Since its creation in 2003, ETSI TISPAN (Telecommunications and Internet converged Services and Protocols for Advanced Networking) has been the key standardization body in creating the Next Generation Networks (NGN) specifications.
NGN Release 1 was finalized in December 2005, provided the robust and open standards that industry required for the development, testing  and implementation of the first generation of NGN systems. NGN Release 1 specifications adopt the 3GPP IMS (IP Multimedia Subsystem) standard for SIP-based applications, but also add further functional blocks and subsystems to handle non-SIP applications. Initially TISPAN worked on harmonizing the IMS core for both wireless and wireline networks. However in early  2008, the common IMS specifications were transferred back to 3GPP so that one unique standards organization be responsible for providing a Common IMS fitting any network (fixed, 3GPP, CDMA2000, etc.).
NGN Release 2 was finalized early 2008, and added key element to the NGN such as IMS and non IMS based IPTV, Home Networks and devices, as well as NGN interconnect with Corporate Networks. TISPAN IPTV specifications answer the emerging market needs such as triple-play and quadruple-play service offers: access independent solutions, integration in a multi-service environment, availability of enhanced services combining features from every component of the triple/quadruple-play offers.
TISPAN defines two IPTV solutions: an IPTV dedicated subsystem focused on the integration of existing market solutions in an NGN environment; and an IMS-based IPTV solution allowing blending the TV services with other Telecommunication services (e.g. voice, presence, and data services).
In the highly dynamic domain of Home Networks, TISPAN is actively defining the service requirements and capabilities for customer’s home networks to be connected to the NGN. This includes the definition of the Customer Network Gateway Architecture and reference points, and Customer Devices architecture and Reference Points.
To further enhance the IPTV support by the NGN, TISPAN defines the architecture and reference points of a customer network device for IMS based IPTV services. Despite the enormous progress made on the NGN support of new IP enables services, TISPAN is moving forward with making specification to ensure the NGN is an implemented  success.
Since early 2008, TISPAN has begun work on the third release of NGN specifications and are now presently looking at IPTV enhancements, IP network interconnection, NGN security enhancements, and QoS with overload control amongst other permanently evolving NGN requirements.

TISPAN is the ETSI core competence centre for fixed networks and their migration to Next Generation Networks.