Implementing Cellular to Wi-Fi Offload

8/9/2019 Implementing Cellular to Wi-Fi Offload

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SOLUTIONS FOR IMPLEMENTINGCELLULAR TO WI-FI OFFLOAD Hartmut Schroeder

September 2012


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2 Copyright © 2012 Juniper Networks, Inc. www.juniper.net

Legal Statement

Statements of direction set forth Juniper Networks’ current

intention and are subject to change at any time without notice.

No purchases are contingent upon Juniper Networks

delivering any feature or functionality depicted in this presentation.


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WHY WI-FI OFFLOAD?


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GROWTH IN WIRELESS BROADBAND DATA CONTINUES

Growth fueled by:• Increased Smartphone Adoption• Wireless Enabled Portable Devices• Machine-to-Machine Mobile DevicesGartner predicted that tablet sales will grow 181% in2011 to 54.8M, many of which are built to takeadvantage of mobile 3G and 4G networks.

According to IDC we will reach 1 billion smart mdevices in 2013. Morgan Stanley tells us we will mobile devices in 2050.

181% TABLETGROWTH

1B SMART MOBILE

DEVICES

http://www.gartner.com/it/page.jsp?id=1452614http://www.gartner.com/it/page.jsp?id=1452614


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WIRELESS BROADBAND ALLIANCE


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6Copyright © 2012 Juniper Networks, Inc. www.juniper.net

3 STAGES OF WI-FI OFFLOAD

Offload•Hard offload•User driven•Unmanaged

Optimize• Auto-login•User identity•Secure

Integrate•Policy d•Session •Fully tra

Source: Heavy Reading2010 2012 20


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REFERENCE ARCHITECTURE


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KEY SOLUTION COMPONENTS

AUTHENTICATION& SECURITY

BACKHAUL & EDGE POLICY ENFO& CHA

• Security GW• Video/Web

Optimization• NAT/FW functions• Server Load

Balancing• Mobility GW functions• Routing Functions• VPN Gateway

Provides uniform userexperience with authentication,security & policy enforcement

Provides secure traffictermination and service

delivery functions

Provides suppobased policy en

cha

MX-3DJUNOS Pulse Client (optional)• Mobile Security Suite• VPN / secure tunneling• Enforcement point for future policy

based capabilities and datacollection

SBR – CARRIER• Single platform managing AAA

functions for all accesstechnologies

• High performance• Reliable mobility• High Availability• Outdoor/Indoor• Superior Planning

and Lifecycle Mgnt• Direct and Central

Traffic breakout

Juniper WLAN • Ideal if WLAN traff

GGSN / P-GW• Leverages Juniper M

• QoS• Service M• DPI

• Captive Portal• Volume Tracking (V

• Bandwidt• Daily/Mo

• Charging integration


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OPEN AND SECURE ACCESSE2E ARCHITECTURE PHASE 1 (TODAY)

WLM

Open

802.1x

WLC AP

SBR SRC

Portal

SSR VTA Auth-Check /Service

Subs-DataBase / HLR

Policy push

MX-BNG

Smartphone

Policy push RedirectIP

TaRad

JSRCDia

GiIP

Corba

SQLSIGTRAN


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Juniper MX as Wi-Fi AccessGateway acts as a PCEF for

CGNAT (leveraging MS-DPC)DPI (leveraging MS-DPC)Basic QoS / Hirachical QoS(leveraging MS-DPC)Lawfull Interception Point for CCDHCP-Server

SBR Carrier AAA with SSRSIM-Module for seemlessauthentiaction with HLR for EAP-SIM/AKASession State Register for global,redundant Subscriber Knowledge

Juniper SRC (Session ResoController)

Captive PortalVolume Tracking ApplicaVarious Accounting InterPolicy push to all Junipe

Juniper Wireless WLA / W

WLM Wi-Fi Access with BackhCentral SwitchingComplete Livecycle Manthrough RingMaster

JUNIPER VALUE PROPOSITION


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UNIVERSAL EDGE


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MX 3D: A NETWORK SERVICES PLATFORM

Ultimate inVersatility

ensures themade for evmodelL2 to L3 toSupport musimultaneoimpacting p

Industry-leading performance andscale

OPEX SavingsSimplifies operations

30 – 50% more power efficient & 40% more space efficientEmbedded monitoring services to ensure SLAs are metUnparalleled functional bundling that allows massive cost saving

Unparalleled packetprocessing performanceSeparate control and dataplane that scaleindependently


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Services Flexibility for MobileMX 3D with Trio is a Common Services Layer for IP Convergence

Comm on hardware , com mo n sof tware, inves tment p ro tec t ion

MX 3D

TWAGSecurity-GW

S/P-GW

Backbone

Backhaul

Carrier Gra

BN

Firew

Business GGSN

Packet Core

Transport

Fixed E

Secur

DatacL2/L3 S

SDG


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Networ

Se

Network-Integrated Apps.

& Services (Juniper )

UNIVERSAL EDGE ENABLES NEW NETWORK

Router-Integrated Servi

Cable EdgeBusiness Edge

Mobile EdgeCarrier Ethernet AggregationVideo Distribution Networks DAABGF Media Flow

TelchemePM

IPS

Media FlowController

SRCController

MX 3D Series

Network Applications


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JUNIPER WIRELESS


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THE NONSTOP WIRELESS NETWORK

Single point of management

Active-active controlarchitecture

Self-organizing adds, movesand changes

Self-repairing architectureIn service software upgrades

Full Featured Local switching


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JUNIPER WLA SERIES ACCESS POINT FAMILY

Entry level 802.11n Indoor 11n Outdoo

Single Radio

Low Cost AP

WLA321

Dual RadioEntry-level AP

WLA322

2x2 MIMODual Radio

High Density

WLA522

WLA Series Highlights

Highest performance APs in the industryMost cost effective APs in the industryFull featured Intelligent switchingSpectrum analysis across the portfolioBridging and mesh

3 StreamMIMO

Dual RadioMax.

Performance

WLA532

F u n c

t i o n a

l i t y

3x3 MIDual RaAll Weat

WLA6

WLA532

New

New


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JUNIPER WLC SERIES CONTROLLER FAMILY

WLC Series Highlights

Simplest solution in the Industry Highest Reliability in the industry Only vendor with In-service upgrades One software platform

Full Featured distributed deployment

4 12 16 32 128 192 2564

4 AP

WLC2WLC8

12 AP

16 - 128 11n AP 3-Stream

WLC800

B r a n c

h

C a m p u s

E n

t e r p r i s e

16 - 256 11n AP 3-Stream

WLC880

64 - 512 11n A

WLC280


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SBR CARRIER


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SBR CARRIER: ENABLES SEAMLESS ACCESS

Steel Belted Radius

Seamless integration:Supports any SDMtechnology with any

schema

Reduce operationalcost: Single platformmanaging AAA

functions for allaccess technologies

Reduce compleSingle platformglue between ne

technologies ansystems

GPRS UMTSHSxPA

xDSLFTTH

UMAFemtocell

Public Wi-Fi

Fixed/MobileWiMAX

HLR RADIUSLDAP SQL

FLEXIBLE SDM INTEGRATION: ANY


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FLEXIBLE SDM INTEGRATION: ANYCREDENTIAL, ANY DATABASE

Steel Belted Radius

HLR LDAP SQL

HLR authenticationD’ authentication andauthorization InterfaceSIM and AKASS7 over E1/T1

SIGTRANMAP v2/v3NO separate MAP-GW(installed on SBR)

ORACLE

LDAPLDAP v2/v3Load-balancing andfailover

Any LDAP schema

Programmable searcheswith recursivenessScriptingUnparalleled performance

SQLGeneric SQL over JDBCLoad-balancing andfailover

Any SQL schemaStored procedure support

OracleNative oracle interfaceLoad-balancing andfailover

Any SQL schema

Stored procedure supportUnparalled performance

CredentialsUsername/CertificateSIM & USISMS OTPTokenService-ID


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JUNIPER SRC

SRC ENABLES


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SRC ENABLESAPPLICATION INTELLIGENT NETWORKING

N e

t w o r k

P o

l i c y a n

d C o n

t r o

l

S e r v

i c e

InternetIPTVHome VoIP

CoreEdge

Service Activation / Repo

Provisioning / Accou

ApplicationsResidentialServices

SRCPolicyEngine

C3000

Dynamic ProvisioningFilters, Captive Portal, Bandwidth,…

Resource ControlCall Admission control, QoS ,…

Metering

Per service time & volumeQuota services


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SRC USAGE TRACKING / ACCOUNTING OPTIONS

End user

Policy

SRCSubscriber

state & profile

Traffic

Flat fileRADIUS

Custom Plug-in

VTA

VTA Plug-in P l u g - i n

A P I

MX

WLC 2800Wi-Fi AP


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ENHANCED SUBSCRIBER MANAGEMENT

Per subscriber accounting

Regular EnhancedPer Service Acco

Benefits:• Usage based billing

• Congestion mitigation by de-prioritizing heavy users

Features

• Periodical collection of counters associated to SRC managed services

• Based on combination of 5-tuples or per application/application-groups

• Accounting record generation from SRC (flat files or RADIUS) – duration and volumes

• Multiple accounting sessions per subscriber

• Start, Stop and variable Interim

• Fair usage / quota services with Volume Tracking Application


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OVERVIEW OF THE SRC VOLUME TRACKING APPLICATION

The SRC Volume-Tracking Application (SRC VTA) allows serviceproviders to track and control the network usage of subscribers andservices. You can control volume and time usage on a per-subscriberor per-service basis.When a subscriber or service exceeds bandwidth limits (or quotas), theSRC VTA can take actions , including

directing the subscriber to a portal to activate additional services orpurchase additional bandwidth,imposing rate limits on traffic,sending an e-mail notification,or charging extra for additional bandwidth consumed.


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FUTURE PRODUCTS /SOLUTIONS


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HOTSPOT V2.0


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IEEE 802.11U AND HOTSPOT V2.0 PART 1IEEE 802.11u (Standardization finished Feb 2011)

Allows a Station (UE/Mobile) to query information about the WLAN and Network behind it Authentication is triedMust be supported at WLAN-AP and UE/Mobile to work

Network Discovery and Selection component Advertise Networks basic 11u capabilities in Beacons and Probe Response Frames to minimize Battery impact

– Access Type – Venue Info – HESSID – supported Advertisement Protocols – Roaming Consortium – Emergency Call ongoing Alert

Generic Advertisement Service (GAS) for extended Queries – Access Network Query Protocol ( ANQP ) and others (MIH)

QOS Map Set distributionTell the Mobile which QOS DSCP Marking to set for IP Traffic according to operators policyExpedited Bandwidth Request (EBR) support

Emergency servicesEmergency Call and Network Alert support at the link level


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IEEE 802.11U AND HOTSPOT V2.0 PART 2

Hotspot V2.0 GoalsImprove end-user experience to level of cellular networksFacilitate Wi-Fi offloadFacilitate Wi-Fi roaming agreements between hot spot operators/service providers

DeliverablesTechnical Spec. (uses heavily 11u), Test Plan, Certification Program , Deployment Guide

Phase 1 (called “Passport”), Certification starts: mid-year 2012 – Access network discovery

– Security

Phase 2, Certification starts: mid-year 2013 – Operator Policy (TBD) Will it be ANDSF? At which Sublevel then?

– On-line Signup (TBD)

Phase 3, Certification starts: TBD probably mid-year 2014 – Scope isn’t defined – proposals have been made around Wi-Fi offload issues and improved operations/monitoring.


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IEEE 802.11U AND HOTSPOT V2.0 PART 3Network Discovery (Phase 1)

New information elements (11u based)Interworking, Advertisement Protocol, Roaming Consortium, BSS Load, WFA Peer to Peer

GAS/ANQP Protocols (11u based)

ANQP: Venue Name, Network Authentication Type, IP Address Type Availability, Network Access Identifier RealList, 3GPPP MCC/MNC, Domain Name ListHS2.0 ANQP extensions: Operator Name, WAN Metrics, Connection Capability, NAI Home Realm Query

Note: Only a SUBSET of 11u will be certified in HS 2.0. – QoS-Mapping Tests and Emergency Calls are not scope of HS2.0

Security (and Battery Life Extension) (Phase 1)Certification includes 802.1x based WPA(2) Enterprise Authentication

EAP-TLS, EAP-TTLS (inner MS-CHAPv2), EAP-SIM/AKA ( if the Device has a (U)SIM-Card it SHALL Certification does NOT include UE based Tunnels

Hotspot V2.0 certifies “sort -of” 3GPP “Trusted Access” Mobiles / UE’s only Proxy ARP and Proxy Neighbor Discovery (802.11v)Downstream Group Addressed Frame ForwardingPeer to Peer Communication Blocking


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3GPP TRUSTED ACCESS

( )


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WI-FI OFFLOAD USING S2A GTP (SAMOG)

Smartphone

Secure Simplified Access for Trusted Wi-Fi Networks

WLANAccess

AP

Backhaul &Packet Core Service

Complex

VPN

SDGPGWGGSN

HA

Policy and Credential SNe A ANDSF

CredentialMngt

SaMOG GW

GTP S2a

• Documented in TS 23.402 section 16 for 3GPP Rel 11• 802.1x recommended to ensure air interface security (WPA)• EAP-AKA credentials used to authenticate the UE

• Needed to get IMSI identity of the UE• Allows HSS to pass information required for GTP management (including

target PGW)• Needed for IP future address preservation

• Leverages standard GTP “Create/Modify” Session/Bearer messages

HSS/AAA

BENEFITS:• Avoids cost and overhea• Uses standard GTP base

CAVEATS:• Used only for trusted W• TWAG must see UE-M• IP-Address preservation

TRUSTED WLAN ACCESS TO EVOLVED PACKET COREARCHITECTURE


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ARCHITECTURENo additional SW on UE / IP address Preservation (and no IKEv2/IPsec/ePDG)SWw is a point-to-point IP link over 802.11 protected by 802.1X

Access Control enforced by Trusted WLAN on behalf of 3GPP operator (802.1X)Default APN for Trusted WLAN PDN connection stored in subscription data

hPCRF

HSS

TrustedWLAN Access

Network

PDN Gateway HPLMN

Non - 3GPPNetworks

VPLMN

vPCRF

S2a

S9

SGi Gx

S6b

Operator's IPS ervices

(e.g. IMS, PSSetc.)

Rx SWx

Gxc

S8

S6a

3GPP Access

Serving Gateway

SWw UE

S2a Mobility based On GTP andWLAN access to EPC (SaMOG)

TRUSTED WLAN ACCESSINTERNAL FUNCTIONS


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INTERNAL FUNCTIONS

WLAN: APs terminating UE’s SWw 802.11 WLAN link Authenticates UE with EAP-AKAProvide integrity and/or confidentiality protection

Trusted WLAN Access Gateway ( TWAG ):Creates/Deletes S2a GTP tunnelDefault router and DHCP serverEnforces packet forwarding between UE’s SWw point-to-point IP linkGTP tunnel based on UE MAC address

Trusted WLAN AAA Proxy ( TWAP ): AAA proxy b/w WLAN Access Network and 3GPP AAA Server/Proxy overBinds UE subscription data (e.g. IMSI, APN ) with UE MAC addressNotifies TWAG of UE L2 Attach to / Detach from WLAN

SWw

Intranet / Internet

Trusted WLAN Access Network

WLAN

Trusted WLP

Trusted Access G

TRUSTED WLAN ACCESSPDN & NSWO POINT TO POINT LINK MODEL


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PDN & NSWO POINT-TO-POINT LINK MODEL

S2a PDN Connectio

802.11Bridging

DL: TWAG unicast to UE MAC

UE MAC

S2a-TEID or NSWO

TWAG PDN G AP/WLC

NSWOa.k.a. LocalBreak-Out

PDN1

UL: AP/WLC force-forwards

802.11 Association Per PDN/NSWO

VLAN orGRE tunnel

UE1

UE2

UE3

UE4

TRUSTED WLAN ACCESSINITIAL ATTACH


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INITIAL ATTACH Roaming Scenarios

UE AAAProxy

PDNGW

3. Create Session Request

TWAN

2. Authentication & Authorization

5. Update PDN GW Address

2. EAP Authentication

1. Non-3GPPSpecific Procedures

15. L3 Attach Completion

7. GTP Tunnel

6. Create Session Response

4. IP-CAN Session EstablishmentProcedure

vPCRF

9. L3 Attach

8. EAP authenticationCompletion

10. Create Session Request

12. Update PDN GW Address

14. GTP Tunnel

13. Create Session Response

11. IP-CAN Session EstablishmentProcedure

Two variants based on PDN: A. IPv4, IPv6, IPv4v6,

based on successfulauthentication event(recommended)

B. IPv4 only,based on DHCPv4address request

High Level SaMOG Call Flow


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4 Way Handshake

Diameter EAP Response

EAP Response from UE to WLC

EAP Response from UE to WLC

High Level SaMOG Call Flow

RADIUS EAP Response

(MAC, VLAN)

SaMOGGateway

IEEE 802.11Discovery

AAAWLANController

AccessPoint

UserEquipment

Layer3 VPN

Diameter EAP Success

GTP Request Response

Acquired IP Address

RADIUS EAP SuccessEAP Success to UE

Derive PTK Derive PTK

Ready to use / OK to use

IEEE 802.11 AES Data EncryptionDHCP Request / Response

8 02.1 1 ab g 802.11 in CAPWAP (VL AN, M AC ) IP Packet

EAP Request to UE

Diameter EAP RequestRADIUS EAP RequestEAP Request to UE

Diameter EAP Response

T

GTP-Traffic

TRUSTED WLAN ACCESS TO EVOLVED PACKET COREMOTIVATION PHASE 2 / REL 12


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MOTIVATION – PHASE 2 / REL-12

Desire for (missing) Additional FunctionsIP address preservation across handovers b/w 3GPP and WLANConcurrent Connectivity

Multiple PDN connectionsConcurrent 3GPP access & Trusted WLAN AccessConcurrent PDN Connectivity and Non- S eamless WLAN Offload

UE / NW Selection of APN & NSWO

Solution Space has 2 dimensions:UE / NW Signalling for APN/NSWO & attach/handover/detach

Layer 2: extensions to EAP-AKA or 802.11 ANQPLayer 3: extensions to DHCP/DHCPv6

Per-PDN / NSWO Link ModelPer-PDN/NSWO VLAN taggingPer-PDN/NSWO MAC address on TWAG side

TRUSTED ACCESS VISION TOWARDS FMC


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TRUSTED ACCESS VISION TOWARDS FMC

2G/3G RAN

GGSN

SaMOG basedTWAG

AAA

NetwSGSN

HLR

Gn (GTP)

OCS

Non HLRbased SDM

Trusted AccessEAP-SIM/AKA

Trusted AccessEAP-TTLS

BRAS

Any AccessNetwork

Set-TopDHCP

CPEPPPoX

Interne


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JUNOS PULSE WI-FI MANAGER MODU

WHY USE CLIENT TECHNOLOGYFOR WI-FI OFFLOAD?


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FOR WI-FI OFFLOAD?

Does OS natively provide tunneli

If the answer to ANY question is “no”, then a client is required!

Does OS support selective tunnel& confidentiality?

Does OS support policy-basedcontrol of network selection andapplication routing?

Does OS support management ofmore than just Wi-Fi authenticaticredentials? 3 rd party roaming

End User Quality of Experience


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Q y p

Wi-Fi Offloading can help.However….

Solution must be 100% seamless andtransparent to the end user

Completely automatedZero end user interventionNo compromise on quality of connectionNo compromise on device performance

EL

Junos Pulse & Wi-Fi Offload


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End User/Device(UE)

Th

Enhances end userQuality of Experience

Junos Pulse + Pulse Wi-Fi Managerbridges the gap between thenetwork and the end device

Significantly enhancing end thequality of experience (QoE) whilestill offering control to the carrier or

enterprise

Pulse manages 3G/Wi-Finteractions based on prdefined policy

Junos Pulse

PULSE WI-FI MANAGER ANDROID SUPPORT ONLY IN PHA


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Manage Wi-Fi

Wi-Fi Provisioning- Push & manage Wi-Fi profiles- Use on-device supplicant

Location & Device Aware- User location (city level)- Device type (iOS/Android)- e.g. User in Austin provisioned withSSID A & SSID B, User in San Joseprovisioned for SSID A only

Automatic credentialmanagement- Addresses gap for non EAP-SIM/AKA enabled Androiddevices

Smart Wi-Fi On/Off

Turn Wi-Fi On/Off on the devicebased on location

- Balance UX with Wi-Fi attach- Automate action or notify user

- e.g. Enable/Disable Wi-Fi based onproximity to malls, stadiums etcbased on “3G Cell broadcast ID”information

App Notification

Discourage Offload for walledgarden applications

e.g. Notify user and allow them toswitch to 3G/4G when they runcertain walled gardened applications.

VPN

Setup VPN tunnel fron Wi-Fi type etc.

- Secure air link- Enable Wall gardenbackhaul- No IKEv2 (SSL VP*Scale factors must b

Rep

Measure ROI &- Bytes offloaded o- Time spent on W- Apps used, type- By SSID, AP, L


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Pulse Wi-Fi Offload including Trusted Access


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BTS SGSN

HLR

RNC GGSN

Wi-Fi AP802.1x SSID

Pulse Wi-FiManager (PWM)

Firewall

Junos Pulse

Phone bootsup. Pulse

starts runningon the device

Pulse collectsIMSI + MSISDNand contacts Wi-Fi Manager over3G/4G networkto get policies

Policy gets downloaded

to device over 3G/4Gnetwork. Policy includesWi-Fi profiles,credentials, location,application & othercriteria etc.

Pulse takesaction on devicebased on Policy

User connects to Wi-Fibased on Policy. Policycontrols when & how

user is offloaded.

Trusted Wi-Fi Access Gatew(SaMOG) forwards Layer 2Traffic into GTP towards GG

g

Use 802.1x Authenticationwith the AAA based onPEAP or EAP-TTLS

T-WAGSaMOG


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PROVIDER ROAMING & WHOLESALE

EAP-IDENTITY BASED ROAMING EXAMPLE (W. CLEARING H


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Smartphone

User

Wi-Fi AP

InternetSubscriber DBor HLR

SubscribersHome AAA

MetroNe

WLC 280

Clearing House AAA

1.) Subscriber moves to a Visited Network and attaches to next Wi-Fi AP.2.) AP directs all Traffics through Metro (or Internet) to Wi-Fi Controller at Visited Network3.) Wi-Fi Controller notice a new attachment and asks the UE for the EAP-Identity to start the EAP negotiation4.) UE answers and starts EAP-Exchange with EAP-Identifier

5.) Wi-Fi Controller creates Radius Request to local (Visited) AAA6.) Realm Part of User NAI identifies request can’t be authenticated local -> Proxy forward to Clearing House AAA7.) Clearing House AAA identifies Home AAA and forwards request.8.) Home AAA analyses request (he may answer with a challenge which will case a few more interactions back andforth before he can make a final conclusion)9.) Home AAA authenticates Subscriber on Database/HLR and sends back Access-Accept (with a Profile to be used)10.) Answer get’s routed back the same way to VAAA (which analyses the Profile setting and may override it)11.) Wi- Fi Controller get’s Access -Accept with negotiated Cryptographic Keys and starts the $-Way Handshake withthe UE to secure the Air interface (AES-CCMP)12.) Wi-Fi Controller generates Radius Accounting Information to be forwarded (VAAA to HAAA via Clearing House)

EXAMPLE ROAMING - VPLS BASED


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HAAA

H-HLR/HSS

PulseManager

VPLS basedRoaming

WAG

VAAAProxy

SWdHome NetworkVisited Network

VAAA to add VLANattribute per Home

Network on returnedAccess-Accept

WLAN AP

WLAN AP

WLAN WLC

MAC / VLAN

ROAMING TRUSTED LOCAL SAMOG


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H-GGSNH-PGW

HAAA

H-HLR/HSS

PulseManager

OCS

Gp/GTP basedGRX roaming

Visited WiFiAccess Gateway

(SaMOG)

VAAAProxy

SWd

Home NetworkVisited Network

WLAN AP

WLAN AP

WLAN WLC MAC / L2

ROAMING TRUSTED HOME SAMOG VPLS


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H-GGSNH-PGW

HAAA

H-HLR/HSS

PulseManager

OCS

VPLS basedRoaming

Home WiFiAccess Gateway

(SaMOG)

VAAAProxy

SWdHome NetworkVisited Network

VAAA to add VLANattribute per Home

Network on returnedAccess-Accept

WLAN AP

WLAN AP

WLAN WLC

MAC / VLAN

Implementing Cellular to Wi-Fi Offload

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