Transcript Document

IMS WorkshopSummary
James Rafferty
August 10. 2006
Agenda
• Recap
–
–
–
–
–
Goals of IMS
Key Elements of Architecture
Applications
Relevance for the Enterprise
Best Practices
• Resources
• Your Takeaways
• Q&A
What is IMS…
• IP Multimedia Subsystem (IMS) is an architecture that
enables wireline, wireless and cable operators to offer
a new generation of rich multimedia services
– Across both circuit switched and packet switched
networking infrastructures
• IMS defines a architecture of logical elements using
SIP for call signaling between network elements
– Provides a layered approach with defined service,
control, and transport planes
The IMS Architecture
IP Multimedia Networks
Legacy mobile
signalling Networks
CS Network
Mm
Mb
Mb
CS
BGCF
I-CSCF
AS
Mm
CS
Mk
Mk
ISC
Mw
Mj
Sh
Cx
C, D,
Gc, Gr
BGCF
Mi
Cx
IMMGW
MGCF
Mc
MRFP
MRFC
Mp
Mb
Mb
Mg
Mr
Mb
Mb
HSS
S-CSCF
Dx
SLF
Mw
Dx
P-CSCF
UE
Gm
Ut
IMS Subsystem
3GPP TS 23.228 V7.2.0 (2005-12)
IMS – Simplified View
Key Elements:
 AS – Application Server
Application
Server
Application
Server
Application
Server
 MRFC - Multimedia
Resource Function
Controller
 MRFP - Multimedia
Resource Function
Processor
SCIM
S-CSCF
HSS/HLR
 MRF – Media Resource
Function
 CSCF- Call Session
Control Function
SIP
I-CSCF
BGCF
P-CSCF
MGCF
MRFC
 SCIM - Service Capability
Interaction Manager
CSCF
 BGCF - Breakout Gateway
Control Function
 MGCF - Media Gateway
Control Function
 MGW - Media Gateway
MRFP
MGW
RTP
MRF
 HSS - Home Subscription
Server
 HLR - Home Location
Register
Other Key IMS Concepts
• Multiple Plane Architecture
– Makes use of separate planes:
• Application, Transport and Session Control
• Common Security and Login functions
– Makes use of Diameter protocol and HSS (Home
Subscriber Server) to validate users
• Applications and Services are independent of
Access Method
– Enables support for 3G mobile, WiFi, DSL, etc.
IMS Benefits
Converged Applications
•
•
•
•
Across Networks
Reduced development costs and time
Voice, Video and data services
Write once / use many
Applications
Video
Hosted
Services
Data
Voice
Win Media
MP3
Web Content
Text
Control
Shared Resources
• Media server resources
• Common user data
• Single user profile across applications
• Integrated applications
SIP
Transport
Session Control
• Common Session Control (SIP)
• Provides common service policies
• Leverages investments across
multiple
applications
Access Network Agnostic
• Eliminates multiple service solutions
• Network transparency
• Consistent services across networks
Access
DSL
CMTS
Mobile
PSTN
Why IMS?
• Need a better environment for creating and deploying
high value multimedia services
• Transform business models from voice-driven to service-driven
businesses
• Fixed-Mobile Convergence on a common IP application and service
delivery architecture
• Grow and protect subscriber base, increase ARPU
(Average Revenue Per User)
• Deliver a differentiated portfolio of value-added services
• Provide more subscriber focused offerings
• Controlling CAPEX and OPEX
• Maturity and adoption of SIP and XML
• Web model development model shortens the required investment of a
programmer to develop new applications
• Enables best-of-breed solutions with focus on new IP application services
• Faster time to market with new services
• Develop on standards-based technology
• Reduce time to market for new applications with web development model
IMS Applications
Unified
Messaging
Announcements
Video Mail
Video
Conferencing
Sponsored
Calling
Pre-Paid
Voice Mail
Conferencing
Video Ringback
Gaming
3G
SIP
IMG
2.5G
SIP
S-CSCF /
SCIM
IP MSC
SIP
MSCML
SIP
VoiceXML
SIP Routing Cloud
Win Media
mp3
IMG
PSTN
MGW
SIP
RTP
SIP
SIP
SIP
w/ VoiceXML
w/ MSCML
HTTP
Web Content
Text
FTP
MRF
Cable CMTS
IP
Phones
(MRFC/MRFP)
MPEG-4
NFS
Network
Storage
Other Likely IMS Applications
• FMC – Fixed Mobile Convergence
• IP Centrex Hosting for Businesses
• Audio and Video combined with other
services
– For example, conferencing, push-to-communicate,
Multimedia over Broadband, Multimedia IM
• Legacy Migration
– Voice mail, conferencing, SMS, Prepaid Services
IMS and the Enterprise
How will IMS affect the Enterprise?
1. IMS will be the preferred hosted services
environment for carriers
2. Enterprises can borrow “best practices”
from IMS for its own services
3. Service orientation of IMS echoes and
complements Enterprise driven
approaches such as SOA (Service
Oriented Architecture)
IMS Best Practices
• IMS includes “lessons learned” from many
predecessor architectures
• Best Practices include:
– Separation of signaling from media
– Separation of Applications from underlying
sessions and transport
– Services provided are independent of underlying
transport
– Common mechanisms for authenticating users
and securing sessions
• Review Call Center Example
Local Campus (Traditional)
Agents on
IP Phones
Customer
Call Center Server
w/ Voip Gateway
Enterprise
LAN
H.323
RTP
T1/E1
ISDN/CAS
PSTN
Agent on
Soft Phone
• All Agents in single location
• Uses all-in-one system to handle all calls
• Signaling and Media combined in one system
Customer
Application of IMS Best Practices
Contact Center Example
• Separate the application server apart from
the Media
• Use a separate Media Resource Function
– Single MRF can support multiple applications
• Use XML + markup languages for fast
development and flexible, mid-call agent
interactions
• Use SIP as the protocol which ties the pieces
together
Case Study:
Distributed Contact Center
Remote
Agent
Application
Server
Agents on
IP Phones
Customer
Media GW
Enterprise
LAN Signaling
Gateway
Internet
RTP
RTP
SIP/
VoiceXML
MSCML
PSTN
MRF
Agent on
Soft Phone
Web
Customer
Email
Customer
Customer
• Improved Scalability: Separate Application from Media
• Ability to add new media such as video as needs evolve
• Fast development using SIP + XML
Resources
• IMS Forum – www.imsforum.org
• 3GPP – www.3GPP.org
• Internet Engineering Task Force –
www.ietf.org
• ETSI TISPAN http://portal.etsi.org/portal_common/home.asp?tbkey1=TISPAN
Workshop
• What our your “Takeaways” from this
course?
• Is there other material you would have
liked to have been covered?
• Any other comments
Q&A