PBB-TE PBB-TE Interconnected Zone Interconnected Zone Interconnected Zone Interconnected Zone Ethernet Services over Interconnected Networks • Each Ethernet network may deploy a different packet transport technology which provides its own mechanisms aimed at ensuring network survivability. Examples are: • Bridged Ethernet with MSTP or SPB or G.8032 • Traffic Engineered Ethernet with PBB-TE protection switching • A protection mechanism is required for the interconnected zone. PB xSTP 1:1 SPB 1:1 PB xSTP

5. Interconnected Networks Protection Mechanism: Requirements • Protect against any single failure or degradation of a facility (link or node) in the interconnected zone • Support all standard Ethernet frames: 802.1D, 802.1Q, 802.1ad, 802.1ah • Support interconnection between different network types (e.g. CN-PBN, PBN-PBN, PBN-PBBN, PBBN-PBBN, etc.) • Provide 50ms protection switching • Provide a clear indication of the protection state • Maintain an agnostic approach towards: • the Ethernet technology running on each of the interconnected networks, and • the protection mechanism deployed by each of the interconnected networks

6. Interconnected Networks Protection Mechanism: Requirements (cont’d.) • Avoid modification of the protocols running inside each of the interconnected networks • Ensure that multicast and broadcast frames are delivered only once over the interconnected zone • Allow load balancing between the interfaces that connect the networks to ensure efficient utilization of resources

7. Mesh Ring Possible Topologies

8. Dual Attached Connectivity

9. Enhanced Resiliency Dual attachment is widely deployed.

10. A B D C Connectivity between adjacent networks A D C B

11. Protection Path Load

12. Load Sharing

13. Protection Path Cost Working Protection

14. Multiple Failures No traffic No traffic No traffic

15. Interconnection with Rings (G.8032) Shared Link G.8032 G.8032

16. Proposed Topologies • Mesh that supports dual-homing and that provides enhanced protection in the double dual-homing configuration

17. 5 C 6 Solution Principles Blue traffic (VLAN X) is only sent through port 1 (which is protected by port 2). Blue traffic is sent through port 2 in the event of failure of link 1-3, or of node B Interconnect zone 3 B 1 A 4 2 7 D 8 Blue traffic is sent through node C in the event that node A fails. • The protection mechanism is available per Ethernet service in the interconnected zone (i.e. per VLAN). • An Ethernet service is carried only over one of the interfaces which connects the two adjacent networks. • In the event of a fault condition on the link or the peer node, traffic is redirected to the redundant interface. • The service may also be protected by another node to avoid a single point of failure. If a node is no longer able to carry traffic, traffic is redirected over the redundant node.

18. 5 C 6 F E Solution Principles Interconnect Area 3 B 1 A 4 2 10 9 7 D 8 11 11 12 13 • The interconnected zone may include additional nodes, interfaces and links • Each protected VLAN is configured, (independently of other VLANs) on: • Total of three nodes and four ports - on one of the networks, one node with two ports; on the other network, two nodes with one port on each (i.e. dual-homing) • Total of four nodes and eight ports - on both networks, two nodes with two ports each (i.e double dual-homing) • Each protected VLAN can be transmitted over one out of two/four links. However, at any given time, it is only transmitted over one of the links crossing the interconnected zone.

19. The role of each node (master, deputy and slave) is set for each VLAN by administrative configuration. • The same node may function as a master node for some VLANs (blue), as a deputy node for other VLANs (red), and a slave for other VLANs (green), thus enabling load sharing between the nodes. Solution Principles • For each protected VLAN, one of the nodes is responsible for selecting the interface over which the traffic will be transmitted. This node functions as a master. • The master is connected to two nodes. These two nodes follow the master’s decisions and function as slaves. • The master node can be protected by a redundant node. In the event that the master fails, the redundant node functions as the master. This node is called a deputy. The deputy is connected to the same two slaves as the master. S D S D M S S M S M D S

20. Solution Principles • For each VLAN, the master/deputy/slave nodes are configured according to the following options: • Additional parameters must be configured for the master and deputy nodes (not for the slaves): • working port – the default port to use for traffic • protection port – the port to use when the working port can not be used.

21. 1 5 3 S1 M D 2 6 4 7 S2 8 Solution Principles • The interface selection algorithm for each VLAN is based on • local configuration • Information provided by link-level CCMs • The protection state of all the protected VLANs is synchronized between peers by means of a single link-level CCM message. Slave1 follows master’s decision and uses port 3 for VLAN X Master chooses the configured working port 1 for VLAN X Master uses this port for VLAN X Slave1 uses this port for VLAN X Master uses another port for VLAN X Slave1 is active, and uses another port for VLAN X. Slave2 follows master’s decision and does not use any of its ports for VLAN X Master is working so deputy does not need to take over Slave2 is not active for VLAN X Deputy is not active for VLAN X Deputy is not active for VLAN X Slave2 is not active for VLAN X

22. 5 D M 6 Solution Principles • If a link fails, the master node uses the protection port (port 2) for VLAN X Link on port 1 is not working, Master chooses the configured protection port 2 for VLAN X Slave1 does not receive anything from the master. It does not use any of its ports for VLAN X 1 3 S1 Master uses this port for VLAN X 2 4 Slave is not active for VLAN x Slav2 follows master’s decision and uses port 7 for VLAN X Master is working so deputy does not need to take over Deputy is not active for VLAN X 7 Slave2 uses this port for VLAN X S2 Deputy is npot active for VLAN X 8 Slave2 is actctive and uses another port for VLAN X

23. M D Solution Principles • If the master fails, the deputy is informed about it by the slaves and it becomes active Does not receive anything from master so it doesn't use any port for VLAN X Master failed. Does not send anything does not use any of its ports for VLAN X 1 3 S1 Slave1 does not work for VLAN X Slave1 does not work for VLAN X 2 4 Deputy sees that both slaved are not working. It understands that the master is not working so deputy takes over using its working port (6) Does not receive anything from master so it doesn't use any port for VLAN Deputy uses another port for VLAN X 5 7 S2 Slave2 follows deputy’s decision and uses port 8 for VLAN X 6 Deputy uses this port for VLAN X 8 Slave2 does not work for VLAN X Slave2 uses this this port for VLAN X

24. Solution Principles • A protected VLAN x is defined on 2 ports: On port A, VLAN x is configured as working entity, while on port B, VLAN x is configured as protection entity • In a live system, the VLAN is transmitted only on one of the ports (working or protection entity). • The 2 ports on which the VLAN is protected are grouped into a VLAN Protection Group (VPG). The VPG is a logical bridge port (as defined in 802.1Q + ad + ah). Port A Port B VLAN x Working VLAN x Protection Port A Port B VLAN x VLAN x VPG Port A Port B VLAN x VLAN x

25. VPG Port A Port B VLAN x VLAN x Solution Principles • The VPG forwards VLAN traffic to the port selected by the algorithm. • VLAN traffic received on a port is forwarded to the VPG. Learning occurs at the VPG level. • The CCMs are sent and received by ports A and B, and the selection algorithm is implemented on the VPG, based on the information received on both ports. VPG Port A Port B VLAN x VLAN x

26. Solution Principles Location of the new shim

27. Intention • Start a new project in the IEEE802.1 aimed at defining a protection mechanism for interconnected networks in the proposed topologies. The mechanism should comply with the requirements introduced in this presentation. • Decide whether we should send a liaison to the MEF in order to receive feedback on (1) the proposed connectivity construction and (2) the requirements.

28. Thank You zehavit.alon@nsn.com nurit.sprecher@nsn.com jlemon@ieee.org