Segment Routing. Jérôme DURAND Consulting Systems Engineer - FRNOG #21 20 septembre 2013

Transcription

1 Segment Routing Jérôme DURAND Consulting Systems Engineer - FRNOG #21 20 septembre Cisco and/or its affiliates. All rights reserved. 1

2 Simplicity Re- Use Traffic Engineering Scalability and FRR Programmability 2013 Cisco and/or its affiliates. All rights reserved. 2

3 Technology The application controls, the network delivers The state is no longer in the network but in the packet 2011 Cisco and/or its affiliates. All rights reserved. 5

4 FEC Z push A B C swap to swap to pop D Z A packet injected anywhere with top label will reach Z via IGP shortest path Packet to Z Packet to Z Packet to Z Packet to Z Packet to Z Nodes advertise a node segment simple IGP extension All remote nodes install node segment ids in data plane 2013 Cisco and/or its affiliates. All rights reserved. jerduran@cisco.com 6

5 A B C D Z Nodes advertises adjacency label per link N O P simple IGP extension Only advertising node installs adjacency segment in data plane Enables source routing along any explicit path (segment list) 2013 Cisco and/or its affiliates. All rights reserved. jerduran@cisco.com 8

6 Packet to Z Packet to Z 9003 Packet to Z A B C D Pop 9003 Z Source Routing M N O Packet to Z Any explicit path can be expressed: ABCOPZ P Packet to Z Packet to Z 2013 Cisco and/or its affiliates. All rights reserved. jerduran@cisco.com 9

7 2G from A to Z please Tunnel AZ onto {66, 68, } 66 FULL 68 Path ABCOPZ is ok. I account the BW. Then I steer the traffic on this path The network is simple, highly programmable and responsive to rapid changes 2013 Cisco and/or its affiliates. All rights reserved. jerduran@cisco.com 10

8 Properties 2011 Cisco and/or its affiliates. All rights reserved. 11

9 Implicit leverage of all MPLS excellent properties standardized and widely supported dataplane standardized and widely supported IP control plane (ISIS, OSPF, BGP) multi-service capability (VPN4, VPN6, 6PE, VPLS, evpn, PW ) Co-existence with MPLS as currently deployed Incremental deployment 2013 Cisco and/or its affiliates. All rights reserved. jerduran@cisco.com 12

10 Automation Fewer protocols to operate Fewer protocols interactions to troubleshoot Less state to maintain by routers 2013 Cisco and/or its affiliates. All rights reserved. 13

11 IP-based FRR is guaranted in any topology Backbone 2002, LFA FRR project at Cisco C1 C2 draft-bryant-ipfrr-tunnels-03.txt Directed LFA (DLFA) is guaranteed when metrics are symetric E1 E4 No extra computation (RLFA) E2 E Simple repair stack node segment to P node adjacency segment from P to Q Node segment to P node Default metric: Cisco and/or its affiliates. All rights reserved. jerduran@cisco.com 14

12 Each engineered application flow is mapped on a path millions of paths A path is expressed as an ordered list of segments The network maintains segments thousands of segments completely independent of application size/frequency Excellent scaling with complete application un-coupling the application state is no longer within the router but within the packet A path is mapped on a list of segments Millions of Applications flows The network only maintains segments No application state 2013 Cisco and/or its affiliates. All rights reserved. jerduran@cisco.com 15

13 Use Cases 2011 Cisco and/or its affiliates. All rights reserved. 16

14 A vpn cust B vpn cust Z Nodal Segment to D identified by global label vpn C D cust vpn cust Massive simplification most services just need shortest-path Automated 50msec FRR 2013 Cisco and/or its affiliates. All rights reserved. jerduran@cisco.com 17

15 A sends traffic with [] Classic ecmp a la IP A sends traffic with [11, ] Packet gets attracted in blue plane and then uses classic ecmp a la IP 2013 Cisco and/or its affiliates. All rights reserved. jerduran@cisco.com 18

16 From A to Z with SLA rqt (latency, bandwdith, disjointness) Use Segment Combo SR PCE Z A A Z SR Server performs Policy control Admission control (bandwidth) Path Computation and Segment-Combo Resolution Each application slice can change any of its path, any time 2013 Cisco and/or its affiliates. All rights reserved. jerduran@cisco.com 19

17 Conclusion 2011 Cisco and/or its affiliates. All rights reserved. 20

18 Simplicity Re- Use Traffic Engineering Scalability and FRR Programmability 2013 Cisco and/or its affiliates. All rights reserved. 21

19 Thank you.