Motivation

ITU-T Study Group 16 created the H.248.x sub-series, which decomposed the H.323 Gateway function defined in ITU-T Rec. H.246 into functional subcomponents called Media Gateway Controllers and Media Gateways and specified the protocols these components use to communicate. This enabled H.323 gateways to be composed of components from multiple vendors distributed across multiple physical platforms. This work was done in collaboration with the IETF Megaco Working Group (now closed). The H.248 protocol is applicable to many different types of gateways. H.248 can be used with Media Gateway Controllers terminating a number of call/session control protocols, for example: BICC (which supports multimedia according to Rec. H.320), ISUP, SIP, H.323 and Q.931. H.248 can be used to control media gateways terminating TDM, IP, ATM and AAL2. H.248 has also found application in Mobile 3G networks, IP-Cablecom networks and to control IP Phones. H.248 is an important element in today's softswitch architectures and networks.

Study items

This Question considers multimedia gateway architecture and the development of multimedia gateway control protocols for gateways interworking existing networks and new networks as defined by the Next Generation Network and IPTV groups. Specific study items include the addition of new functionality to the H.248.x sub-series to enable existing and new network nodes to work as a split Media Gateway Controller and Media Gateway. Items of study may also include gating functionality such: QoS control, Network Address Translation (NAT) and firewalling, enhanced conferencing, media streaming control and network access control. New functionality may be required for emerging conferencing architectures from the IETF such as defined in the XCON working group.

New items for enhanced operability between Media Controller and Media Gateways and for enhanced Media Gateway efficiency will also be studied.

Considerations will be given on how to help measure and mitigate climate change.

Tasks

Tasks include, but are not limited to:

• H.248.1 V4 (2008/2009)
• New H.248.x sub-series Recommendations for packages for new study items (continuing)
• Packages Supplement (continuing)
• Enhancement and maintenance of H.248.x sub-series and H-series Supplement 2 (continuing)

An up-to-date status of work under this Question is found in the SG 16 work programme (http://itu.int/ITU-T/workprog/wp_search.aspx?isn_sg=554).

Relationships

Recommendations:

• G.799.1, J.171, H.221, H.223, H.323, H.324, Q.115.0, Q.1950

Questions:

• 1/16 on Multimedia systems, terminals and data conferencing
• 2/16 on H.323 real-time multimedia system
• 4/16 on advanced functions for H.300-series systems and beyond
• 13/16 on IPTV
• 15, 18/16 on TIGIN Gateways
• 27/16 on vehicle gateway platform

Study Groups:

• ITU-T SG 9 on cable gateways
• ITU-T SG 11 on BICC and bearer media control
• ITU-T SG 13 on NGN

Other Bodies:

• 3GPP on gateways (Mc interface) and media resource function
• ETSI TISPAN on NGN, access and residential gateway, gate control
• IETF for Internet matters including MEGACO mailing list
• IANA for package registration matters
• MultiService Forum (MSF)