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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
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
• 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
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
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
(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
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
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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