Transcript IMS Overview - Convergence Technology Center

IMS Overview
Vincente D’Ingianni
Director of Professional Services
Binary Systems, Inc.
[email protected]
www.convergencetechnologycenter.org
DUE 402356
Contents
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What is IMS?
Basic Principles
IMS building blocks
IMS Architecture
Why all the excitement?
Who needs IMS
Problems
Conclusions
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What is IMS?
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IMS is an architecture, it is not a protocol.
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Open-systems architecture that supports a range of
IP-based services over both Private and Carrier
networks, employing both wireless and fixed access
technologies.
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IMS is defined by 3GPP.
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Basic Principles
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Access Independence
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Different Network Architectures
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Terminal and user mobility
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Extensive IP-based services
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IMS Building Blocks
1.
An all-IP Core Network (CN)
2.
An all-IP Radio Access network (RAN)
3.
Multimedia call control based on SIP
4.
Quality of Service (QoS) support for IP
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IMS Architecture
Application Layer
SIP / OSA / CAMEL
AS
AS
Management
Control Layer
MRF
SIP, IP
Provisioning
HSS
CSCF
SG/MGCF
Charging
MGW
Connectivity & Access Layer
IP/MPLS
PSTN/PLMN
Number
Mapping
GERAN, UTRAN, WLAN, xDSL,...
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IMS Architecture
HSS: Home Subscriber Server
CSCF: Call Session Control
Function:
SGW
Applications
and Services
Operator 1
I-CSCF: Interrogating CSCF
BGCF
OSA-SCS
BGCF: Breakout Gateway
Control Function
AS: Application Server
CSCF
MRFC: Multimedia Resource
Function Controller
MRFP: Multimedia Resource
Function Processor
MGCF
MGW
AS
SGW
MRFC
SCP
SCP: Service Control Point
MGW: Media Gateway
BGCF
IM-SSF
P-CSCF: Proxy CSCF
MGCF: Media Gateway Control
Function
CSCF
HSS
S-CSCF: Serving CSCF
Multimedia
IP
Networks
Operator 2
MRFP
CS Domain
- or PSTN
- or Legacy
- or External
GGSN
Alternative
Access
Network
Mobile
GERAN
UE
SGSN
UTRAN
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Terminal
Service 3
Service 2
Service 1
Service 3
Service 2
Service 1
Vertical vs. Horizontal Architecture
Common functions
Network
logic
Terminal
Replicated - not reusable
Terminal
Routing
Network
logic
Terminal
Replication of common functions
Application logic
Common functions
Routing
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Why all of the excitement?
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Imagine starting a voice call on you home phone and transferring it
seamlessly to your mobile as you drive to work.
Imagine sending a multimedia message from your car that later
appears on your TV screen.
Imagine watching a movie on that same TV, pausing it in mid-show
and then watching it on a wireless PDA as you relax in the garden.
Imagine having a cell phone conversation with two or three friends
and simultaneously sharing a video of the football match you are
attending.
Imagine that all of the above can be done with a single account, on
a single log-in with multiple devices over any number of access
networks
These are only a few examples of seamless multimedia services
that IMS will allow users to access “anywhere” at “anytime”
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Who needs IMS?
Fixed Network Users want
 Multimedia Conferencing
 Voice over IP
 Streaming Services
Mobile Network Users want
 Push-to-X
 Location Based Services
 Mobile Gaming
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Who needs IMS?
Network Providers want
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Fixed Mobile Convergence
One service - one implementation for all
access types
New Business Models
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An everyday scenario
Vincente
Mobile phone
Daniel
Mobile phone call
In a taxi from the airport...
Gerry
Mobile phone
Mobile phone call
Walking to the office...
Jacqueline
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An everyday scenario
Vincente
Mobile phone
Daniel
Activates Video mode
In a taxi from the airport...
Gerry
Mobile phone
Views Images on his mobile
Walking to the office...
Jacqueline
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An everyday scenario
Mobile phone
Vincente
Daniel
Mobile phone
Buddy list > select project work group
Initiate PTT session
Join PTT session
In a taxi from the airport...
Walking to the office...
Gerry
Jacqueline
Join PTT session
In the office...
Office PC
Join PTT session
In the office...
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Fixed line phone
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An everyday scenario
Vincente
Laptop Computer
Daniel
Mobile phone
Buddy list > personal list
Invite others to Videoconference
Join Videoconference
At the hotel...
Walking to the office...
Gerry
Jacqueline
Join Videoconference
In the office...
Office PC
Join Videoconference
In the office...
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Fixed line phone
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An everyday scenario
Vincente
Laptop Computer
Daniel
Participates in Videoconference
At the hotel...
Participates in Videoconference
Walking to the office...
Gerry
Jacqueline
Opens presentation and shares it
with his colleagues
In the office...
Mobile phone
Office PC
Participates in Videoconference
In the office...
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Fixed line phone
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An everyday scenario
Vincente
Laptop Computer
Daniel
Office PC
Participates in Videoconference
Switches from Mobile to PC
At the hotel...
Arrived in the office...
Gerry
Jacqueline
Participates in Videoconference
In the office...
Office PC
Participates in Videoconference
In the office...
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Fixed line phone
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Problems and open issues
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Architecture complexity.
Guarantees of QoS.
IETF and 3GPP standardisation co-operation.
SIP and IMS architecture are not mature enough
to guarantee fully functioning network.
Terminal complexity.
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There is still work to be done....
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The current work in 3GPP is still unfinished and
the discussion with IETF has just been started.
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The specification work still continue now.
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Selected Acronyms
3G
Third Generation
3GPP(2) Third Generation Partnership
Project (2)
API
Application Programming Interface
AS
Application Server
BGCF
Breakout Gateway Control
Function
CAMEL Customised Applications for
Mobile Enhanced Logic
CSCF
Call Session Control Function
BICN
Bearer Independent Core Network
GGSN
Gateway GPRS Support Node
GPRS
General Packet Radio Service
GSM
Global System for Mobility
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IMS
IP
IP-CAN
ISIM
IWF
LAN
QoS
RACS
RAN
SCM
SGSN
SIP
SLA
UMTS
IP Multimedia Subsystem
Internet Protocol
IP- Connectivity Access Network
IMS Subscriber Identity Module
Inter-Working Function
Local Area Network
Quality of Service
Resource and Admission Control
Subsystem
Radio Access Network
Session Control Manager
Serving GPRS Support Node
Session Initiation Protocol
Service Level Agreement
Universal Mobile Terrestrial
Access
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