IP Multimedia
Subsystem (IMS) is a generic architecture for offering
multimedia and voice over IP services, defined by 3rd Generation
Partnership Project (3GPP). IMS is access independant as it supports
multiple access types including GSM,
WCDMA, CDMA2000, WLAN, Wireline
broadband and other packet data applications. IMS will make Internet
technologies, such as web browsing, e-mail, instant messaging and video
conferencing available to everyone from any location. It is also
intended to allow operators to introduce new services, such as web
browsing, WAP and MMS, at the top level of their packet-switched
networks
IP Multimedia Subsystem is
standardized reference architecture. IMS consists of session control,
connection control and an applications services framework along with
subscriber and services data. It enables new converged voice and data
services, while allowing for the interoperability of these converged
services between internet and cellular subscribers. IMS uses open
standard IP protocols, defined by the IETF. So users will be able to
execute all their services when roaming as well as from their home
networks. So, a multimedia session between two IMS users, between an
IMS user and a user on the Internet, and between two users on the
Internet is established using exactly the same protocol. Moreover, the
interfaces for service developers are also based on IP protocols.
Some of the possible
applications where IMS can be used are:
-
Presence services
-
Full Duplex Video
Telephony
-
Instant messaging
-
Unified messaging
-
Multimedia advertising
-
Multiparty gaming
-
Videostreaming
-
Web/Audio/Video
Conferencing
-
Push-to services, such
as push-to-talk, push-to-view, push-to-video
Effectively, IMS provides
a unified architecture that supports a wide range of IP-based services
over both packet- and circuit-switched networks, employing a range of
different wireless and fixed access technologies. A user could, for
example, pay for and download a video clip to a chosen mobile or fixed
device and subsequently use some of this material to create a
multimedia message for delivery to friends on many different networks.
A single IMS presence-and-availability engine could track a user's
presence and availability across mobile, fixed, and broadband networks,
or a user could maintain a single integrated contact list for all types
of communications.
A key point of IMS is that
it is intended as an open-systems architecture: Services are created
and delivered by a wide range of highly distributed systems (real-time
and non-real-time, possibly owned by different parties) cooperating
with each other. It is a different approach to the more traditional
telco architecture of a set of specific network elements implemented as
a single telco-controlled infrastructure.
For in-depth information
about IMS, check the following resources.
IMS
Resources:
Lucent IMS Service Architecture (pdf)
Lightreading IMS guide
Motoroloa: IMS Whitepaper (pdf)
Ericcsson: IMS Whitepaper (pdf)
Voipplanet.com - IP Multimedia Subsystem
Comments
Hi
Its very best and informative post,A single IMS presence-and-availability engine could track a user's presence and availability across mobile, fixed, and broadband networks, or a user could maintain a single integrated contact list for all types of communications. Its very useful for all.