ETSI - TR 126 923
Digital cellular telecommunications system (Phase 2+) (GSM); Universal Mobile Telecommunications System (UMTS); LTE; Study on media handling aspects of IP Multimedia Subsystem (IMS) based telepresence
|Publication Date:||1 September 2020|
The present document provides a study on the media handling aspects of IMS-based telepresence in 3GPP services. This includes the investigation of the following areas:
- Media codecs (speech, video, real-time text) for IMS-based telepresence.
- Media configuration including session setup and control procedures for IMS-based telepresence, and media provisioning aspects of capability negotiation based on SDP and CLUE protocols, etc.
- Set-up and control of the individual media streams between clients including interactivity, such as adding and dropping of media components, as well as end-to-end QoS handling, etc. for IMS-based telepresence.
- Data transport including usage of RTP / RTCP protocols, RTP profiles, RTP payload formats, RTP mapping, media synchronization, etc. for IMS-based telepresence, e.g. in relation to negotiation and establishment of the CLUE data channel, and exchange of CLUE ADVERTISEMENT and CONFIGURE messages.
- Requirements and guidelines for media adaptation in IMS-based telepresence, for example in response to changes of network bandwidth.
- Media handling requirements and guidelines for fixed-mobile interworking as well as interworking with MTSI and with GSMA's IMS profile on High-Definition Video Conference (HDVC) service in IR.39.
The gap analysis of the above areas and associated recommendations and conclusions for the proposed improvements are documented in the present document. Study and evaluation of end-to-end quality of experience (QoE) for IMS-based telepresence use cases for various codec, media handling and QoS configurations are also presented.