Services in UMTS Networks

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Services in UMTS Networks

• per.johansson_at_ericsson.com

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Outline

• UMTS Architecture Overview
• GPRS Mobility and Roaming
• GPRS QoS
• IP Multimedia Subsystem
• Home Network Environment
• Open Service Access -- OSA
• Relation to ISP structure

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UMTS Architecture Overview

• An implementation of the IMT-2000 requirements
• WCDMA radio access
• Higher rates and QoS
• Major effort Provide Internet oriented services!
• SIP based multimedia support
• Open interfaces
• Modular approach
• Allows for independently evolving network
  components
• Physical entities grouped into Domains
• Grouping of protocols offer services in Strata
• Provided by one or several domains

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UMTS Architecture - (Physical) Domains
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Network Stratawhats that?

• A (telecom?) way to abstract the notion networks
  of networks
• Stratified Reference Model -- SRM

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Example
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IP
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Network Stratum n-1
Network Stratum n-2
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ATM VP/VC
Network n connectivity
Network Stratum n
SONET/SDH
Link functions
Infrastructure n
Etc...
DWDM
Network n
Network n-1
Network n-2
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Strata -- Functional Aspects of UMTS
Stratum Grouping of protocol layers providing a
specific service
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Application Stratum

• Applications provided to the end user
• Applications may be within or outside the scope
  of UMTS
• PS and CS based applications

Note!
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Packet Switched and Circuit Switched Domains

• One PLMN (Public Land Mobile Network) is One
  Mobile Operator
• Migration from GSM to UMTS crucial
• Coexistence over long period foreseen
• Multimode mobile equipment

PDN (e.g. IP Network)
GSM BSS
PS Domain
Home Domain
Core Network
ME
CS Domain
PSTN
UMTS RNS (UTRAN)
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In more detail...
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GPRS -- Generic Packet Radio Service

• Introduces Packet Switching to Cellular Networks
  -- the 3GPP way!
• Concept Hide cellular specifics from the legacy
  PS (PDN) domain
• Migrate from GSM to UMTS access with the same
  GPRS Core Network
• Use legacy PDN as infrastructure for the CN
• Many design decisions made pre-Internet boom --
  IP not given!

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GPRS user plane for GSM and UMTS access
GSM
UMTS
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GPRS Mobility
GTP Tunnels redirect traffic!
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GPRS Roaming two alternative ways
Home Services

• ISP Roaming
• Visited GGSN the network access
• Services Internet based
• Gives more optimal routing
• No static IP addresses
• PLMN Roaming
• Home GGSN the network access
• Operator based services.
• Collection of charging data in home PLMN
• Additional screening in Home GGSN
• Access to all services and networks that are
  available in the Home network
• Needs Inter-PLMN GPRS Backbone Network for GTP
  tunnels

ISP
ISP
Home Services
Local Services
ME PLMN B
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PLMN Roaming GPRS Roaming eXchange -- GRX

• Provides secure and QoS based (VPN) operator
  roaming (GTP tunneling)
• .gprs root DNS services
• BGP-4 routing (PLMNAS)
• Support for peering p2p Roaming Agreements still
  needed.

PLMN1 (Home)
BG
DNS
R
GRX
PLMN2 (Visited)
PLMN3
R
R
BG
BG
DNS
DNS
ME PLMN 1
SGSN
SGSN
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Roaming Brokering

• Centralized handling of roaming relations
• Broker acts as full HPLMN and VPLMN w.r.t.
  contractual relationship.
• Peered roaming big hurdle for new operators
• Claim Enables 3G roaming to scale
• Claim Brokering enables fast time-to-market
• Example Comfone/Infonet gt GRX on IPoATM
  backbone, Roaming Agreement support services,
  Roaming Brokering

PLMN1 (Home)
BG
DNS
Roaming Agreement
SLA
R
GRX
PLMN2 (Visited)
PLMN3
R
R
BG
BG
DNS
DNS
ME PLMN 1
SLA
SLA
Roaming Broker
Roaming Agreement
Roaming Agreement
SGSN
SGSN
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Global GRX network

• Next level of peering GRX-GRX
• Biggest peering point AMS-IX
• Now 17 GRXes Aicent, Belgacom, Cable Wireless,
  Carrier1, Comfone/Infonet, Deutsche Telekom,
  Ebone, Energis, France Telecom, Global Crossing,
  KPNQwest, Sonera/Equant, Telecom Italia, Telenor,
  Telia, Telecommunications Services Inc, WorldCom

Operator C
BG
DNS
GPRS Peering Network
SGSN
GRX
R
DNS .gprs
R
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UMTS QoS Architecture

• End-to-End approach

External IP QoS (e.g. RSVP/Diffserv)
UMTS QoS
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IP vs. UMTS QoS

• Policy Enforcement Point
• Diffserv edge function
• RSVP sender/receiver proxy
• Mapping between IP and UMTS bearer QoS
• UMTS QoS classes
• Conversational class
• Streaming class
• Interactive class
• Background

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IP Multimedia (IM) Domain

• Support for real time multimedia services
• Combined support from PS and CS bearer services

IM Domain
PDN (e.g. IP Network)
GSM BSS
PS Domain
Home Domain
Core Network
ME
CS Domain
PSTN
UMTS RNS (UTRAN)
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IP Multimedia Subsystem

• SIP based signaling
• Separate overlay network for MM support

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UMTS Virtual Home Environment

• Provides portability for the Personal Service
  Environment
• Users presented with same personalized features
  regardless of network and terminal
• VHE components
• User Profile
• Generic QoS bearer services
• Call control (e.g. IMS)
• Service Toolkits
• CAMEL (IN in GSM)
• OSA (API for 3rd party service development)

CAMEL Customized Application for Mobile Network
Enhamced Logic
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User Profile(s)

• The user profile aspects
• Classification (personal and service specific)
• Location and distribution
• Mgmt and access
• Policies
• Synchronization
• Security and privacy
• Format

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3G Operators Export Products

• What have 3G operators to offer Service
  Providers?
• 3rd party involvement of Internet based service
  providers seen as essential for growth

• Offered
• Large customer base!
• IP connectivity
• Controlled QoS (MM apps etc.)
• User location (geographic, network)
• Global Mobility and Roaming
• VHE
• Security
• Application based charging
• VPN access

Service Application providers
Basic Services
Core Network
RAN
Internet
MS
GPRS

• In return
• Reach internet content
• Shared risks
• Faster application development
• Reach customers via other ISPs (accesses)

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How to export the 3G functionality package?

• The IN way too expensive...
• Compare number of SS7 developers with Java/HTML
  developers!
• IP transport and open interfaces enables
• Shared computing platforms for telecom and
  Internet applications
• Shared (IP) infrastructure
• Integration of IDCs and telecom hotels (Note!
  Still Carrier Class performance and availability)
• Globally distributed Home servers
• gt Expected to give fast and cheap development
  for 3G applications!

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OSA - Open Service Access

• Part of the Virtual Home Environment
• Open, standardized API for 3rd party application
  developers
• Developed in the Parlay group
• Exports typical Mobile Network Functionality
• Call control, UMTS QoS
• User location, Terminal capabilities
• Content based charging

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OSA - Open Service Access

• Applications
• VPN
• Conferencing
• Location based applications
• .

• Framework mechanisms
• Authentication
• Discovery of service capabily features

• Network Service Capability Features
• (Abstractions of network functionality)
• Call control
• User location
• Terminal capabilities
• Charging

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OSA and Server distribution

• Actual servers and the SCS may be distributed
• Optional to run on the same physical server or in
  one or more separate
• Implications for application server placement in
  the network?

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So does all this fit into an Internet Service
Architecture?
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ISP structure -- MO must adapt to this...
customer (e.g., corp.)
regional ISP
customer (e.g., corp.)
customer (e.g., corp.)
IX
regional ISP
regional ISP
backbone provider
access network
backbone provider
IX
backbone provider
IX
regional ISP
link
access network
access network
BGP-relation
customer (e.g., corp.)
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ISPs, data centers, and perimeter protection
IX
backbone provider
backbone provider
e.g., modem pool or CATV
access operator
backbone provider
IX
link
BGP-relation
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GPRS operators -- MO needs to adapt to this
GPRS operator
PS CN
IX
backbone provider
backbone provider
e.g., modem pool or CATV
access operator
backbone provider
IX
GPRS operator
service/ content
GPRS operator
link
The NO
PS CN
BGP-relation
PS CN
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GRX, a separate unsecure IP structure
GPRS operator
PS CN
IX
GRX
backbone provider
backbone provider
e.g., modem pool or CATV
access operator
backbone provider
IX
GRX
GPRS operator
service/ content
GPRS operator
link
The NO
PS CN
BGP-relation
PS CN
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IMS...
GPRS operator
IMS
PS CN
inter-op. IMS
IX
GRX
backbone provider
backbone provider
e.g., modem pool or CATV
access operator
backbone provider
IX
GRX
inter-op. IMS
GPRS operator
service/ content
GPRS operator
link
IMS
IMS
The NO
PS CN
BGP-relation
PS CN
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Issues

• Performance implications on GTP tunneling and IMS
  backbone VPNs?
• Will application developers buy into the OSA
  idea?
• How easy will it be for current SPs to offer
  applications to mobile customers?
• Can OSA be easily distributed?
• Alternatives?
• Direct Internet access from mobiles
• Service adaptation in overlay networks
• Mobile IP?
• Specialized Radio QoS overlay support network?