Service Chaining for Fixed Mobile Networks

Prakash Suthar – Principal Architect, Cisco Systems

Ajay Simha – Sr. Architect, Cisco Systems

BFKSPM-2021

• Introduction

• SDN and Service Chaining Overview

• Service Chaining Solutions

• Use Cases

• Conclusion

Agenda

Introduction

National Core

(IP/MPLS)

SP Network Architecture

Aggregation

(IP/MPLS)

Internet,

AG-1

CSR

CSR

CSR

AG-1

AG-1

AG-1

FTTH

Video

VAS, Subscriber Mgmt

Main DC

WiFi Access

Point

CSR

Residential

STB

CPE

WiFi Access

Point

OLT

MAG PGW

LMA

Application

ServerApplication

ServerApplication

Server

SCIM (AS Orchestration)

AP

PLI

CAT

ION

LA

YER

HSS

SE

RVI

CES

LAYE

R

S-CSCF

I-CSCF

P-CSCF BGCFRx

Cx

Sh

Cs

ISC

Billing, Media Server, Messaging

IMS Core

WLC

CDN Headend

Video CMS

Content Adaptation

ISG

PCRF/AAA

BNG

Regional DC/Distributed Service Edge

WLC

iWAG1

3

2

Transport

(DWDM)

CSR – Cellsite router, AG-1, AG-2, AG-3 – Tiered Aggregation Routers

MAG- Mobile Access Gateway, LMA – Local Mobility Anchor

PGW – PDN Gateway

FTTH – Fiber to the home, OLT – Optical Line Terminator

BNG – Broadband Gateway

AG-2AG-3

What are the Typical Service Chaining Appliances?

Firewall and NAT

Deep Packet Inspection (DPI)

L7 Application Services

- Translates private IP address of mobile device to one that is publicly routable

- Protects the IP address of mobile device from network initiated connections which drain battery and could be viral attacks

- Provides critical intelligence around application and protocol usage

- Enforces a discipline of “network management” consistent with fair use policies

- Media delivery optimization (for video and web content)

- URL Filtering e.g. parental control, differential billing, freebee

- Content portals

- Location based/personal services, Policy engagement (e.g. clientless network – subscriber interaction for micro-transactions)

Mobility Service Chaining (Gi-LAN)

“The Gi-LAN is the domain of the network that straddles the boundary between the mobile network and data networks such as the Internet”

• The acronym “Gi” is the name of the 3GPP reference point (it is SGi for LTE)

• What is typical?

• Appliances from multiple vendors (good) are hardwired restricting flexibility (bad)

• Significant cost to engineer and architect

• Packets are classified by APN, without leveraging the power of the policy layer

Access GGSN/PGW

12ABC

3DEF

4GHI

5JKL

6MNO

7

PQRS

8TUV

9

WXYZ

*0#

Signal Strength

DPI

AP

N DPIDPI DPIL7 AF DPINATFW

DPI

AP

N DPIDPI VO DPINAT

DPI

AP

N SBC

AP

N

The Gi-LAN infrastructure today is static and rigid and offers little in the way of subscriber-awareness!

This problem needs fixing!

Evolution of GiLAN - Subscriber ServicesWe are at the 3rd Inflection Point in a Shifting MarketWave 1

1st inflection point (2000 - 2010)

Operators buy purpose-built elements which are then inter-connected

as chained services

APN Based classification

Services “hardwired” into APNs

Wave 2 2nd inflection point (2010 - 2015): services steering

The need for increased granularity in subscriber policies is

addressed with “services steering” boxes (repurposed

routers / DPIs / TDF)

Cloud orchestration

Access GGSN/PGW

12ABC

3DEF

4GHI

5JKL

6MNO

7

PQRS

8TUV

9

WXYZ

*0#

Signal Strength

AP

N

PCRF

Slice

BGP

SDN

Wave 3 3rd inflection point (2014 - future): virtualization

Virtualized appliances instead of physical element

SDN-based service chains instead of hard-wired cabling

COTS hardware; router only as load balancer

CAPEX/OPEX efficient

Access GGSN/PGW

12ABC

3DEF

4GHI

5JKL

6MNO

7

PQRS

8TUV

9

WXYZ

*0#

Signal Strength

DPI

AP

N DPIDPI DPIL7 AF DPINATFW

AP

N

DPI L7 AF FW

PCRF

Architecture Principles for (S)Gi-LAN Evolution

• SDN & Next Gen Data Center

• Service Chaining Layer

• Slicing & Load Balancing

• Subscriber Policy Management

• Management Plane (Mgt)

• Life Cycle Management and Service Orchestration

New Building Blocks to be defined/implemented:

Data Plane

Con

tro

l P

lan

e

SDN & Data Center Fabric

Service Chaining

Slic

ing

Physical & Virtualized

(S)Gi Appliances

Subscriber Policy

Orchestration

SDN and Service Chaining Overview

• Improved Capital Efficiencies because of the Separation of Hardware & Software

• Flexibility in Assigning Virtualized Functions to Hardware

• Rapid Service Innovation via Software Development

• Improved Operational Efficiencies Through Adoption of Cloud Procedures

• Reduced Power via Cloud Techniques

• Open Environment

ETSI NfV Framework – Building Block for GiLAN

http://www.etsi.org/deliver/etsi_gs/NFV/001_099/002/01.01.01_60/gs_NFV002v010101p.pdf

Virtual Network Function (VNF)

Manager(s)

VNFM

NFV

Orchestrator

NFVO

Virtual

Infrastructure

Manager(s)

VIM

NFVI

VNF

domain

Virtualization Layer

Hardware Resources

OSS/BSSOs-Ma

Or-Vnfm

Vi-Vnfm

Or-Vi

Ve-Vnfm

Nf-Vi

Descriptors

Se-Ma

VNF

E/NMS

VNF

E/NMS

Vn-Nf

Vi-Ha

SDN and Virtualization Environment

vGi-LAN

Foundation Services

API to abstract the IaaS functions

Virtual Storage

Application & VM Auto-build

Network/Compute/Storage

IaaS

Mediation

PaaS +

ServiceFunctions

SDN

Virtual Network

Virtual Compute

VoLTE

Orchestration Adapter

Orchestration Adapter

vPCRF

Orchestration Adapter

Packet Core

Orchestration Adapter

Openstack (or other IaaS) APIs

Physical

Telco Cloud Foundation Services

Fulfillment Portal

VNFCatalog

ServiceChain

Catalog

vGi-LAN

Apache Stratos

Jcloud API

Virtual Storage

Application & VM Auto-build

Network/Compute/Storage

IaaS

Mediation

PaaS

SDN

Virtual Network

Virtual Compute

VoLTE

Orchestration Adapter

Orchestration Adapter

vPCRF

Orchestration Adapter

QSB

Orchestration Adapter

Openstack (or other IaaS) APIs

Physical

Service

Functions

IETF Working Group - Service Function Chaining ArchitectureHigh-level Component Structure

• Architecture components• Service Chaining Orchestration

• Define service chains & build service paths

• Control / Policy Planes• Instantiate service chains adhering to policy

• Data Plane• Traffic steering & metadata

Service Chaining

Orchestration

SF

(VM)

Service

(v)s

witch

Forwarding

Service

Service

Classifier

SF

(Physical)

Serv

ice1

VLA

N

Service Function

Forwarder (SFF)

Control Plane

Policy Plane

SF

(VM)

Service

(v)s

witch

Forwarding

Service

SF

(Physical)

Serv

ice1

VLA

N

Service Function

Forwarder (SFF)

Service

Classifier

Network Overlay +

Service Header

Service Header

Service Chaining Solutions

Mobile

High Level Architecture

NAT

URL Enrichment

ParentalControl

LBSFx

Video/WebOptimizer

FW

LB

SFx

URL Enrichment

VideoOptimizer

FW

FW

NATSFx

Traffic Detection Function (TDF),Classification

And Load Balancing

Reverse Sticky

PCRF

InternetMobileAccess

Option-1 Standalone classifier

GiLAN Option-1 Architecture

SGC

Clas

sifie

r

vPath

Gx/Sd

PCRF

PRPC/Gx

Classifier

PGW/GGSN

Gx

WWW

vSG Slice

Protobuf

SGC-A vPath

CE CE

Gy/Gz

SCE ASA

SCE

ASA

SCE ASAHTTP

OCS/OFCS Orchestration and OAM

Openstack

KVM

Network Orch (VSM)

SDN Controller

(Policy Aware Controller)

SDN Classifier and

Service Chaining

Orchestration &

OAM

DPI

Clas

sifie

r VE

M

NAT/

FW

VEM

2

SGC-A

3

6

7

Internet

PCRF

FE VRF

TE VRF

SGC

5

4

10PGW 1

11

8

9

Slice

GiLAN Option-1 Packet Flow

0

IMSI

MSISDN

IPv4-Addr

IPv6-Addr

RAT-Type

….

IP CAN Session

Policy Rule=Gold

SC-Rule=SC_Gold

SCE-Rule=PKG_1

3GPP AVPs…..

SC_Gold (SPI Mapping)

• <*:*;*:80> = 1

• <*:*;*:443> = 2

SPI

1 = SCE1, ASA1

2 = ASA2

Service

SCE1 = 10.10.10.1

ASA1 – 10.10.11.1

ASA2 = 10.10.11.2

PKG_1• Block P2P

• Throttle free VOIP

GiLAN Prototype

MobileAccess

Class

FW/

NAT

HTTP Proxy

Internet

FW/NAT

HTTPProxy

FW/NAT

HTTPProxy

P-GW/GGSN

vPath in N1kv

Controller

PCRF

12ABC

3DEF

4GHI

5JKL

6MNO

7

PQRS

8TUV

9

WXYZ

*0#

Signal Strength

VideoOptimization

VPP / Load Balancer

pN

IC

pN

IC

vNIC

vNIC

vNIC

vNIC

pN

IC

pN

IC

SG Controller

vNIC

ASA1kv

pN

IC

pN

IC

HTTP Proxy

Physical Network

vNIC

vNIC

vNIC

vNIC

vNIC

PCRF

Internet

Distributed vSwitch

Access

Hypervisor+ Cluster SW

Bare Metal

OS

Appliance

Functional View Virtualization View

GiLAN System Instantiation

VEM-CClassifier

SGC-ASGC-A

SGC-ASGC-A

VEM-F

SCE INT NAT

VEM-F

SCE INT NAT

Forwarder

SCE Optimizer NAT

Networking

Openstack

Apache Stratos

vGiLAN app-managerOPWV OAM

OPWV VideoOPWV Video

OPWV Video

PCRF

SGC 0

0

0

1

22

2

4

35 5 5

67

Policy Optimizer Orchestration

SDN Service Chaining

Option-2 Mobile Gateway acts as

classifier

(S)Gi-LAN

SAEGW

Service Chaining

SF1

SF2

SFn

ASR9K(Internet)

ASR9K(RAN)

Slice 1

Slice 2LB1

LB2

……

LBm

PCRF

SDN Layer

Gi-LAN Orchestration & Service Assurance

Slice p

VNFA

VNFB

…

VNFA

VNFB

VNFA

VNFB

GiLAN Option-2 Architecture

(S)Gi-LAN

SAEGW

Service Chaining

SF1

SF2

SFn

ASR9K(Internet)

ASR9K(RAN)

Slice 1

Slice 2LB1

LB2

……

LBm

PCRF

SDN Layer

(S)Gi-LAN Orchestration & Service Assurance

Slice p

SDN & Data Center Fabric: ACI

Service

Function

Classifier:

Cisco vPC

(PCEF)

Slicing & Load

Balancing:

F5 BigIP VE

(LTM)

Service

Function

Forwarding

+ Gi-LAN

Services:

F5 BigIP

VE (PEM)

Service

Function

Forwarding

+ CGNAT

& FW:

F5 BigIP VE

(AFM)

Gi-LAN Orchestration: NSO + CTCM (Future)

Subscriber

Policy: CPS VNFA

VNFB

…

VNFA

VNFB

VNFA

VNFB

Service Functions

(Virtualized +

Physical)

Service Chaining: DSCP/VLAN (NSH in Future)

GiLAN Option-2 Functional View

GiLAN Option-2 Summary

• Stateless load-balancing front-end

• All Slices are active

• Slice Affinity for the Subscribers

• Keep established flows to selected slices when adding/removing slices or SFs (Avoid impact of ECMP re-hash on SAEGW)

• End to end user bi-directional stickiness • Determinist user mapping on a single

slice (Src routing)

• Better use of Cisco vPC with downstream mac-based forwarding (reduced inter SF routing on DI-LAN)

• Optimal user traffic within ACI Fabric

• No traffic hair-pinning to DCI Gateway

(S)Gi-LAN

SAEGW

Service Chaining

SF1

SF2

SFn

ASR9K (Internet)

ASR9K (RAN)

Slice 1

Slice 2 LB1

LB2

… …

LBm

PCRF

SDN Layer

(S)Gi-LAN Orchestration & Service Assurance

Slice p

VNFA

VNFB

…

VNFA

VNFB

VNFA

VNFB

compute-

node#1

Cisco vPC

Option-2 Service Chains Layout

ACI EPG

compute-node#2

1111

CGNAT1

VNFB

S1C31131

FE1LTM1

1001 1022

ASR9K

DCI-1

VNFA

S1C11112

1132

1121

compute-node#3

1211

CGNAT2

VNFB

S2C31231

FE2LTM2

VNFA

S2C11212

1232

1221

compute-node#4

1311

CGNAT3

VNFB

S3C31331

FE3LTM3

VNFA

S3C11312

1332

1321

SF1

SF2

SF3

1000

Option2 Service Chain CreationCurrent Implementation

VAS

S1C1N2

VAS

S1C1N1

S1C1N

1

VAS

S1C1N4

VAS

S1C1N3

S1C1N

2

S1C1N

3

VAS

S1C1N2

VAS

S1C1N1

S1C2N

1

VAS

S1C1N3

S1C2N

2

VAS

S2C1N2

VAS

S2C1N1

S2C1N

1

VAS

S2C1N4

VAS

S2C1N3

S2C1N

2

S2C1N

3

VAS

S2C2N2

VAS

S2C2N1

S2C2N

1

VAS

S2C2N3

S2C2N

2

VAS

S3C1N2

VAS

S3C1N1

S3C1N

1

VAS

S3C1N4

VAS

S3C1N3

S3C1N

2

S3C1N

3

VAS

S3C2N2

VAS

S3C2N1

S3C2N

1

VAS

S3C2N3

S3C2N

2

ACI EPG

CreateTenant($host, $login, $password,$tenant);

CreatePhysicalDomain($host, $login, $password, $physical, $vlan);

for ($i = 1; $i <=$slice; $i++) {

for ($j = 1; $j <= $chain; $j++) {

CreatePoolVlan($host, $login, $password, $i, $j, $vlan, $numEpg);

for ($k = 1; $k <= $numEpg; $k++) {

CreateBridgeDomain($host, $login, $password, $tenant, $bridge, $private, $i, $j, $k);

CreateEpg($host, $login, $password,$tenant, $profile, $epg, $bridge, $i, $j, $k);

}

}

}

CreateAttachableAccessEntityProfile($host, $login, $password, $aaep , $physical, $policy,

$infra, $profile, $selector, $fromCardNum, $numIntProfile, $nameCard, $srange, $fromPort, $toPort,

$nameSwitch);

APICPythonRequest

Cobra SDK

PHP5

Openstack/KVM – ACI Fabric

(S)Gi-LAN

SAEGW

SF1

SF2

SFn

ASR9K(Internet)

ASR9K(RAN)

Slice 1

Slice 2LB1

LB2

……

LBm

PCRF

Slice p

VNFA

VNFB

…

VNFA

VNFB

VNFA

VNFB• L3/L4 DSCP

marking – Chain #id, RAT, CP flag based on UE profile • Upstream: Up to 32 ECMP

SRC/DST• Downstream: Src Mac-

based reverse (SF<->LB stickiness)

• Subscriber Slice Affinity (based on Mobile IP address)

• Slice health monitoring• Intelligent session

placement• Graceful slice deactivation• DNS caching

• Chain health monitoring• DSCP based steering• L7 URL based steering• TCP Opt.

• CGNAT, Logging• Firewalling

PEM1

PEM2

PEMp

Gi-LAN Option-2 Packet Flow

Wifi and Wireline Model

Service Chaining for Wi-Fi, Broadband & Mobile Networks

Internet,

WiFi

Access

Point

CSS

Residential

Broadband

STB

CPE

ISG

BNG

PCRF/AAA

iWAG

ASR9K(CE)

ASR9K(CE)

TDF

Gx/AAA

NSO/Orchestration

PortalREST

UCS

NED

Netconf/Yang

Elastic Services

Controller

SF1 SF2 SF3

SF1 SF3

BYPASS

Wifi/Wireline Packet Flow

Internet,

WiFi

Access

Point

CSS

Residential

Broadband

STB

CPE

ISG

BNG

PCRF/AAA

iWAG

ASR9K(CE)

ASR9K(CE)

TDF

Gx/AAA

NSO/Orchestration

PortalREST

UCS

NED

Netconf/Yang

Elastic Services

Controller

SF1 SF2 SF3

SF1 SF3

BYPASS

Subscriber Attaches to the network

Subscriber Attaches to the network

Registers with Policy Server

AAA

Service function VMs are spawned

NSO programs TDF and SFs to create

logical service chains

2

1

Service Chains are defined in Portal &

Subscribers are associated with logical

chains

34

TDF obtains subscriber

identification from PCRF/AAA and based on identity tags with

dot1Q and forwards to appropriate chain

6

5

NSO programs TDF and SFs to create

logical service chains

Use Cases: End-to-End Optimization

Background

Common Broadband Access (CBA) Mobile Internet (MI)

Overview of use cases

• FUP (CBA Subscribers)

• If customer is FUP treated the traffic shall be routed via SCE, else bypass SCE

• RAT Type (MI Subscribers)

• If customer is within 2G coverage that traffic shall be routed via the optimizer (aka Mobile Internet Gateway - MIG), else bypass

• Mediation (MI Subscribers)

• For specific destinations (e.g. destinations that are identified as http download) the traffic shall bypass the video optimizer (OWM Integra)

PCRF

SGC

SGC-A

UE

VEM

vSCE NAT

InternetNAT

vSCE Int NAT

vSCE

2

3

4

5

VEM

Option-1:Service Chaining Set-up

PGW/GGSN

WIRESHARK

UpgradePortal

Web Server

Mediation

App Manager

1

FUP Use Case – Before FUP (CBA)

• Subscriber associated with rule CBA_DEFAULT in PCRF

• Subscriber can browse (HTTP/HTTPS), FTP, P2P

• Till they reach their quota limit

• CBA traffic will be steered through SC Green

vSCE NAT

InternetNAT

vSCE Int NAT

vSCE

2

3

4

5

VEMVEM

0

FUP Use Case – During FUP (CBA)• Subscriber quota is exhausted

• Simulated by disassociating subscriber with CBA_DEFAULT and associating with CBA_FUP rule in PCRF

• Subscriber can browse (HTTP/HTTPS)• HTTPS will always be steered through SC

Green

• Non-HTTPS traffic will be steered through SC Red

• FTP, P2P will be blocked• Protocol Fencing (By vSCE)

vSCE NAT

InternetNAT

vSCE Int NAT

vSCE

2

3

4

5

VEMVEM

1

FUP Use Case – During FUP (CBA)

• vSCE send subscriber HTTP 302 Redirect (one-time-redirect) with URL of Quota Upgrade Portal• HTTPS will continue through SP4

• FTP, P2P will be blocked• Protocol Fencing

• Traffic destined to Quota Portal will be steered through SC Blue• Subscriber presented with upgrade option• Subscriber clicks to upgrade quota

vSCE NAT

InternetNAT

vSCE Int NAT

vSCE

2

3

4

5

VEM/ClassifierVEM/Clas

sifier

2

QuotaPortal

FUP Use Case – After FUP (CBA)

• Clicking on “Upgrade Quota” results in changing the subscriber’s state back to CBA_DEFAULT in PCRF

• Subscriber is back on SC Green

• FTP, P2P no longer blocked

• Subscriber can browse (HTTP/HTTPS), FTP, P2P

vSCE NAT

InternetNAT

vSCE Int NAT

vSCE

2

3

4

5

VEMVEM

3

Conclusions Gi-LAN service area is a major pain point today

Not scalable / Hair pining/hard-wired nature limits flexibility / expensive to manage

Cisco Solution

Aligned with ETSI NfV, IETF SFC and SDN techniques

Deployable solution

Engaged mobile operators for POC and use cases deployments

Our direction

Uses SDN & service chaining

Agile and highly scalable

3GPP Policy driven

Cisco Contributions at Various Forums

• Cisco driving industry acceptance and standardization within the IETF

• Service Function Chaining (SFC) working group• http://datatracker.ietf.org/wg/sfc/charter/

• Problem statement, use cases, and architecture WG documents

• NSH gaining wide industry acceptance; many co-authors• http://datatracker.ietf.org/doc/draft-quinn-sfc-nsh/

• Cisco is leading contributor to Openstack Forum

• Cisco is actively engaged with ETSI NFV, 3GPP, Broadband forum etc.

• Various open source engagements; OVS, OpenDaylight

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US Ciscolive 2015 - SP Mobility Sessions

Session ID Time Room No Session Title SpeakersSunday (7 June 2015)

TECSPM-2122 08:00 - 12:00 PM 2 Upper level E2E SPWiFi Solutions Ray Irani, Koh Yamashita

Monday (8 June 2015)

BRKSPM-2122 10:00 - 12:00 PM 25C Upper Level Virtualizing Mobile Service Providers Transport Network Ravi Narahari, Abbas Abidi

BRKSPM-2123 01:00 - 03:00 PM 25C Upper Level Wi-Fi Calling: Supporting voice over carrier Wi-Fi, enterprise Wi-Fi and residential environments Byju Pularikkal

BRKSPM-2125 01:00 - 03:00 PM 24AB Upper level Virtualizing Cisco Mobile Packet Core Mark Ghattas, Dave Clough

BRKSPM-2013 08:00 - 09:30 PM 24AB Upper Level High Density WiFi for Stadiums and Large Public Venues Matt Swartz, Josh Suhr

PLNSPM-2021 01:00 – 02:30 PM 8 Upper Level Under the Top: The Service Provider Advantage Joe Cozzolino, Gee Rittenhouse, Vilma Stoss, Prakash Suthar

Tuesday (9 June 2015)

BRKSPM-2126 01:00 - 03:00 PM 25C Upper Level Analytics for Large Connected Venues: App Integration with Wi-Fi Infrastructure ViswasPuttasubbapa, Matt Swartz

BRKSPM-2021 03:30 - 05:00 PM 24AB Upper Level Service Chaining for Fixed Mobile Networks Prakash Suthar, Ajay Simha

Wednesday (10 Jun 2015)

BRKSPM-2022 08:00 - 09:30 AM 24AB Upper Level Cisco Policy Suite Greg Horkacher, Ben Bleichman

BRKSPM-2023 03:30 – 05:00 PM 25AB Upper Level Cisco Licensed Small Cell Design and Deployment Brian Cox

BRKSPM-2024 01:00 - 02:30 PM 24AB Upper Level Deploying large scale managed SP WiFi Service Ravindra Shankar, Piyus Patel

BRKSPM-2025 03:30 – 05:00 PM 24AB Upper Level Design and Deployment of the ASR5500 Rafael Ceara Batlle, Teru Sato

Thursday (11 June 2015)

BRKSPM-2026 08:00 - 09:30 AM 24AB Upper Level Managing customer Experience for Mobile Networks Anwin Kallumpurth

BRKSPM-2121 01:00 - 02:30 PM 23AB Upper Level Cisco SON Solutions Ashish Bansal, Baljit Singh

BRKSPM-2124 01:00 - 02:30 PM 24AB Upper Level Cisco TelcoCloud and VoLTE Solution Ali Bukhari, Sean Marrow

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