Presentation on theme: "MPLS-TP BFD for CC-CV proactive and RDI functionalities"— Presentation transcript:
1MPLS-TP BFD for CC-CV proactive and RDI functionalities draft-asm-mpls-tp-bfd-cc-cv-01MPLS WG, 76th IETF - Hiroshima,JapanMPLS-TP 76th IETF - Hiroshima11
2Authors Annamaria Fulignoli (Ericsson) Sami Boutros (Cisco Systems ) Martin Vigoureux (Alcatel-Lucent)
3From IETF75 Merging announcement of the 2 existing drafts draft-fulignoli-mpls-tp-bfd-cv-proactive-and-rdidraft-boutros-mpls-tp-cc-cvinto draft-asm-mpls-tp-bfd-cc-cv
4Goals of draftExtend BFD for proactive Connection Verification and Reverse Defect IndicationRemain Backwards CompatibleSpecify Interoperability
5RequirementsContinuity Check: monitors the integrity of the continuity of the path;Connectivity Verification: monitors the integrity of the routing of the path between sink and sourceDetect unintended connectivity (e.g. mismerging or misconnection)RDI: enable an End Point to report a fault or defect condition that it detects on a PW, LSP or SectionMUST operate proactively for:bidirectional and unidirectional p2punidirectional p2mp connection
6Solution Overview Two modes of operation CC Existing ACH codepoint (0x0007) - BFD w/o IP/UDPSupports CC & RDICV/CCNew ACH codepointHeader contains the Source MEP Identifier (unique per transport path)BFD control packet format is identical to CC modeSupports CV & RDI (Implicit CC)Both apply to PWs, MPLS LSPs (including tandem connection monitoring), and sections
7Overview Operating mode is Asynchronous BFD state machine is defined in draft-ietf-bfd-base-09 for p2p bidirectional transport and in draft-katz-ward-bfd- multipoint-02 for unidirectional p2p and p2mp transport path.BFD session is declared Down if :an unexpected MEP identifier is received (mis- connectivity defect; in CV mode only)timer and detect multiplier re-negotiation is disabled and an unexpected desired min Tx interval field value or unexpected detect multiplier field are received (Unexpected period defect).BFD session times out (Loss of Connectivity defect)77
8BFD Session in MPLS-TP terminology A BFD session corresponds to a CC or a proactive CV/CC OAM instance in MPLS-TP terminology.A BFD session is enabled when the CC or proactive CV/CC functionality is enabled on a configured Maintenance Entity (ME).An enabled BFD session can be in DOWN, INIT or UP stateWhen on a ME the CC or proactive CV/CC functionality is disabled, the BFD session transits in the ADMIN DOWN State and the BFD session ends.A new BFD session is initiated when the operator enables or re-enables the CC or CV/CC functionality on the same ME.
9Default Behavior both CC and CV mode Active Role is default, passive is optionalBFD timer values are set as followsTimer and detect multiplier re-negotiation is optional and disabled by defaultThe configured packet transmission is carried in “Desired Min TX Interval field”Bidirectional p2p settings:“Required Min RX Interval field” MUST be the same as “Desired Min TX Interval field”Unidirectional p2p and p2mp session MUST set the “Required Min RX Interval field“ to 0The session will NOT reach UP if expected timers values and detect multiplier are not the same
10BFD packets exchange (To be added to draft) Between MPLS-TP/MPLS nodes Will be adding scenarios describing:BFD packets exchange between a regular MPLS node , running ACH encapsulated BFD, and MPLS-TP node.BFD packets exchange between an MPLS-TP node and another MPLS-TP node.
11Next Steps Add more implementation details: Ask for workgroup adoption Behaviour of MEP receiving a BFD packet with AdminDown StateDiagnostic Code supportedAddress comments receivedAsk for workgroup adoption