Study on Web Real Time Communication (WebRTC) access to IP Multimedia Subsystem (IMS); Stage 2
The present document contains a study on the potential modifications of the IMS architecture and stage 2 procedures as required by the support of Web Real Time Communication (WebRTC) clients access to IMS.
For this purpose the present document addresses (non exhaustive list):
- Architectural impacts for the support of different kinds of clients (operator / Third party) in different scenarios.
- The architecture (including the support of WebRTC clients access to IMS for clients on a 3GPP UE that are roaming at access level) for following scenarios:
- when 3GPP or non-3GPP access is used (common IMS).
- when the UE is not roaming at access level or when home-routed access is used (these scenarios have priority for the work).
- evaluate/study whether IMS roaming architecture is used in case of 3GPP LBO.
- Media plane aspects e.g.:
- architectural impacts related to the use of specific codecs: the study addresses transcoding aspects but also the case where the use of 3GPP codecs is possible from the UE.
NOTE: How a WebRTC client / the browser can access to 3GPP codecs on the UE is out of the SA WG2 study scope.
- architectural impacts related to media plane security interworking.
- Authentication and Control plane security related aspects.
- Charging.
- PCC aspects.
- Usage of the 3GPP Packet Core Network to support WebRTC clients access to IMS.
For example the following points had been studied: the PDN connection / PDP context to be used by WebRTC traffic especially in roaming cases and the QoS control, e.g. how a WebRTC client can use the QoS supported / delivered by the 3GPP Packet Core.