Extending OTN Standards to Support Ethernet Services

1. Extending OTN Standards to Support Ethernet Services Maarten Vissers

2. Introduction • Recently, Optical Transport Network (OTN) capabilities have been extended to make it flexible and feature rich • OTN is now a multi-service transport network supporting multitude of services: • any type of CBR service – including 1G, 10G, 40G and 100G (a)synchronous Ethernet streams • ATM, Ethernet, MPLS, IP packet clients and Ethernet Private Line (EPL) services • Carriers demand extension of OTN standards to support Ethernet Private Tree (EPT), LAN (EPLAN) and Ethernet Virtual Private Line (EVPL), Tree (EVPT), LAN (EVPLAN) services • With the above services the OTN is able to interconnect two or more routers, Ethernet switches, PBNs, PBBNs, PBB-TENs, etc. (see )

3. Introduction ITU-T Q.9/15 and Q.11/15 received proposals for architecture and frame formats to support EPT, EPLAN, EVPL, EVPT and EVPLAN services in OTN The proposals are based on the addition of a well defined ETH layer on top of the OTN Lower Order ODU layer This ETH layer is referred to as Ethernet Virtual Channel (ETH VC) layer Q.9/15 decided to liaise these proposals to 802.1 for review and feedback prior to progressing the work in Q9/15 NOTE – The definition of the ETH layer is based on IEEE Ethernet standards and extensively used in ITU recommendations G.8010/G.8021/G.8031/G.8051. The ETH MEP, MIP, Connection and Protection functions and processes defined in these recommendations are to be used without modifications. To be added is an ODU-to-ETH VC adaptation function.

4. Requirements • The proposals were used as a starting point for developing a set of requirements based on: • Service types to support • Service encapsulation types to support • OTN architecture extension • ETH VC encapsulation, identification and reserved address transparency • ETH VC Management • Interoperability with 802.1Q edge nodes and networks • The above items are addressed in subsequent slides

5. Service types As a general principle, the OTN should accept customer Ethernet service signals from any type of 802.3/802.1Q UNI or V-UNI Untagged LANs, Priority-C-Tagged LANs, C-Tagged LANs, Priority-S-Tagged LANs, S-Tagged LANs, S+C-Tagged LANs, I-Tagged LANs and S+I-Tagged LANs. support untagged, priority tagged, single tagged and double tagged ETH Characteristic Information (ETH_CI) service types support transparent, port-based, individual and bundled ETH_CI type services support the 802.1Q defined ETH_CI service types See for an illustration of those service types

6. Service encapsulation • The OTN should be able to accept the customer’s ETH_CI and • transport this ETH_CI without further encapsulation (peering mode) • transparent transport of the top N MEG OAM levels (e.g. MELs 7,6,5), the lower 8-N MEG OAM levels are used by the OTN • encapsulate this ETH_CI to preserve its VLAN or Service Identifier (VID/SID), Priority Code Point (PCP) and Drop Eligible Indicator (DEI) values present on the (V-)UNI (client/server mode) • transparently transfer the information in the C-, S- or I-Tag associated with the customer’s ETH_CI • encapsulate this ETH_CI within the payload of a new MAC frame • operator controlled option, beneficial in E-Tree/E-LAN service cases • limits the number of MAC Addresses to learn in a rmp or mp2mp ETH VC connection in the OTN • customer’s ETH_CI frame – with or without its Tag on the (V-)UNI – will be prepended with a TYPE, SA and DA field • See for an illustration of those service encapsulations

7. OTN architectureextension • The OTN should • support all service types by a single layer network • Restrict visibility of the different UNI interface presentations to the UNI-N ports • support the defined services by means of an additional Virtual Channel (VC) layer (see ) • transport the VC signals over LO ODUk connections which interconnect VC layer switching functions • The VC layer in the OTN should • support p2p, p2mp, rmp and mp2mp VC connections to support the EVPL, E(V)PT and E(V)PLAN services • be an Ethernet (ETH) based VC layer network • deploy Y.1731 Ethernet OAM to monitor the VC connection status and performance • deploy G.8031 Ethernet linear protection switching

8. VC encapsulation • The OTN should encapsulate each ETH VC frame in the same manner, independent of the • customer service supported by the ETH VC • number of ETH VC signals (1 or n) carried in the LO ODUk connection • The encapsulation header should include fields to identify the • ETH VC to which the frame belongs • if a single ETH VC signal is carried in the LO ODUk connection (private service case) the identifier field may be set to a default null value • priority and drop eligibility of the frame • See for an illustration of ETH VC frame encapsulation

9. VC identification • The OTN should • support link local ETH VC connection identifiers • Default approach to support scalability of connections in a transport network • Allows for ETH VC ID interchange at link ends under control of ETH VC connection manager • identify frames of a (p2p, p2mp, rmp and mp2mp) ETH VC connection by means of a single identifier value per link • For the case of a “multi-root rooted-multipoint” ETH VC the use of a single identifier value per link might not be possible. Instead the use of two identifier values may be required. This is under study.

10. ETH VC managementand survivability • The OTN should • manage (set up, modify, tear down, configure) the ETH VC connections and their MEP and MIP functions under control of NMS and/or ASON/GMPLS • increase survivability of the ETH VC connections by means of G.8031 ETH Sub-Network Connection (SNC) protection switching and/or GMPLS based ETH VC restoration • dual homing and/or dual node interconnect (DH/DNI) methods under development in Q.9/15 should be deployed to survive multiple faults

11. ETH VC Reserved Addresses transparency • The ETH VC switching functionality in the OTN may be represented by means of an “ETH VC Component” • The “ETH VC Component” includes a MAC Relay, OTN Network Ports and optionally PB/PBB Facing Port(s) • The “ETH VC Component”Reserved Address set should be minimized to provide maximum transparency for clients • This minimal set is to be defined ETH VC Network Port ETH VC Component ETH VCMAC Relay PB, PBB Facing Port OTN Network Port OTN Network Port Ethernet NNI ODU_CI ODU_CI

12. Universal Ethernet(V-)UNI-N port • It is an objective to specify a universal Ethernet UNI-N/V-UNI-N port which supports the set of EPT, EPLAN, EVPL, EVPT and EVPLAN services • This (V-)UNI-N port includes a (V-)UNI Facing Port, an ETH VC Network Port and a MAC Relay function • This port should be configurable to support any service type (V-)UNI-N Port MAC Relay (V-)UNI Facing Port ETH VC Network Port ETH VCMAC Relay UNI or V-UNI

13. Interoperability with802.1Q edge nodes and networks • EVPL, EVPT and EVPLAN services supported by the OTN may have one or more of their UNI-N ports located outside the OTN • E.g. located in PEB, I-BEB, B-BEB, IB-BEB devices • The OTN should connect via an S- or I-Tagged LAN Ethernet NNI to those devices directly, or via an intermediate PB, PBB or PBB-TE network (see ) • The ETH VC signal should in those cases be encapsulated with an S-Tag or I-Tag

14. ETH VC over PB, PBB, PBB-TE networks • Question: under which conditions can an ETH VC signal be transported through a PBN, PBBN and PBB-TEN? • In the OTN an ETH VC frame is combined with an ETH VC Tag • If an ETH VC frame is combined with an S-Tag it looks like a S-VLAN and could then be transported through a PBN via a CNP on a PB or PEB node • If an ETH VC frame is combined with an S-Tag it looks like a S-VLAN and could then be transported through a PBB-TEN via a CNP on an IB-BEB • If an ETH VC frame is combined with an I-Tag it looks like a BSI and could then be transported through a PBBN via a CBP on a B-BEB or IB-BEB

15. ETH VC termination inPEB, I-BEB, B-BEB, IB-BEB, T-BEB • Question: under which conditions can an ETH VC signal be terminated in a PEB, I-BEB, IB-BEB or T-BEB? • ETH VC frames should be S- or I-Tagged as required by those nodes • ETH VC’s client signal should be a supported client signal of the node (see for an overview)

16. Summary • The addition of one ETH (VC) layer on top of the OTN’s LO ODU layer together with ETH switching functions in a subset of OTN cross connects enables the OTN to support EPT, EPLAN, EVPL, EVPT and EVPLAN services for any of the possible service types. • A ETH VC Tag is required to mark each ETH VC frame within a LO ODU signal. It seems that this Tag can’t be one of the 802.1Q defined Tags. • The Ethernet services may have a subset of their endpoints located outside the OTN, e.g. within 802.1Q defined nodes. Interoperability between the service layer in the OTN and the service layer in a PB, PBB and PBB-TE network and/or edge node is anticipated. Under which preconditions would this be possible?

17. Backup

18. ETH_CI and ETH_AI ETH Adapted Information (AI) MAC_SDU Encapsulated client OAM: APS, MCC, CSF SA DA Priority Drop Eligible ETH Characteristic Information (CI) MAC_SDU Encapsulated client OAM: APS, CSF, MCC OAM: CCM, AIS, LCK, LBx, LTx, TST, LMx, DMx SA DA Priority Drop Eligible

19. Ethernet servicesover OTN examples ETH VCC 3 ETH VCC 1 ETH VCC 5 ETH VCC 2 ETH VCC 7 ETH VCC 4 ETH VCC 6 .1QN .1QN PBBN .1Q .1Q C-Tagged LAN LAN B-BEB C-Tagged LAN PBBN OTN I-Tagged LAN I-Tagged LAN B-BEB PBN PBN PB S-Tagged LAN S-Tagged LAN PB S-Tagged LAN PBBN PB PBN B-BEB I-Tagged LAN C-Tagged LAN LAN .1Q .1QN

20. Service typeson Ethernet UNIs/V-UNIs UNI Link UnTagged or Priority-Tagged ETH_CI UNI Link UNI Link C-Tagged or S-Tagged or I-Tagged or B-Tagged ETH_CI ETH_CI service UNI Link UNI Link UNI Link S- + C-Tagged or S- + I-Tagged ETH_CI ETH_CI service ETH_CI service UNI Link (V-)UNILink UNI Link UNI Link ETH_CI service ETH_CI service ETH_CI service ETY_CI or ETH_CI service • Transparent service • Port based service • C-Tagged service • S-Tagged service • I-Tagged service • C-Tagged service • I-Tagged service Bit/CodeWord stream service EPL Type 2EPL Type 2/TT EPL Type 1, EVPL Type 2EPT, EVPT Type 2 EPLAN, EVPLAN Type 2 EVPL Type 1/3EVPT Type 1/3EVPLAN Type 1/3 EVPL Type 1/3EVPT Type 1/3EVPLAN Type 1/3

21. Service encapsulationin Ethernet based VC layer OAM OAM TYPE 89-02 TYPE 89-02 DA/SA DA/SA MSDU MSDU MSDU MSDU MSDU Encapsulated client information MSDU C-Tag I-Tag C-Tag S-Tag S-Tag I-Tag S-Tag Sufficient encapsulation for P2P E-LINE and P2MP E-Tree services supported by p2p and p2mp ETH VC connections DA/SA DA/SA DA/SA DA/SA DA/SA DA/SA Y.1731 G.8021 G.8031 G.8051 Ethernet VC layer MSDU MSDU MSDU MSDU MSDU MSDU Encapsulated client information C-Tag I-Tag C-Tag S-Tag S-Tag I-Tag S-Tag DA/SA DA/SA DA/SA DA/SA DA/SA DA/SA Type 89-10 Type 89-10 Type 89-10 Type 89-10 Type 89-10 Type 89-10 Best encapsulation for RMP E-Tree and MP2MP E-LAN services supported by rmp and mp2mp ETH VC connections DA/SA DA/SA DA/SA DA/SA DA/SA DA/SA Y.1731 G.8021 G.8031 G.8051 Ethernet VC layer

22. OTN architecturewith additional ETH VC layer Additional VC layer Ethernet-UNI Ethernet-UNI UserNetwork UserNetwork Optical Transport Network Customer Ethernet layer Eth Eth 1:1 or n:1 1:1 or n:1 Ethernet Virtual Channel layer (ETH VC) VC Type I Eth VC Type II Eth EVPL EVPTEVPLAN EPTEPLAN 1:1 n:1 UNI specific EVC server layers UNI specific EVC server layers LO ODU layer n:1 HO ODU layer OTU layer OTU layer OCh layer OCh layer OTN transmission media layers OMSn+OTSn or OPSn or OPSMnk

23. ETH VC encapsulationin OTN LO ODU layer ETH VC frames are Tagged and then mapped into a GFP-F frame MAC FCS is appended to the GFP-F frame GFP-F frame is mapped into ODU payload area GFP Idle frames are inserted in absence of ETH VC frames See next slide for illustrations OAM TYPE 89-02 DA/SA Ethernet VC layer ETH VC Tag + MAC FCS ETH VC encapsulation headers/trailers GFP-F Header LO-ODU A/GMP OTN HO-ODU Wavelength Transmission Media

24. ETH VC encapsulation Eth VC Tag can not be a C-Tag, S-Tag or I-Tag Eth VC Tag should be a new Tag MAC FCS MAC FCS MAC FCS MAC FCS MAC FCS MSDU MSDU MAC FCS MSDU MSDU MSDU MAC FCS MSDU Encapsulated ETH VC information OAM C-Tag I-Tag C-Tag S-Tag S-Tag I-Tag S-Tag TYPE 89-02 One tag for all Eth VC Tag Eth VC Tag Eth VC Tag Eth VC Tag Eth VC Tag Eth VC Tag Eth VC Tag DA/SA DA/SA DA/SA DA/SA DA/SA DA/SA DA/SA GFP Header GFP Header GFP Header GFP Header GFP Header GFP Header GFP Header MAC FCS MAC FCS MAC FCS MAC FCS MAC FCS MSDU MSDU MAC FCS MSDU MSDU MSDU MSDU C-Tag I-Tag Encapsulated ETH VC information MAC FCS C-Tag S-Tag S-Tag I-Tag S-Tag OAM DA/SA DA/SA DA/SA DA/SA DA/SA DA/SA Type 89-10 Type 89-10 Type 89-10 Type 89-10 Type 89-10 Type 89-10 TYPE 89-02 One tag for all Eth VC Tag Eth VC Tag Eth VC Tag Eth VC Tag Eth VC Tag Eth VC Tag Eth VC Tag DA/SA DA/SA DA/SA DA/SA DA/SA DA/SA DA/SA GFP Header GFP Header GFP Header GFP Header GFP Header GFP Header GFP Header

25. PTN NT Eth UNI PTN NT A ETM-n with I-Tagged ETH VCs N IB-BEB TE M Universal Eth UNI Universal Eth UNI PBB- TEN IB-BEB TE Eth UNI ETM-n with S-Tagged ETH VCs PBBN B-BEB B I-BEB BCB TE B-BEB B-BEB I-Tagged ETH VCs IB-BEB TE Eth UNI S-Tagged ETH VCs C T-BEB B-BEB BCB BCB Eth UNI Eth UNI I-Tagged ETH VCs D PEB S-Tagged ETH VCs E PBN PB PB S-Tagged ETH VCs PB ETM-n with S-Tagged ETH VCs PB PTN NT F I-Tagged ETH VCs Universal Eth UNI G I-BEB ETM-n with ETH VCs S-Tagged ETH VCs Eth UNI H PEB PTN NT I PB = Eth UNI Universal Eth UNI L Universal Eth UNI OTN Eth VC Tag EOTN EOTN EOTN XC EOTN OTN Universal Eth UNI OTN EOTN EOTN XC K EOTN OTN OTM-0 with ETH VCs EOTN EOTN J EOTN NT EOTN EOTN Universal Eth UNI

26. Service typessupported by node/port type