1. TRILL OAM & BFD draft-eastlake-trill-rbridge-bfd-00.txt Donald E. Eastlake 3 rd 155 Beaver Street Milford, MA 01757 USA November 20101TRILL OAM & BFD Vishwas Manral IP Infusion Vishwas.IETF @gmail.com

2. Contents TRILL OAM – Layer 3 and Layer 2 OAM don’t work for TRILL A TRILL OAM Channel TRILL BFD Support November 2010TRILL OAM & BFD2

3. Operations, Administration, & Management TRILL OAM operates in single and multiple hops between and through TRILL protocol stacks on RBridges. It needs to provide: – Rapid RBridge/link failure detection – TRILL error reporting (TRILL Header hop count exhausted, egress nickname unreachable, …) and similar “ICMP-like” functions – RBridge level traceroute – RBridge level ping OAM November 20103TRILL OAM & BFD

4. Layer 3 OAM Doesn’t Work for TRILL RBridges are not required to have IP protocol stacks or IP addresses. Even if all RBridges in a campus did have IP protocol stacks, those stacks would not be involved in TRILL ingress, transit, or egress processing even for IP native frames. Internet Protocol specific OAM does not meet the needs of TRILL. November 20104TRILL OAM & BFD OAM

5. Layer 2 OAM Doesn’t Work for TRILL Layer 2 OAM would only be applicable to the Layer 2 link between neighbor RBridges. – It could test the link and the ports but would not test the TRILL protocol stacks – Layer 2 protocols, such as Spanning Tree or 802.1ag OAM, cannot pass through and are blocked by RBridges November 20105TRILL OAM & BFD OAM

6. Layer 2 OAM Doesn’t Work for TRILL Different links in an RBridge campus can be different technologies. – For example, all, some, or none of the links in a campus could be PPP or 802.1 or MPLS or other… Layer 2 specific OAM, particularly 802.1ag, does not work for an RBridge campus. – This is one of the arguments that Shortest Path Bridging advocates use against TRILL, that TRILL cannot use 802.1 OAM and requires new OAM facilities. November 20106TRILL OAM & BFD OAM

7. Operations, Administration, & Management OAM November 20107TRILL OAM & BFD Router Bridge RBridge P = Ports and Fast Path Logic ET = Ethernet stack possibly with 802.1ag OAM = Green TR = TRILL protocol stack including TRILL OAM = Red IP = IP protocol stack including Layer 3 OAM = Black P P P P ET IP TR ET Router P ET IP RBridge P TR ET

8. A TRILL OAM Channel TRILL OAM frames look like TRILL Data frames – If unicast they are routed to the egress nickname A special nickname Any-RBridge is available to guarantee delivery to neighbors regardless of the state of nicknames. – If multi-destination, they are distributed over the tree identified by the egress nickname to all RBridges in the Inner.VLAN November 2010TRILL OAM & BFD8

9. A TRILL OAM Channel TRILL OAM frames are detected by an OAM- aware egress RBridge based on their Inner.MacDA and/or Ethertype. – The following Special Inner.MacDAs will be available: Unicast: OAM-RBridge-MAC Multicast: All-OAM-RBridges – The following Ethertype will be available: TRILL-OAM November 2010TRILL OAM & BFD9

10. A TRILL OAM Channel TRILL OAM Frames are TRILL Data Frames: The TRILL OAM Header and Payload are as follows: November 2010TRILL OAM & BFD10 Link HeaderTRILL HeaderOAM HeaderOAM DataLink Trailer Special Inner.MacDA Inner MacSA TRILL-OAM Ethertype Flags, Version, OAM Protocol # OAM Protocol Specific

11. A TRILL OAM Channel 0 = Silent 1 = Multi-Hop 2 - 15 available 1 = OAM Channel Err 2 = BFD Control 3 = BFD Echo 4 – 4,094 available November 2010TRILL OAM & BFD11 Special Inner.MacDA Inner MacSA TRILL-OAM Ethertype Flags, Version, OAM Protocol # OAM Protocol Specific 16 bits of OAM Header Flags 12 bit OAM Protocol Number 4 bit OAM Header Version

12. TRILL BFD Support BFD Control protocol provides very low overhead continuity testing messages. Because of this low overhead, they can be sent frequently and thus rapidly detect failures. For RBridge OAM, BFD Control is sent via the TRILL OAM Channel. November 2010TRILL OAM & BFD12

13. TRILL BFD Support If support for BFD Echo is indicated through BFD Control, BFD Echo can be used to send a frame to a neighbor RBridge that is addressed back to yourself. That is, the ingress and egress nicknames in the TRILL Header are equal. See RFC 5880 and 5882 for general BFD information, RFC 5881 for BFD over IP. November 2010TRILL OAM & BFD13

14. END Donald E. Eastlake 3 rd 155 Beaver Street Milford, MA 01757 USA November 201014TRILL OAM & BFD Vishwas Manral IP Infusion Vishwas.IETF @gmail.com