Presentation on theme: "Towards PAR for Segment Protection Switching"— Presentation transcript:
1 Towards PAR for Segment Protection Switching M Vinod KumarAbhay Karandikar
2 Agenda Refresh Motivation Gaps in Present Standard Terminology for Segment Protection- agreed so farSummary of Segment Protection RequirementsSummary of Segment Protection Solutions discussed so far in the groupPros and Cons of various solutionsNeed for a PAR
3 Prior ArtsEilat (May Interim) - Abhay presents SPS as means to solve P2MP protectionay-Abhay-Protection-Switching-for-P2MP-0508.pptDenver (July Plenary) – Jointly by Abhay, Bob and Johnnew-sultan-fast-reroute-te-0708-v02.pdfSeoul (Sept Interim) - Bob presents interpretations and observations, Dave presents issues to address and Vinod presents case for SPSnew-sultan-segment-protection-scaling-0908-v01.ppsnew-martin-PBB-TE-segment-prot-0908-v01.pdfnew-Protection-Vinod-Case-for-Segment-Protection-0908-v1.ppsDallas (Nov Plenary) -Vinod uploads document on case for SPS and No new work prez due to Lack of timenew-Vinod-SegmentProtectionSwitching-1108-v01.docnew-martin-PBB-TE-segment-prot-1108-v00.pdfnew-sultan-segment-protection-requirements-1108-v02.pdfNew Orleans (Jan Interim) – Dave presents client-server method, Wei presents 3-tupple translation, Bob presents segment protection for infrastructure, and Vinod presents four distinct methodsnew-martin-PBB-TE-segment-prot-0109-v00.pdfnew-weiyh-segment-protection-0109-v00.pdfnew-sultan-segment-protection-technical-proposal-0109-v01.pdfnew-vinod-SPS-modeling-0109-v1.ppt
4 Motivation Reference: Carrier Requirements: new-Protection-Vinod-Case-for-Segment-Protection-0908-v1.ppsCarrier Requirements:Infrastructure failure- major cause of outageService providers have the knowledge that certain links are more prone to failureUpcoming areas/floods/road constructionProtection models must include N:1
5 Gaps in Present Standard PBB-TE has addressed end-to-end protection of P2P TESI within a single domain.Service providers need efficient mechanism to protect vulnerable links of the topologyN:1 is not addressed in PBB-TE.
6 Definitions of Segment A Segment is a single link, or a sequence of links and bridges, providing connectivity between two bridges. The segment is bounded at each end by a Provider Network Port (PNP). A bridge lying within the segment is a BCB. A segment endpoint bridge is a BCB or an IB-BEB.A Primary segment is a segment along whose path one or more TESIs have been coincidently provisionedA Backup segment is a segment having the same endpoint bridges as the primary segment but whose path is otherwise disjoint from the primary segment.An Infrastructure Segment is Sequence of links and bridges that protects atleast one TESI coincident with itA Data Path Segment is portion of a TESI bounded by a PNP at each endMultiple Data Path segments can be associated with an infrastructure segmentInfrastructure Protection - Preserve connectivity of all TESIs transiting an active infrastructure segment on the failure of one or more links or bridges associated with that segment.Data Path Protection - Preserve connectivity of a TESI in the presence of a TESI data path failure occurring within the active TESI segment due to link failure, node failure, FDB corruption, etc.M:1 Protection – Support multiple backup segments (M≥1) to which traffic can be switched in the event of the failure of the primary segment. The backup segment having the highest provisioned priority value among operational backup segments is selected to be the active segment. Should support Load Balancing. M = 3 atleast.
7 Types of Segment Protection Schemes Infrastructure Segment ProtectionData Path Segment ProtectionThere is an agreement on the requirements for Infrastructure Segment Protection
8 Infrastructure Segment Protection Requirements new-sultan-segment-protection-requirements-0109-v01.pdfnew-irene-Segment-Protection-Requirements-0309-v01.pptMaintain the same or better quality of transport as offered by PBB-TEEnd-to-end integrity must be honoredSolution must be operationally simple and should not require large number of provisioning actionSolution shall not switch traffic when there is no fault unless required by management commandsShall have minimal impact on bridge architectureShall support N:1 protection group with load sharing supportAddress the relatively high failure rate of particular links or bridges within a network.Address the likelihood of concurrent failures occurring in different segments of a network.Allow maintenance activities to be performed independently in different segments of the network.Provide an efficient means of protecting portions of a PtMP TESI.Blind Switching as per Tejas are of two types:Type 1: This arises due to not checking the switching of TESI over the backup infrastructure segmentType 2: This concerns with the action of monitoring a segment with different identifiers, different from the actual TESI_ID, and assuming that the TESI has failed if Infrastructure segment CCM has failed.Both type of blind switching are to be avoided in a transport network. In a data network Type 1 is enough, but in packet transport network!
9 Segment Protection Solutions Segment Protection Solutions can be broadly classified in three types:Hierarchical (Client server by Dave, Triple Q by Vinod Tejas)Cascaded (Tuple switch by Wei ZTE, BB-BEB model by Vinod)Port redirection by Bob
10 Hierarchical Segment Protection This is also known as Client-Server model (Dave) or Triple MAC (Vinod)Upgrade the BCBs at the edges of the segment to IB-BEBs and provide a PBB hierarchal (802.1ah ) S-tagged interface (802.1ah 25.4)Each segment is now a new (server layer ) TESI in a regular PBB-TE 1:1 TESI PG, with the corresponding TESI CCM integrity coverage
11 Cascaded Segment Protection Also known as 3-tupple translation (Wei Yuehua) or Enhanced BB-BEB (Vinod)
12 Overlay Segment Protection Also known as port-redirect (Bob Sultan)Only addresses Infrastructure Segment Protection SwitchingSpecial logic needed at AIB and PIB to correlate the faults and port-redirect or switch the TESI without forwarding ambiguity
13 HW complexity increase Minimum HW complexity Same HW logic Yes FeaturesHierarchical PBB-TE3-Tupple TranslationPort-redirectData Frame sizeIncreaseSameStandards ImpactNoneMinorHardware LogicSame as .1ahSame as .1adPlacement at the BEBHW complexity increaseMinimum HW complexitySame HW logicControl Plane Logic (AIB)YesRetracingProtection ScopeGroup of TESIsTESIGroup of TESIData Path IntegrityNoBlind SwitchScalabilityCCM complexityPer SegmentPer TESIper AIB or PIBReinforcing ProposalsE-NNI v2 in MEF and IEEEAlternate competing StandardsG.8032 v2Support for InfrastructureForwarding Ambiguity
15 What do we get?Protection segments are pre-provisioned to allow sub-50ms protection switchingThe segments forming protection group are constantly monitoredOptimal network resource utilizationBy protecting portion of e2e TESIBy supporting load sharing with N:1By supporting minimal provisioning for protection
16 Value PropositionSegment Protection has same economic feasibility as that of Backbone Edge BridgesThe protection mechanism is applicable to any topologyImproves network utilization by not performing e2e protection whenever possibleReduces provisioning complexity of e2e protection mechanism by protecting portion of e2e transportEnables protection of critical portion of a packet transportEnables efficient protection of branches of P2MP
17 OAM requirements OAM shall reuse PBB-TE OAM components No need to use unreliable control plane
18 What would IEEE specify Amendment to QayAmend .1ag
19 TitleIEEE standard for Local and Metropolitan Area Networks --- Virtual Bridged Local Area Networks --- Amendment ?? --- Transport Segment Protection Switching
20 Scope: What project isThe scope of this project is to define feature extension of 802.1Q (2005) supporting protection of critical portion of the provisioned or traffic engineered services by offering at-least the same guarantee as offered originally by the traffic engineered services with minimal impact on existing standards
21 Scope: What Project is not The project will only provide features necessary to support external management plane command or control plane.The selection of protection segment and bandwidth management either through management commands or by control plane is outside the scope of this project
22 Scope: Required Features The features specified in this project enhance, support and rely on the PBB (IEEE 802.1ah), PBB-TE (IEEE 802.1Qay), and CFM (IEEE-802.1ag) standards. In doing so, it shall:Maintain the same or better quality of transport as offered by PBB-TEEnd-to-end integrity must be honoredSolution must be operationally simple and should not require large number of provisioning actionSolution shall not switch traffic when there is no fault unless required by management commandsShall have minimal impact on bridge architectureShall support N:1 protection group with load sharing supportAddress the relatively high failure rate of particular links or bridges within a network.Address the likelihood of concurrent failures occurring in different segments of a network.Allow maintenance activities to be performed independently in different segments of the network.Provide an efficient means of protecting portions of a PtMP TESI.
23 PurposeAn important objective of provisioned packet transport is to efficiently protection switch the trafficUse less network resourcesSub-50 ms resiliencyBuild on existing standard building blocksProvide aggregate protection of all TESIThis project will amend the .1Q standard
24 Need for ProjectCurrently there is no mechanism to manage portion of a (provisioned) packet transport that is liable to fail more often than other portion of the packet transportThe project will address OAMP and protection switching of critical portion of the end-to-end packet transport and support N:1 load sharing
25 StakeholdersDevelopers and users of networking for Provider network environments including networking IC developers, switch and NIC vendors, and users.