SRV6 – DEPLOYMENT CASE STUDYRegie Ginanjar
Network Architect – XL Axiata

Aditya Kaul
Principal Solution Architect – Juniper Professional Services
1© 2022 Juniper Networks

Juniper Public

AGENDA• SRv6 Industry Outlook•

Quick Update• SRv6 Deployment @ XL Axiata• SRv6 Design• Deployment Challenges• Future Goals

2© 2022 Juniper Networks

Juniper PublicSRV6 INDUSTRYOUTLOOKQUICK UPDATE

3© 2022 Juniper Networks

Juniper PublicSRv6: What’s all the hype about ? (vs MPLS)
Operational Simplicity: Stateless, Programmable, Single data plane across DC/Metro/Core,BGP Free Transport ( BGP-LU isn’t required for scaling the networks, DCI GW not required)High Availability: Reliable link/node protection with TI-LFA, Load-balancing with IPv6 flow
label

Scalability and Efficiency: IPv6 scale, Locator summarization, Longest Prefix Match (just likeInternet routing), Shim Less vs VxLAN/MPLS Label

Seamless Integration: IPv6 data plane, Non-SRv6 routers co-existence, can also leverage
6PE MPLS in absence of IPv6 Core, Seamless & Better Migration than MPLS à SR-MPLS

Application-aware routing: Applications can program SRv6 and define constraints as most of
the end Hosts & Applications support IPv64© 2022 Juniper Networks

Juniper PublicSRv6: Industry Standards & Evolution
Ready to consume
TI-LFA

VPN services

Prefix Summarization

SR Policy

Flexible Algorithm

OAM

SRv6-MPLS Interworking
Multicast: BIERin6, SR-P2MP

SRH Compression: CSID Flavors–NEXT-C-SID (uSID)

Still cooking

SRH Compression: CSID Flavors–NEXT-C-SID & REPLACE-C-SID
Inter-Op/Multiple data-plane (https://datatracker.ietf.org/doc/draft-ietf-spring-srv6-srh-compression/)
Multicast: Replication Segment (https://www.ietf.org/archive/id/draft-ietf-spring-sr-replicationsegment-16.txt)

Analytics & Telemetry: Sensors, Flows5© 2022 Juniper Networks

Juniper PublicSRv6 Multi-Vendor
Interop 2024

ACX5448-M
ACX7024
ACX71000-48L
MX10008
MX204
MPC10E
Paragon Insights
Paragon Pathfinder

MX304
PTX10004
QFX10002-72Q
QFX5110-48S
QFX5120-32C
QFX5120-48Y
QFX5210-64C

Cisco

Microchip

ZTE

ArrcusHuawei

Nokia

EricssonCalnexJuniper

RibbonCiena

Keysight

Spirent

2024
2024
SRv6 uSID•Juniper Participation

AristaSRv6 Micro Sid (uSID):•

GRT (uDT4, uDT6, uDT46)•L3VPN (uDT4, uDT6, uDT46)•

EVPN E-Line•

EVPN E-LAN•

EVPN T5•

SRv6 locator summarization•

SRv6 transposition•

SRv6 TE policies with explicitpaths•

SRv6 Flex-Algo•

Dynamic latency metric•

Admin groups•

FA constraints (maxlatency, min bandwidth,reverse affinity)

6© 2022 Juniper Networks

Juniper Public

High-level Transport Architecture
RAN 1CoreRAN 2

Network Telemetry
RAN2 BGP-LSController

RAN1 BGP-LS(v)RR(v)RRPS-PE
Home
MA1PAG1AG1HomeRegional Inline RR

Regional Inline RRCoreCoreAG2

PAG2MA2Biz

Biz
IPv6/SRv6

gNB

IPv6/SRv6

IPv6/SRv6
gNB

Multi-instance ISIS
L-ISIS L2 (RAN instance 1)

L-ISIS L2 (CORE instance)

SRv6

SRv6

SRv6/Flex Algo

SRv6-TE/Flex-Algo

L-ISIS L2 (RAN instance 2)

SRv6
SRv6/Flex-Algo

L3VPN/EVPN
8© 2022 Juniper Networks

Juniper Public

LOCATOR ADDRESSING DESIGN

9© 2022 Juniper Networks

Juniper PublicPrefix & Base Locator Summarization
CoreRegion 1

CSR

Area 49.000X
PAG1/48/48

L2
Area 40.X001
PAG2CSRPAG1AGAGCore

N x /48/40

N x /48/40/48/48
PAG2/40/40/40

N x /48/40Central/40/40/40/40

L2Area 40.X002

N x /48
N x /48

PEN x /48
N x /48

N x /48
N x /48

Sumatera

JavaN x /48

East10© 2022 Juniper Networks

Juniper PublicSRv6 <-> MPLS Interworking
Transport scenariosØØØProvide mechanisms for SRv6 domains to talk to SRv6 Domains Over IPv6 Networks
SRv6 ABRs to advertise SRv6 Aggregate locators across the SRv6 network
SRv6 domain can service constraints using color/flex-algo/SRv6-TE.

Gateway Interworking scenariosØØØProvides service routes interworking at SRv6/MPLS ABR/GW routers
SRv6 SID to Label mapping for both SRv6 to MPLS and MPLS to SRv6
Option-AB and Option-B scenarios for SRv6 ßà SRv6

IPv6/MPLS

Service RR

SRv6

MPLS

SRv6

SRv6

SRv6/MPLS
1111© 2022 Juniper Networks

Juniper PublicMobile: eNB (CSR-SRv6) <-> vEPC (PS-PE-MPLS)

CSR-SRv6 <-> PS-PE (4G L3VPN)
SRv6 Services in Production Network

Fttx VPWS: CSR (SRv6) <-> PS-PE (MPLS)Enterprise-EVPN : CSR (SRv6) <-> CSR(SRv6)
Enterprise-L3VPN : CSR (SRv6) <-> PE-ENC (SRv6)

SRv6/MPLS RAN <-> IPBB (SRv6)
CSR
VPWS

Enterprise-L3VPN : CSR (SRv6) <-> CSR (MPLS)SDN Controller

PAG

SRv6
ISIS-RAN

Network Telemetry

CSR
PAG

IW-GCoreAGAG

PE –ENC

SRv6
ISIS-RAN

GGC
L3VPN

eNB

IPv6/SRv6

eNB

GGC

IW-G
L3VPN

CSR
L2ckt

IP-MPLS

L3VPN

PS-PE

PAG

L3VPN

(v)EPC

PS-PE

L3VPN

AG

L3VPN

Core

CSR
PAG

AG
IP-MPLS

IP/MPLS
eNB

SRv6
ISIS-RAN© 2022 Juniper Networks

L3VPN

SRv6
ISIS-RAN
12Juniper Confidential

Key Architecture Enablers
ISIS Summary

ISIS Summary

B:1::/40

A:1::/40

Locator
Summarization

ISIS Agg X

ISIS Agg Y

ISIS Core

ISIS Metro A

Multi-instance ISISISIS Metro C
ISIS Agg X

ISIS Agg Y

ISIS Core

ISIS Metro B
ISIS Metro D

SID B <-> VRFA table mapping
Lookup SRv6 SID, push MPLS label

SRv6-MPLS
Interworking

Site A

MPLS

SRv6Site B

Interworking
Gateway© 2022 Juniper Networks

13

Juniper Confidential

SRV6 DEPLOYMENT• Experience & Challenges

14© 2022 Juniper Networks

Juniper Public

XL Axiata: SRv6 Background andDesign Objectives
Challenge•••

Multi-vendor, Brown-field fragmented network.
Most of the equipment lacking SRv6 capability.
Ongoing 5G rollout plan and deadlines.

ApproachPragmatic• Leverage existing install base.Co-existence of old and new platforms for
speedy rollout and minimal disruption.
• Dual-stack first, enable SRv6 where possible and interwork with MPLS for
service and business continuity.
• Focus on the network transformation first, SDN later.

Netconf/YANG

PCE
LDP

BGP

BGP

BGP-LURSVPOutcomes•••

Architecture simplification using SRv6.
SRv6 scales the network for 5G expansion.
Future use-cases: Network slicing, Edge Compute, Dynamic trafficengineering.

LDP

IGP with SRv6IGPMPLS

IPv6CurrentTarget15© 2022 Juniper Networks

Juniper PublicChallenges deploying SRv6 Design in a Multi Vendor
Environment….
XL Axiata has deployed Multi-Vendor SRv6 Network across Huawei, Cisco, ZTE & Juniper platforms

Complex Brownfield
Deployment & IOT

Lack of SRv6 Skills
Specialized Skills
compared to existing
MPLS skills
Different
terminology vs MPLS
Distinct bestpractices, different
than MPLS… per vendor

Long DesignValidation cycle forMulti Vendor IOT

Inconsistent Ops
during Co-existence
Multiple data plane(MPLS & SRv6)
Troubleshooting
overhead in Hybridstate

Hybrid Model, MPLS
in some sites andSRv6 at new sites

Inconsistent network
behavior due to SRv6
Summarization

Business Applications
across hybrid
ecosystem

Siloed visibility in somecases due to absence ofconsistent SRv6 OAM… prevents optimal
service delivery… hinder IT operations
performance

Platform Limitations
Capabilities
Different capabilities
across different
vendors (SRv6compression)
Some vendors werenot IETF compliant
Software Roadmap
variations acrossdifferent platforms &vendors… limits problemsolving

Controlling costs
Extendeddeployment scheduledue to feature gaps
Multiple cost reports
per vendor/region
TTM for newproducts constrained
due to SRv6
Migration
Additional Opex
… leads tounpredictable costs

16© 2022 Juniper Networks

Juniper PublicMulti Vendor SRv6 IOT

Key “considerations” for a successful multi-vendor SRv6 deployment• Plan Addressing based on GUA or ULA – Design Pre-requisite

12Locator
AddressingServices• IPv6 Infrastructure (GUA) and SRv6 Locator (ULA) as a potential option• SRv6 Locator Block Length – Plan ahead based on the vendor mix• Different Vendors might have a preference based on their compression solution• Next-C-SID prefers 16, 32 and 48• Replace-C-SID prefers 48, 56, 64, 72 and 80• Global Internet, L3VPN and EVPN services over SRv6 transport (SRv6 BGP
based Overlay services RFC9252)• SRv6 SID Structure sub-sub-TLV• Plan, verify and validate the use of sub-sub TLV for L3 & L2 services• SRv6 OAM – Plan for Standardized OAM toolkit which’ll work across vendors

3 ”P” Approach3Interworkingwith MPLS

• Plan for Seamless Interworking with existing MPLS Transport & Services• Co-Existence with MPLS or the use of single IPv6 data plane• SRv6 <> MPLS L3VPN Interworking Gateway functionality• SRv6 <> MPLS Interdomain Solution

17© 2022 Juniper Networks

Juniper Public

XL Axiata SRv6 Network….the good after the 3-year
journey

Cost
Optimization

VLAN
VLAN

APP

Enterprise
SD-WAN

APP

Datacenter

Low Latency Services
VLAN

Programmability
Close Loop
Automation

DevOpsNetOps

Massive Scale&Flexibility

VLAN

XL Axiata

APP

APP

ConsumerEnterprise

VPCVPCAny Service
AnywhereAPP

Existing
on-premises
services

Public Cloud

MobilePacket CoreCDN
Networks

EastAPP

Public Cloud18© 2022 Juniper Networks

Juniper Public

FUTURE GOALS

19© 2022 Juniper Networks

Juniper PublicSRv6 Deployment Goals 2024
SRV6 Deployment

Title

Automated Service
Prioritization

Title
Smarter BandwidthUtilization•••

SRv6 Compression – NEXT-CSID based Services (DT46/DX2/DT2)
SRv6 <> MPLS Interworking Option B
Flex-Algo
Deployment with Delay “Metric” using Twamp-Lite ( Multi-Vendor-Juniper,• Content
Cisco,• ZTE& Huawei)
Content•••

Ensure customer SLAs are delivered
Link Delay Measurement and Delay Based Routing• Content
GranularService Prioritization.
• Content• Content•••Utilize inter-region links more efficiently
Allow all traffic to use optimal paths; re-grade based on Link utilization and congestion.
Intelligently
congest inter-region links and maintain SLAs.
• Content• Content• Content
END.DT46 – L3VPN, Global
END.DX2 – EVPN-VPWS
END. DT2 – EVPN-ELAN ( Multi-Vendor-Juniper, Cisco, ZTE & Huawei)

TitleServices•••20© 2022 Juniper Networks

Juniper PublicNEXT-CSID - uSID
• SRH requirement for TI-LFA / TE will be minimized (potentially even removed for typical TI-LFAapplications, or less advanced TE) with uSID (NEXT-CSID), where multiple SIDs can be embedded
in single 128-bit address field. https://www.ietf.org/archive/id/draft-ietf-spring-srv6-srh-compression-13.txt– Example: /32 allocated to the operator, 100k nodes, 5 slices (flex-algo), 5 Regions• Per region SRv6 locators à 16 bits (216 = 65,536) from address space enough for 100k locators à SRv6 locator is /48 (32+16)• 128 – 48 = 80 bits left for uSID and FUNC:ARG• 16-bit long uSID à 16 bits left for FUNC:ARG

Operator’s SRv6 assignment/32

SRv6 locator

/48

/112

uSID-1

uSID-2

Node location (part of the SRv6 address
to uniquely identify the node)uSID-3SRv6-TE/TI-LFA SIDs

00:00
End-of Carrier/128

FUNC:ARG

Service SID (à laservice ‘label’in SR-MPLS)

21© 2022 Juniper Networks

Juniper PublicSRv6 Network Slicing
Slice ID in the SID• SRv6 Locator, or SRv6 SID (END.DT4, END.DT6, END.DT46) can have dedicated space (few bits) to carry
Slice ID (see below some examples )• Transit router classifies packets to appropriate slice based on this slice ID and puts the packet to the slice on
the link, where each slice on the link has capacity guarantees.

16 bits

FD

30

SRv6 Locator

FunctionArguments

48 bits

32 bits

48 bits

32 bits

48 bits

8 bits4 bits 4 bits 4 bits 4 bits

Slice -ID

Flex Agg ID Pre- Reser
Agg ID ved
Algo

8 bits

NE-ID Fun

ct

ion

Reser

FD

30

Flex-Algod

SRv6 Locators

32 bits

96 bits
16 bitse

Function: Arguments

SRv6 Locator
16 bitsv

16 bits

48 bits

4 bits 4 bits
SliceIDNE-IDReserv

eVPN

24 bits

R e s e r v e d

SRv6 Locatorsd22© 2022 Juniper Networks

Juniper PublicFlex-Algo: Low Latency / Service Diversity• Separate Routing Planes with Geographical or Service Diversity Constrains• Low Latency using Link Delay Metric (ISIS Twamp-Lite)23© 2022 Juniper Networks

Juniper Public

Using Flex-Algo with Delay-Metric in Action• PE1 chooses least metric blue path to PE2 by default• PE1 chooses least delay-metric green path to PE2 in Algo 129• Default metric is 10• Some links use static delay-metric of 20ms
• Other links use TWAMP light dynamic delay-metric calculation• All devices participate in SRv6 Algo 129

24© 2022 Juniper Networks

Juniper PublicEVPN over SRv6 with SRv6 SRH / uSID
EVPN VPWS

EVPN
EVPN

EVPN - VPWS

SRv6 Tunnel

SRv6 Tunnel

EVPN service covers:
End.DT4/DT6/DT46 – Layer 3 table lookup
End.DX2U - Layer 2 unicast castEnd.DT2M – Layer 2 flooding

EVPN VPWS service covers:
End.DX2 - Layer 2 cross connect25© 2022 Juniper Networks

Juniper PublicSummary
SRv6 Evolution

12

Deployment experience

3Future Use-caseStandards areevolving fastInter-op testingis keyNW Slicing, Edge DC
and more …

Join the standardization efforts

Plan, Test and Validate

Bring Your Own Use-case26© 2022 Juniper Networks

Juniper Public

27© 2022 Juniper Networks

Juniper Public

Guaranteed Link – Network Slicing
Link Channelization/Partitioning with SLA§ Match for Slice-ID
In SRv6 SID

Traffic directionslice enforcement(output)

Slice selection(input)

See following blogs for more details:
https://community.juniper.net/blogs/krzysztofszarkowicz/2023/05/12/link-slicing-with-mplsand-srv6-underlays
https://community.juniper.net/blogs/krzysztofszarkowicz/2023/07/30/link-slicing-with-mplsand-srv6-underlays-part-2

CIR

PIR

transmit-rate

shaping-rate

Slice

CIR

PIR

transmit-rate

shaping-rate

PIR

EF Queue Scheduler

PIR

NC Queue Scheduler CIR

PIR

AF Queue Scheduler CIR

PIR

CIR

BE Queue Scheduler CIR

PIR

Slice-A Traffic Control Profile

EF Queue Scheduler

PIR

AF2 Queue Scheduler CIR

PIR

AF1 Queue Scheduler CIR

PIRCIRBE Queue Scheduler CIR

PIR

Slice-B Traffic Control Profile

EF Queue Scheduler

PIR

AF2 Queue Scheduler CIR

PIR

PIR

AF1 Queue Scheduler CIR

PIRCIRBE Queue Scheduler CIR

PIR

Slice-C Traffic Control Profile

EF Queue Scheduler

PIR

AF2 Queue Scheduler CIR

PIR

AF1 Queue Scheduler CIR

PIR

BE Queue Scheduler CIR

PIR

CIR

PIR

PIR

Slice-D Traffic Control ProfilePort

IFD Traffic Control ProfileQueue§ Slice granularity§ Unused capacity sharing28© 2022 Juniper Networks

Juniper Public