SRv6 Net etwork Programming FD.io VPP and Linux Pablo Camarillo - - PowerPoint PPT Presentation

SRv6 Net etwork Programming FD.io VPP and Linux Pablo Camarillo - Software Engineer @ Cisco Systems Ahmed Abdelsalam – PhD student @ Gran Sasso Science Institute

Who are we? Ah Ahmed Ab Abdelsalam Pablo lo Ca Camarillo illo PhD student @ Gran Sasso Science Institute Software Engineer @ Cisco Systems ahmed.abdelsalam@gssi.it pcamaril@cisco.com (CC) FOSDEM 2018 (CC) FOSDEM 2018

1 SRv6 101 2 Deployment use-cases Agenda 3 SRv6 on FD.io VPP 4 SRv6 on Linux 5 SERA (CC) FOSDEM 2018 (CC) FOSDEM 2018

Segment Routing • Source Routing • the topological and service (NFV) path is encoded in packet header • Scalability • the network fabric does not hold any per-flow state for TE or NFV • Simplicity • automation: TILFA sub-50msec FRR • protocol elimination: LDP, RSVP-TE, NSH… • End-to-End • DC, Metro, WAN (CC) FOSDEM 2018

Two dataplane instantiations MPLS • leverage the mature MPLS HW with only SW upgrade • 1 segment = 1 label • a segment list = a label stack Segment Routing IPv6 • leverages RFC8200 provision for source routing extension header • 1 segment = 1 address • a segment list = an address list in the SRH (CC) FOSDEM 2018

IPv6 adoption is a reality Global IPv6 traffic gr grew ew 241% in 2016 Globally IPv6 traffic wi will grow w 16-fo 16 fold from 2016 to 2021 IPv6 wi will be 37% of total Internet traffic in 2021 % Web pages available over IPv6 Sources: 6lab.cisco.com – Web content Cisco VNI Global IP Traffic Forecast, 2016-2021 (CC) FOSDEM 2018

IPv6 provides reachability (CC) FOSDEM 2018

SRv6 – Segment Routing & IPv6 SR • Simplicity • Protocol elimination • SLA • FRR and TE SR for SR r anything else • Overlay IP IPv6 for reacha hability • NFV • SDN • SR is de-facto SDN architecture • 5G (CC) FOSDEM 2018

SRv6 for underlay SR Simplification through protocol reduction SR SRv6 for RS RSVP for FRR/T r Un Underl FRR/TE rlay Horrendous states scaling in k*N^2 SLA through automated FRR and TE De-facto SDN architecture IP IPv6 for reacha hability (CC) FOSDEM 2018

SRv6 for underlay and overlay SR NSH for NFV Additional Protocol and State UDP+VxLAN Overlay Additional Protocol just for tenant ID SRv6 for SR r Un Underl rlay Simplification, FRR, TE, SDN IP IPv6 for reacha hability Multiplicity of protocols and states hinder network economics (CC) FOSDEM 2018

SR for anything: Ne Netwo work as a Computer (CC) FOSDEM 2018

Network instruction Locator Function • 128-bit SRv6 SID • Locator: routed to the node performing the function • Function: any possible function either local to NPU or app in VM/Container • Flexible bit-length selection (CC) FOSDEM 2018

Network instruction Locator Function Args* • 128-bit SRv6 SID • Locator: routed to the node performing the function • Function: any possible function either local to NPU or app in VM/Container • Ar Argumen ents: o optional al ar argumen ent b bits t to b be u e used ed o only b by t that at S SID • Flexible bit-length selection (CC) FOSDEM 2018

Network Program Next Segment Locator 1 Function 1 Locator 2 Function 2 Locator 3 Function 3 Locator 2 Function 2 Locator 1 Function 1 Locator 3 Function 3 (CC) FOSDEM 2018

Network Program Locator 1 Function 1 Next Segment Locator 2 Function 2 Locator 3 Function 3 Locator 2 Function 2 Locator 1 Function 1 Locator 3 Function 3 (CC) FOSDEM 2018

Network Program Locator 1 Function 1 Locator 2 Function 2 Next Segment Locator 3 Function 3 Locator 2 Function 2 Locator 1 Function 1 Locator 3 Function 3 (CC) FOSDEM 2018

Network Program in the Packet Header IPv6 header Sou Source Address Locator 1 Lo Func Fu nction n 1 Segment Active Segment Lo Locator 1 Fu Func nction n 1 Routing Lo Locator 2 Func Fu nction n 2 Header Locator 3 Lo Fu Func nction n 3 IPv6 payload TC TCP, UDP DP, QUIC (CC) FOSDEM 2018

Argument shared between functions TAG TA Se Segments ts Left Lo Locator 1 Fu Func nction n 1 Locator 2 Lo Fu Func nction n 2 Lo Locator 3 Fu Func nction n 3 “Global” Argument Metadata TLV (CC) FOSDEM 2018

Group-Based Policy TAG TA Se Segments ts Left Lo Locator 1 Fu Func nction n 1 Locator 2 Lo Fu Func nction n 2 Lo Locator 3 Fu Func nction n 3 Metadata TLV (CC) FOSDEM 2018

SRv6 Header SR TAG TA Se Segments ts Left Lo Locator 1 Fu Func nction n 1 Lo Locator 2 Fu Func nction n 2 Lo Locator 3 Fu Func nction n 3 Metadata TLV (CC) FOSDEM 2018

SRv6 LocalSIDs (CC) FOSDEM 2018

Endpoint function >VPP: show sr localsid >VPP: show sr localsid LocalSID Behavior LocalSID Behavior A6::1 End A4::1 End Total SR LocalSIDs: 1 Total SR LocalSIDs: 1 SR: � A4 SR A4::1, A6 A6::1, A8 A8:: � A1 A1 A3 A3 A6 A6 A1:: A3:: A6:: A5 A5 A8 A8 A5:: A8:: 50 50 A2 A2 A4 A4 A7 A7 A2:: A4:: A7:: Default metric 10 • For simplicity function 1 denotes the most basic function • Shortest-path to the Node (CC) FOSDEM 2018

Endpoint then xconnect to neighbor function >VPP: show sr localsid >VPP: show sr localsid LocalSID Behavior LocalSID Behavior A6::1 End A4::C5 End.X {TenGE0/1/0 A5::} Total SR LocalSIDs: 1 Total SR LocalSIDs: 1 SR: � A4 SR A4::C5, A6 A6::1, A8 A8:: � A1 A1 A3 A3 A6 A6 A1:: A3:: A6:: A5 A5 A8 A8 A5:: A8:: 50 50 A2 A2 A4 A4 A7 A7 A2:: A4:: A7:: Default metric 10 • For simplicity Ak::Cj denotes: Shortest-path to the Node K and then x-connect (function C) to the neighbor J • (CC) FOSDEM 2018

Deployment use-cases (CC) FOSDEM 2018

A2::C4 A2 C4 TILFA 2 4 100 A5 A5::0 1 • 50msec Protection upon local link, node or SRLG failure 6 5 • Simple to operate and understand A5 A5::0 A5::0 A5 • automatically computed by the router’s IGP process <50mec FRR <50m • 100% coverage across any topology • predictable (backup = postconvergence) A5 A5::/64 Pr Pri → vi via 5 • Optimum backup path FR FRR → i insert A A2::C4 • leverages the post-convergence path, planned to carry the traffic • avoid any intermediate flap via alternate path • Incremental deployment • Distributed and Automated Intelligence (CC) FOSDEM 2018

Centralized TE Low-La Low Latency to 7 7 for a fo application … … Input Acquisition • BGP-LS • Telemetry 12 12 <A1::1, 10 10 A2::C4, Policy Instantiation 2 4 Low La Low Lat, L Low B BW 50 50 A4::C7> 1 • PCEP 7 13 13 • BGP-TE 6 5 3 • Netconf / Yang 11 11 Algorithm 14 14 • SR native Default ISIS cost metric: 10 DC (BGP-SR) PEER WAN (IGP-SR) (CC) FOSDEM 2018

T/ T/64 Overlay 3 IPv6 Hdr SA = T::1, DA = V: V::2 Payload • Automated Green Overlay 1 V/64 • No tunnel to configure via A2::C4 • Simple IPv6 Hdr SA = A1 A1::0 , DA = A2 A2::C4 • Protocol elimination IPv6 Hdr SA = T::1, DA = V: V::2 Payload • Efficient • SRv6 for everything 2 IPv6 Hdr SA = T::1, DA = V: V::2 Payload 4 V/64 V/ (CC) FOSDEM 2018

T/64 T/ Overlay with Underlay Control 3 SA = T::1, DA = V: V::2 IPv6 Hdr Payload • SRv6 does not only eliminate Green Overlay 1 unneeded overlay protocols V/64 IPv6 Hdr SA = A1 A1::0 , DA = A3 A3::1 via A2::C4 SR Hdr < A3 A3::1 , A2::C4 > • SRv6 solves problems that with Latency IPv6 Hdr SA = T::1, DA = V: V::2 these protocols cannot solve Payload 3 IPv6 Hdr SA = A1 A1::0 , DA = A2 A2::C4 SR Hdr < A3::1, A2 A2::C4 > IPv6 Hdr SA = T::1, DA = V: V::2 Payload 2 IPv6 Hdr SA = T::1, DA = V: V::2 Payload 4 V/64 V/ (CC) FOSDEM 2018