FlexE - Channel Control Work in the IETF Loa Andersson (loa@pi.nu) Mach Chen (mach.chen@huawei.com) Jie Dong (jie.dong@huawei.com) Zongpeng Du (duzongpeng@huawei.com)
Multi-hop Flex Ethernet Channel The definition of the MAC layer and PHY layer for FlexE has been defined by OIF in the FlexE 1.0. The main features are: multiple PHYs bonding, forming a virtual link with large bandwidth, and chopped into slots Slot-based encoding on the PHYs, each MAC client has its particular slots (5Gbits/s per slot) The most straightforward scenarios are: Directly connected FlexE routers Flexe routers connected over an OTN network Another scenario is multi-hop FlexE channel, which will be the main topic of this slide; it means that FlexE can also be used in a pure Router network In draft-izh-ccamp-flexe-fwk-00, this scenario is called “the back-to-back FlexE use case” Interfaces are FlexE based A FlexE client have specific slots on the interface, i.e., ensured bandwidth on the interface Forwarding in the Routers can be Ethernet/MPLS/IP based draft-izh-ccamp-flexe-fwk-00
Benefits of Multi-hop FlexE Channel “Hard pipes” – paths with bandwidth the can not be infringed upon nor exceeded. MPLS hard pipes were specified in RFC 7625 “Architecture of an IP/MPLS Network with Hardened Pipes” “IP Hard pipes” is now under study – draft will be posted after the cut-off is lifted In IP Networks we sometimes need to provide bandwidth guaranteed service For (G)MPLS networks this is done by the use of MPLS-TE FlexE is a potential solution for part of the IP “hard pipe” technology FlexE provides guaranteed bandwidth, which is beneficial for latency of the service. FlexE can be used to establish a multi-hop FlexE Channel, and to ensure the QoS E2E FlexE offers a very stable hardware guarantee to the QoS For some set of services FlexE can be used to improve QoS in IP networks
Potential impact from FlexE in work in IETF The work will start in CCAMP (draft-izh-ccamp-flexe-fwk) This draft is a convergence of ideas from several other individual draft It gives a high level description of what FlexE is The draft outlines Use cases, e.g. ways to inter-connect FlexE capable equipment Requirements, e.g. FlexE signaling Architecture and Framework, Solutions, extensions to IETF protocols Applicability The draft also introduces FlexE specific terminology
Potential impact from FlexE on work in IETF CCAMP Use Cases, Requirements, Framework, Architecture, extensions to RSVP-TE to establish signaled FlexE channels MPLS Coordination with CCAMP when the MPLS data plane is used RTGWG Potentially work on IP (unicast and multicast) Hard Pipes PCE Work in coordination with CCAMP on FlexE path computation DETNET FlexE impact on deterministic networking OSPF and ISIS Solutions for FlexE Traffic Engineering and capability announcements TEAS Coordination with CCAMP/MPLS on traffic engineering architecture and solutions
Thanks
Appendix: Flex-Ethernet Overview An example to introduce FlexE concept: The FlexE interface between Node 1 and Node 2 includes 4 physical links (4*100G), called FlexE Group. They are bonded together to form a virtual link with large bandwidth to serve FlexE Clients In the Figure, there are two FlexE Clients. Their MAC frames are 64B/66B encoded, and the 64B/66B bitstream will be scheduled by the FlexE shim, and distributed sequentially into the calendar and sub-calendar. For a FlexE group composed of 4 bonded 100G PHYs, logically, the calendar contains 80 slots (5Gbits/s per slot) Node1 and Node2 share the same calendar, which contains the information about which FlexE client a slot belongs to. The calendar is negotiated or configured before the data transferring, and is used for mapping the FlexE clients into the FlexE group and demapping the FlexE clients from the FlexE group MAC FlexE Shim PHY Node 1 Node 2 FlexE Group: Bonded Ethernet PHYs Forming a virtual link FlexE Clients: Virtual MAC interface, whose rate is not limited to the existing Ethernet PHY rates defined in IEEE Illustration of FlexE Calendar Distribution Illustration of Data Flow for FlexE Mux Cited from OIF-FLEXE-01.0 Cited from OIF-FLEXE-01.0