ETSI TISPAN - Standardization of the NGN IMS for fixed networks

TISPAN is an ETSI technical standardization committee whose aim is to produce specifications for the distribution of telephony, VoIP and multimedia services in the context of the emergence of a new generation of IP-based networks (NGN, Next Generation Network).

To fully understand the importance of TISPAN and its objectives, we need to introduce the concept of NGN. Next-generation networks (NGNs) are service distribution networks taking advantage of the widespread deployment of networks commonly referred to as IP, an interconnection system exploiting the IP protocol and based on the notion of packets as opposed to the circuit-switched notion that has hitherto underpinned telephony service systems, and aiming to offer consumer benefits such as :

• interoperability between a large number of services, on different types of access (ADSL, 3G mobile, etc.) and guaranteeing levels of security and reliability (notion of quality of service specific to so-called managed networks, as opposed to the "open Internet" or "free Internet");

• an opening for new suppliers of real-time or non-real-time communication services in a client/server configuration;

• nomadicity and mobility for both users and equipment;

• regulatory compliance, including interception, number portability, emergency numbers, etc.

TISPAN's motivation in relation to the technological emergence of NGN is primarily to produce a standardized specification for the development of services over IP networks, while distinguishing itself from the markets for the distribution of services over unmanaged IP networks (a well-known example is "Skype" for telephony, a service with no guarantee of quality).

For TISPAN, this means setting up a task force to write standardized specifications covering :

• telephony (voice over IP) ;

• interoperability of its services with other networks such as the mobile network;

• multimedia (e.g. TV, video-on-demand).

We'll see in the rest of this document that the notion of multimedia has evolved considerably over the life of the TISPAN organization, from its initial focus on interpersonal services such as videotelephony, to the very broad notion of video services such as TV and the distribution of video content, whether produced for monetization by content creators or self-produced by users.

The intention here is to present a rather high-level description of the NGN (Next Generation Network) specified within the ETSI TISPAN technical committee. The...