Introduction

22.2333GPPRelease 17Stage 1Transparent end-to-end packet-switched streaming serviceTS

3G mobile systems, through the increase in available bandwidth, offer new possibilities and services. One of these new services will be the ability to stream sound and movies to mobile devices.

Streaming is a mechanism whereby media content can be rendered at the same time that it is being transmitted to the client over the data network.

Streaming services are required whenever instant access to multimedia information needs to be integrated into an interactive media application. This has to be seen in contrast to other multimedia services like for instance MMS where multimedia content is delivered to the user asynchronously by means of a “message”.

Interactive applications that use streaming services include on-demand and live information delivery applications. Examples of the first category are music, music videos and news-on-demand applications. Live delivery of radio and television programs are examples of the second category, this could e.g. make it possible to listen to domestic radio while abroad.

A web server works with requests for information, it delivers that particular information as fast as possible, completes the transaction, disconnects and goes on to other requests. A client connects to a web server only when it needs information. This strategy works well as long as pictures and text are to be received. If a client wants to watch video or listen to audio, the entire file must be received before it can be played. The problem is that these kinds of files can be very large thus potentially causing storage problems in the client and resulting in long start-up latency. A streaming service improves this by allowing the media to be consumed as it is received, thereby reducing the latency and removing the need to store the media.

In addition to providing the streaming mechanism the PSS also encompasses the composition of media objects thereby allowing compelling multimedia services to be provisioned. For instance, a mobile cinema ticketing application would allow the user to view the film trailers.