Segment Routing: Technology Update and Advanced Use-Cases
Steve Braaten, Solutions Architect
BRKRST-3122
• Segment Routing Executive Summary
• Reminders
• Incremental Deployment Use-Cases
• Inter-Domain Policy at Scale
• Topology Independent LFA (TI-LFA)
• Microloop Avoidance
• Conclusion
Agenda
Segment RoutingExecutive Summary
© 2016 Cisco and/or its affiliates. All rights reserved. Cisco Public
Segment Routing
• Source Routing
• the source chooses a path and encodes it in the packet header as an ordered list of segments
• the rest of the network executes the encoded instructions
• Segment: an identifier for any type of instruction
• forwarding or service
• Forwarding Plane:
• MPLS: an ordered list of segments is represented as a stack of labels
• IPv6: an ordered list of segments is encoded in a routing extension header
• Multi-Vendor solution
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Deployed !
• First deployments in 2015 – just 15 months after FCS !!!
• Strong start in 2016 with many new deployments
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IETF
• Strong commitment for standardization andmulti-vendor support
• SPRING Working-Group (started Nov 2013)
• All key documents are WG-status
• Over 25 drafts maintained by SR team
• Over 50% are WG status
• Over 75% have a Cisco implementation
• Several interop reports are available
• First RFC document - RFC 7855 (May 2016)
www.segment-routing.nettools.ietf.org/wg/spring/
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Foundation for modern IP/MPLS networking
• Simplicity
• Set of few, well-chosen building blocks
• Solution to unsolved problems
• End-to-end policy, local and/or centralized PCE, 50msec protection, microloop avoidance, and more…
• Scale
• Granular traffic engineering with minimal network state
• Seamless Deployment
• SR/LDP interworking, SR/RSVP-TE interworking, ship-in-the-night co-existence
• Decoupled data and control planes
• Low-cost
1
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Session Assumptions
• Thorough understanding of SR tutorial
• http://www.segment-routing.net/home/tutorial
• You should know
• SRGB
• IGP Prefix and Adj SID’s
• Anycast SID
• SR/LDP interworking
• BGP Prefix SID and the MSDC use-case
• Use-Cases in this presentation described for SR/MPLS
• Same concept applies to SRv6 (native IPv6 SR extension header, no MPLS)
BRKRST-3122 9
Reminders
© 2016 Cisco and/or its affiliates. All rights reserved. Cisco Public
Prefix segment
• Shortest-path to the prefix• Equal Cost MultiPath (ECMP)-aware
• Global Segment
• Label = 16000 + Index• Advertised as index
• Distributed by ISIS/OSPF/BGP
1 2
3 4
5
16004
16004
16004
16004
16004
16004
16004
1.1.1.4/32
All nodes use default SRGB
16,000 – 23,999
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Adjacency segment
• Forward on the IGP adjacency
• Local Segment
• Advertised as label value
• Distributed by ISIS/OSPF
• But only local adjacency SID’s are installed in FIB!
1 2
3 4
524024
24025
Adj to 5
Adj to 4
All nodes use default SRGB
16,000 – 23,999
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SR operations illustration• Steer traffic on any path through the
network
• Path is specified by list of segments in packet header, a stack of labels
• No path is signaled
• No per-flow state is created
• IS-IS, OSPF, BGP all supported
Node Z56056
1 3 5 7
2 4 6 8
101
Payload to Z
16101
56056
16005
Payload to Z
16101
56056
16005
Payload to Z
16101
56056
Payload to Z
16101
Payload to Z
16101
Payload to Z
Goal: Go to Z but avoid node 7
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Incremental Deployment Use-Cases
© 2016 Cisco and/or its affiliates. All rights reserved. Cisco Public
SR Innovation VPN /
Service
Transport
Topology
Independent
IP FRR
Traffic
Engineering
Egress
Peering
Engineering
Data Center
Fabric
Microloop
Avoidance
Demand
Matrix
Application
Engineered
Routing
Inter-Domain
Policy at
ScaleIncremental
Use Case
Deployment
http://blogs.cisco.com/sp/supercharge-your-network-with-segment-routing-innovations
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SR Innovation Topology
Independent
IP FRR
Traffic
Engineering
Egress
Peering
Engineering
Data Center
Fabric
Microloop
Avoidance
Demand
Matrix
Application
Engineered
Routing
Inter-Domain
Policy at
ScaleIncremental
Use Case
Deployment
VPN /
Service
Transport
http://blogs.cisco.com/sp/supercharge-your-network-with-segment-routing-innovations
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Inter-Domain Policy at Scale
draft-filsfils-spring-large-scale-interconnect
© 2016 Cisco and/or its affiliates. All rights reserved. Cisco Public
Use-Case Description
• Segment Routing use-case aiming to scale the network to support hundreds of thousands of network nodes, and tens of millions of physical underlay endpoints
• Applicable to the interconnection of massive-scale DC's and/or large aggregation networks
• Principles are equally applicable to a network of any size
vPE1 ToR Spine LSR LSR vPE2ToRSpineLSR
DC A1 METRO A METRO BWAN DC B2
Datacenter Datacenter
Metro Metro
Core
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SRGB and SID allocation
• Homogenous end-to-end SRGB for simplicity
• Globally Unique Prefix SIDs for devices WAN and Metro domains
• Locally Unique Prefix SIDs for Datacenters
vPE1
20001
ToR
20002
Spine
20003LSR
17002LSR
16003
vPE2
20001
ToR
20002Spine
20003LSR
18002
DC A1 METRO A METRO BWAN DC B2
20k-24k 20k-24k
17k-18k 18k-19k
16k-17k
16k-24k
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IGP/SR within WAN and Metro Domains
• Each domain runs ISIS/OSPF SR
• Incremental deployment and seamless interworking with LDP
DCI1
17001LSR
17002LSR
16003
DCI2
18001
LSR
18002
METRO A METRO BWAN
IGP / SR 2 IGP / SR 3IGP / SR 1
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Segment Routing in the Datacenter
• Datacenter fabric runs BGP SR
• Example: 20006 is the BGP Prefix SID to DCI6
• ECMP-aware
• Simple (no LDP/RSVP)
• Policy-driven
vPE1
20001
ToR2
20002
Spine4
20004
Leaf3
20003DCI6
20006
vPE11
20011
ToR12
20012
Spine14
20014
Leaf13
20013Leaf15
20015
DCI16
20016
AS2
AS11
AS3 AS4 AS5 AS6AS1
Leaf5
20005
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Inter-Domain Policy at ScaleSR connectivity across domains
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Intra-Domain Routing – DC A1 and DC B2
• BGP SR in the DC
• Often eBGP would be used but iBGP can also be used (see tutorial)
• Smart AS (ClusterID) allocation in eBGP (iBGP) provides automated path filtering (see tutorial)
vPE1
20001
ToR
20002
Spine
20003LSR
17002LSR
16003
vPE2
20001
ToR
20002Spine
20003LSR
18002
DC A1 METRO A METRO BWAN DC B2
vPE1/32
NH: vPE1
BGP-LU LABEL: POP
PREFIX-SID: 20001
(relative 4001)
vPE1/32
NH: TOR
BGP-LU LABEL: 20001
PREFIX-SID: 20001
(relative 4001)
vPE1/32
NH: SPINE
BGP-LU LABEL: 20001
PREFIX-SID: 20001
(relative 4001)
DCI2/32
NH: DCI2
BGP-LU LABEL: POP
PREFIX-SID: 18001
(relative 2001)
DCI2/32
NH: SPINE
BGP-LU LABEL: 18001
PREFIX-SID: 18001
(relative 2001)
DCI2/32
NH: TOR
BGP-LU LABEL: 18001
PREFIX-SID: 18001
(relative 2001)
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Intra-Domain Routing – Metro A and Metro B
• In a metro, BGP/SR or ISIS-OSPF/SR are likely, both illustrated here
• Example: Metro A: BGP/SR
• Example: Metro B: ISIS/SR
vPE1
20001
ToR
20002
Spine
20003LSR
17002LSR
16003
vPE2
20001
ToR
20002Spine
20003LSR
18002
DC A1 METRO A METRO BWAN DC B2
DCI1/32
NH: DCI1
BGP-LU LABEL: POP
PREFIX-SID: 17001
(relative 1001)
DCI1/32
NH: LSR
BGP-LU LABEL: 17001
PREFIX-SID: 17001
(relative 1001)
ISIS LSP of AGG2
Leaf: Agg2
PREFIX-SID: 16002
(relative 2)
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Intra-Domain Routing – WAN
• ISIS / OSPF SR in WAN
• During a migration, benefit from SR seamless interworking with LDP and ship-in-the-night with RSVP
vPE1
20001
ToR
20002
Spine
20003LSR
17002LSR
16003
vPE2
20001
ToR
20002Spine
20003LSR
18002
DC A1 METRO A METRO BWAN DC B2
ISIS LSP of AGG1
Leaf: Agg1
PREFIX-SID: 16001
(relative 1)
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Inter-Domain Routing
• WAN aggs are re-distributed down to Metro and DC
• Nothing is redistributed up !!!
• How does vPE1 reaches vPE2?
vPE1
20001
ToR
20002
Spine
20003LSR
17002LSR
16003
vPE2
20001
ToR
20002Spine
20003LSR
18002
DC A1 METRO A METRO BWAN DC B2
WAN Aggs WAN AggsWAN AggsWAN Aggs
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Inter-Domain Routing
• Redistribution: from center to leaves
• WAN redistributes (only) its AGG’s into metro’s
• Metro redistributes (only) the WAN AGG’s into DC’s
• Redistribution: from leaves to center
• Nothing
vPE1
20001
ToR
20002
Spine
20003LSR
17002LSR
16003
vPE2
20001
ToR
20002Spine
20003LSR
18002
DC A1 METRO A METRO BWAN DC B2
ISIS LSP of AGG2
Leaf: AGG1
PREFIX-SID: 16001
(relative 1)
AGG1
NH: DCI2
BGP-LU LABEL: 16001
PREFIX-SID: 16001
(relative 1)
AGG1
NH: SPINE
BGP-LU LABEL: 16001
PREFIX-SID: 16001
(relative 1)
AGG1
NH: ToR
BGP-LU LABEL: 16001
PREFIX-SID: 16001
(relative 1)
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Inter-Domain Routing (Cont’d)
vPE1
20001
ToR
20002
Spine
20003LSR
17002LSR
16003
vPE2
20001
ToR
20002Spine
20003LSR
18002
DC A1 METRO A METRO BWAN DC B2
ISIS LSP of AGG1
Leaf: AGG2
PREFIX-SID: 16002
(relative 2)
AGG2
NH: DCI1
BGP-LU LABEL: 16002
PREFIX-SID: 16002
(relative 2)
AGG2
NH: SPINE
BGP-LU LABEL: 16002
PREFIX-SID: 16002
(relative 2)
AGG2
NH: TOR
BGP-LU LABEL: 16002
PREFIX-SID: 16002
(relative 2)
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Inter-Domain Policy at ScaleSR PCE
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SR PCE
• Multi-Domain topology
• Real-time reactive feed via BGP-LS/ISIS/OSPF from multiple domains
• Including ip address and SID
• Compute: stateful with native SRTE algorithms
vPE1
20001
ToR
20002
Spine
20003LSR
17002LSR
16003
vPE2
20001
ToR
20002Spine
20003LSR
18002
DC A1 METRO A METRO BWAN DC B2
Multi-Domain TopologySR PCE
Compute
Demo
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Circuit Optimization vs SR Optimization2
4
15
3
6
7
8 9
Classic TE is circuit-based
CSPF => non-ECMP path
SID List: {4, 5, 7, 3}
Poor ECMP, big SR list, ATM optimized
2
4
15
3
6
7
8 9
SR-native TE algorithms needed
Recognized Innovation - Sigcomm 2015
SID List: {7, 3}
ECMP, Small SR list, IP-optimized
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Four SR-native TE algorithms developed
• Metric optimization with inclusion/exclusion constraint and bound
• Metric: IGP metric, TE metric, extended TE-latency metric
• Inclusion/exclusion: IP address, SRLG, TE affinity, Link Loss
• Margin: any solution within the margin of the optimum is accepted
• Favor more ECMP or shorter SID list instead of insignificant optimization increment
• Also available on the router-based SRTE functionality
• Disjointness
• (A to Z) or ((A, B) to (Y, Z))
• With minimized latency diff, ECMP and shorter SID list
• (A to Z) also available on the router-based SRTE functionality
• Tactical BW optimization
• Multi-Constrained
• Sigcomm 2015 [url]
• Furthermore … TI-LFA and Microloop avoidance algorithms
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SR PCE - Fundamentally Distributed
• SR PCE not to be considered as a single “God” box
• SR PCE deployment model more like BGP Route Reflectors
• Different vPE’s can use different pairs of SR PCE’s
• SR PCE preference can either be based on proximity or service
vPE1
20001
ToR
20002
Spine
20003LSR
17002LSR
16003
vPE2
20001
ToR
20002Spine
20003LSR
18002
DC A1 METRO A METRO BWAN DC B2
SR
PCE
SR
PCE
SR
PCE
SR
PCESR
PCE
SR
PCE
SR
PCE
SR
PCE
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Inter-Domain Policy at ScaleOn-Demand SR Next Hop (ODN)
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Service Provisioning
• vPE1 learns about a service route with nhop vPE2
• RR shown could be any flavor of overlay controller
• How does vPE1 reach the nhop?
• vPE1 only has routes within DC A1 and to the AGG’s of the WAN domain
• Solution: On-Demand SR Next Hop (ODN)
vPE1
20001
ToR
20002
Spine
20003LSR
17002LSR
16003
vPE2
20001
ToR
20002Spine
20003LSR
18002
DC A1 METRO A METRO BWAN DC B2
BGP
RR2: V via vPE2
VPN-LABEL: 99999
1: V via vPE2
VPN-LABEL: 99999
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On-Demand SR Next-HopOverview
• When the vPE’s does not have any RIB entry for the (locator, policy), the On-Demand SR Next-Hop automatically sends a stateful PCEP request to the SR PCE
• Key benefit: provide the glue between the overlay and underlay controllers while decoupling them
• E.g. overlay controller does not need to react to multi-domain underlay topology change, nor compute TE policies
• E.g. underlay controller does not need to be involved in service orchestration, does not store any a priori TE policy
• E.g. no direct API or coupled workflow between the controllers
vPE1
20001
ToR
20002
Spine
20003LSR
17002LSR
16003
vPE2
20001ToR
20002Spine
20003LSR
18002
DC A1 METRO A METRO BWAN DC B2
SR
PCE
3: vPE2 ?
4: {SID List}
Demo
BGP
RR2: V via vPE2
VPN-LABEL: 99999
1: V via vPE2
VPN-LABEL: 99999
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On-Demand SR Next-HopReachability
• vPE1’s ODN functionality automatically request a solution from SR PCE
• Scalable: vPE1 only gets the inter-domain paths that it needs
• Simple: no BGP3107 pushing all routes everywhere
vPE1
20001
ToR
20002
Spine
20003LSR
17002LSR
1600316002
vPE2
20001ToR
20002Spine
2000318001LSR
18002
DC A1 METRO A METRO BWAN DC B2
SR
PCE
3: vPE2 ?
4: {16002, 18001, 20001}2: V via vPE2
VPN-LABEL: 99999
1: V via vPE2
VPN-LABEL: 99999
Demo
BGP
RR
BRKRST-3122 37
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On-Demand SR Next-HopSLA enabled
• Inter-domain SLA with scale and simplicity
• No RSVP, no midpoint state, no tunnel to configure !!
vPE1
20001
ToR
20002
Spine
20003LSR
17002LSR
16003
vPE2
20001
ToR
20002Spine
20003LSR
18002
DC A1 METRO A METRO BWAN DC B2
SR
PCE
3: vPE2 with Low-
Latency?
4: {16001, 16003,
16002, 18001, 20001}
2: V via vPE2
VPN-LABEL: 99999
EXT-COM: LATENCY
1: V via vPE2
VPN-LABEL: 99999
EXT-COM: LATENCY
Demo
BGP
RR
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Anycast SID’s for pairs of border nodes
• Anycast SID’s provide for better ECMP and High Availability
vPE1
20001
ToR
20002
Spine
20003
LSR
17002
LSR
16003
vPE2
20001
ToR
20002
Spine
20003
LSR
18002
DC A1 METRO A METRO BWAN DC B2
17901 16901 16902 18901
16902 1890117901 16901
16902 1890117901 16901
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On-Demand SR Next-HopReachability with Anycast SID
• Better load-balancing: ECMP across border routers
• Better availability: sub-50msec upon remote aggregation router failure
• Better control plane scalability: no PCE re-computation, no PCEP update, no FIB update
vPE1
20001
ToR
20002
Spine
20003LSR
17002LSR
16003
ToR
20002Spine
20003LSR
18002
DC A1 METRO A METRO BWAN DC B2
SR
PCE
3: vPE2 ?
4: {16902, 18901, 20001}
16902 18901
vPE2
20001
2: V via vPE2
VPN-LABEL: 99999
1: V via vPE2
VPN-LABEL: 99999
16902 1890117901 16901
16902 1890117901 16901
BGP
RR
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Binding SID to stitch Policies
• End-to-end policies can be composed from more basic ones
• An SRTE policy is bound by default to a Binding SID
• RSVP-TE tunnels can also be bound to a Binding SID and hence RSVP-TE tunnels can be used within an end-to-end SR policy
• Shorter SID list and churn isolation between domains
• Even if the WAN-MetroA sub-path changes, the related Binding SID 4001 is constant
vPE1
20001
ToR
20002
Spine
20003LSR
17002LSR
16003
vPE2
20001
ToR
20002Spine
20003LSR
18002
DC A1 METRO A METRO BWAN DC B2
SR
PCE
2: vPE2 with Min LAT?
1: REPORT {16003, 16002, 18002, 18001}, UP,
BindingSID 4001
3: REPLY {16001, 4001, 20001}
instead of
{16001, 16003, 16002, 18002, 18001, 20001}
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Seamless Transition
• Best-effort reachability could be provided by BGP3107
• ODN and SRTE / PCE provides interdomain reachability with SLA requirements
• Eventually, migration of more/all services over SR PCE
vPE1
20001
ToR
20002
Spine
20003LSR
17002LSR
16003
vPE2
20001
ToR
20002Spine
20003LSR
18002
DC A1 METRO A METRO BWAN DC B2
SR
PCE
3: vPE2 with Low Latency?
4: {16001, 16002, 18001, 20001}
BGP
RRvPE2/32 via DCI2
PREFIX-SID: 20001DCI2/32 via AGG2
PREFIX-SID: 180012:
vPE2/32 via DCI2
PREFIX-SID: 20001DCI2/32 via AGG2
PREFIX-SID: 18001
1:
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Inter-Domain Policy at ScaleInter-Domain Disjoint Services
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Example: Two Disjoint Inter-domain PW’s
• ODN/SR-PCE automated compute disjoint paths for PW1 and PW2
• PW1 and PW2 do not share the same headend, neither the same tailend
• Inter-domain SLA with scale and simplicity
• No RSVP, no midpoint state, no tunnel to configure !!
SR
PCEvPE2 disjoint group 7
{20003, 16001, 16002,
18001, 20001}
vPE22 disjoint group 7
vPE1
20001
ToR2
20002
Spine3
20003LSR
17002LSR
16003
vPE2
20001
ToR3
20002Spine4
20003LSR
18002
DC A1 METRO A METRO BWAN DC B2
vPE11
20011
ToR12
20012
Spine13
20013vPE22
20021
ToR23
20022Spine24
20023
{20013, 16011, 16012,
18011, 20021}
PW1
PW2
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Example: Inter-Domain PW - Disjoint Primary / Backup paths
• ODN/SR-PCE automatically computes disjoint primary/sec paths for the PW
• sBFD runs at 3x50msec on each SRTE path
• Upon failure detection of the primary, the secondary SRTE Path is used
• Inter-domain SLA with scale and simplicity
• No RSVP, no midpoint state, no tunnel to configure !!
vPE1
20001
ToR
20002
Spine1
20003
DCI1
17001
17901
LSR
17002
AGG1
16001
16901
LSR
16003
AGG2
16002
16902
vPE2
20001
ToR
20002Spine
20003
DCI2
18001
18901
LSR
18002
DC A1 METRO A METRO BWAN DC B2
DCI11
17011
17901
AGG11
16011
16901
AGG12
16012
16902
DCI11
18011
18901
Spine2
20004
Spine2
20004
SR
PCE1
Primary
1: Two disjoint paths to vPE2
2: PRIMARY: {17001, 16001, 16003,
18001, 20001}
SECONDARY: {17011, 16011, 16013,
18011, 20001}
Pri
Sec
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Topology Independent LFA (TI-LFA)
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TI-LFA - Benefits
• 50msec Protection upon local link, node or SRLG failure
• Simple to operate and understand
• automatically computed by the router’s IGP process (ISIS and OSPF)
• 100% coverage across any topology
• predictable (backup = post convergence)
• Optimum backup path
• leverages the post-convergence path, planned to carry the traffic
• avoid any intermediate flap via alternate path
• Incremental deployment
• also protects LDP and IP traffic
BRKRST-3122 47
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Automated Per-Destination optimization
• 2’s computes a primary path to 5
100 100
PE4 5
2 31
6 7 8
Source
Dest2Default metric: 10
FIB of 2 for destination 5
Incoming Label: 16005
Primary: SWAP 16005 for 16005, oif: 3
Demo
BRKRST-3122 48
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Flexible Link vs Node vs SRLG protection
• 2 checks the protection preference for the primary interface of the destination
• Link protection (illustration assumption)
• Node protection
• SRLG protection
100 100
PE4 5
2 31
6 7 8
Source
Dest2Default metric: 10
Demo
BRKRST-3122 49
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Automated and Optimum
• 2 computes the post-convergence path if the preferred failure would occur
• Optimality: the operator planned and dimensioned the post-convergence path to carry the traffic in the failure case
• 2 uses SR to encode the post-convergence path in a loop-free manner
• 2 updates the FIB with the backup path to 5
100 100
PE4 5
2 31
6 7 8
Source
Dest2Default metric: 10
FIB of 2 for destination 5
Incoming Label: 16005
Primary: SWAP 16005 for 16005, oif: 3
Backup: SWAP 16005 for 16005, PUSH 16007, oif: 6
Demo
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© 2016 Cisco and/or its affiliates. All rights reserved. Cisco Public
Do we need many SID’s? No!
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Microloop Avoidance
© 2016 Cisco and/or its affiliates. All rights reserved. Cisco Public
Microloops are a day-1 IP drawback
• IP hop-by-hop routing may induce microloop at any topology transition
• Link up/down, metric up/down
Upon link down convergence
Illustration for the post-convergence microloop
impacting traffic from 1 to 9 after link45 going
down. Default link metric 10
2 3 4
5
8 7 6
1
1000
9
Pre-convergence Path
Post-convergence Path
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© 2016 Cisco and/or its affiliates. All rights reserved. Cisco Public
SR Microloop Avoidance
• Prevent any microloop upon isolated convergence due to
• link up/down event & metric increase/decrease event
• 2-stage convergence
• Stage 1: non-looping SID lists to implement the post-convergence path
• Stage 2: post-convergence path
• If multiple back-to-back convergences, fall back to native IP convergence
FIB @ 1 for Destination 9
Initially: {16009} OIF 2
Stage1: {16006, 24065, 16009}
Stage2: {16009} OIF 8
2 3 4
5
8 7 6
1
1000
9
Pre-convergence Path
Post-convergence Path
Explicit Post-convergence Path
microloop avoidance segment-routing
Demo
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© 2016 Cisco and/or its affiliates. All rights reserved. Cisco Public
Illustration – Link Down
• No microloop can occur thanks to the 2-stage convergence and the use of non-looping SID lists to implement the post-convergence path in stage1
2 3 4
5
8 7 6
1
Default link metric 10
1000
Pre-convergence Path
Post-convergence Path
FIB @ 1 for Destination 9
Initially: OIF to 2
Stage1: {16006, 24065, 16009}
Finally (stage2): OIF 8
9
FIB @ 8 for Destination 9
Initially: OIF to 1
Stage1: {16006, 24065, 16009}
Finally (stage2): OIF 7
FIB @ 7 for Destination 9
Initially: OIF to 8
Stage1: {16006, 24065, 16009}
Finally (stage2): OIF 6
FIB @ 6 for Destination 9
Initially: OIF to 7
Stage1: {24065, 16009}
Finally (stage2): OIF 5
Illustration for the post-convergence
microloop impacting traffic from 1 to 9
after link45 going down
Demo
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Conclusion
© 2016 Cisco and/or its affiliates. All rights reserved. Cisco Public
Conclusion
• Functionality never seen before
• SR is fundamental architecture for modern IP network
• Unified Fabric with Policy through DC, Metro and WAN
• Simplification through Automation and protocol removal
• Strong operator endorsement
• Multi vendor consensus
• Impressive deployment and velocity
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© 2016 Cisco and/or its affiliates. All rights reserved. Cisco Public
Resources• Stay Informed - Tutorials, Conferences, IETF, Open-source SW
• http://www.segment-routing.net/
• Join us – Segment Routing @ LinkedIN
• Get in Touch
• “Latest” SR Demonstrations
• On-demand Next-Hop and SR PCE
• TI-LFA Node protection
• Microloop Avoidance
• SRv6 “Spray” use-case
• Segment Routing book
• Pre-order available now!
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© 2016 Cisco and/or its affiliates. All rights reserved. Cisco Public
Complete Your Online Session Evaluation
Don’t forget: Cisco Live sessions will be available for viewing on-demand after the event at CiscoLive.com/Online
• Give us your feedback to be entered into a Daily Survey Drawing. A daily winner will receive a $750 Amazon gift card.
• Complete your session surveys through the Cisco Live mobile app or from the Session Catalog on CiscoLive.com/us.
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© 2016 Cisco and/or its affiliates. All rights reserved. Cisco Public
Continue Your Education
• Demos in the Cisco campus
• Walk-in Self-Paced Labs
• Lunch & Learn
• Meet the Engineer 1:1 meetings
• Related sessions…
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© 2016 Cisco and/or its affiliates. All rights reserved. Cisco Public
Segment Routing opportunities at CiscoLive!
• BRKRST-2124: Introduction to Segment Routing
• Presented Monday – view session materials on CiscoLive.com
• LABSPG-2012: Next Generation Service Provider Network using Segment Routing & BIER
• In the Walk-in Self-Paced (WISP) lab area of the hub until 5pm today!
• BRKDCN-2050: Segment Routing in Datacenter using Nexus 9000 and 3000
• At 1pm today! South Pacific B, Lower Level
• LTRMPL-2104: Cisco WAN Automation Engine (WAE) Network Programmability with Segment Routing
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Thank you