5 Architectural requirements
23.2813GPPFunctional architecture and information flows to support Mission Critical Video (MCVideo)Release 18Stage 2TS
5.1 Media routing requirements
The video media flow for a private call shall be routed according to one of the following two options:
a) Option 1:
1) Through the primary MCVideo system if both users in the call belong to the same organisation; or
2) Through the primary MCVideo system of each users, if the users in the call do not belong to the same organisation.
b) Option 2: The video media flow may be routed locally, under the control of the primary MCVideo system, through an entity allowing the duplication of the media flow to the primary MCVideo system of each user.
The video media flow for a group call shall be routed to the group home MCVideo system.
5.2 MCVideo group affiliation and MCVideo group de-affiliation
MCVideo group affiliation shall be as specified in clause 5.2.5 of 3GPP TS 23.280 [6]. In addition, the following requirements shall be fulfilled by the MCVideo service for MCVideo users affiliated to MCVideo groups:
– MCVideo users receive notifications for MCVideo group call setup and invitations for their affiliated MCVideo group(s).
– MCVideo users select an affiliated MCVideo group to initiate a new group MCVideo call or transmit media in an existing MCVideo group call.
– MCVideo users receive media and events from their affiliated MCVideo group(s).
5.3 Device inventory requirements
The MCVideo service shall provide device inventory capabilities for MCVideo UEs. The device inventory capabilities shall include:
– device information registration;
– device information storage; and
– device information query.
5.4 Device discovery requirements (off-network)
The MCVideo service shall provide device discovery for devices as requested by the MCVideo user according to the MC service provider policy for off-network operations.
5.5 Bearer management
5.5.1 General
The MCVideo UE shall use the APNs as defined in subclause 5.2.7.0 of 3GPP TS 23.280 [6]. The MCVideo UE shall use the MC services APN as defined in subclause 5.2.7.0 of 3GPP TS 23.280 [6] for the SIP-1 reference point.
5.5.2 EPS bearer considerations
The EPS bearer considerations specified in subclause 5.2.7.2 of 3GPP TS 23.280 [6] shall apply.
5.5.3 EPS unicast bearer considerations for MCVideo
For an MCVideo call session request, resources shall be requested utilising interaction with dynamic PCC. The MCVideo system shall request resources over Rx to a PCRF. It is recommended that the dedicated bearer(s) for video media and control of the video media (i.e. MCVideo‑4 and MCVideo‑7) utilise the QCI values depending on the MCVideo mode of the MCVideo call/session, as per table 5.5.3-1. For transmission and reception control signalling, the QCI value of 69 is recommended as specified in 3GPP TS 23.203 [11]. The request of resources over Rx shall include an application identifier for MCVideo in order for the PCRF to evaluate the correct QCI.
Table 5.5.3-1: QCI values to use for EPS unicast bearers for each MCVideo mode
|
MCVideo mode |
QCI value utilised |
|---|---|
|
Urgent real-time mode |
67 |
|
Non-urgent real-time mode |
67 |
|
Non real-time mode |
4 |
The MCVideo audio media and video media may transmit over separate EPS bearers, in which case the priority for each bearer is determined by the operator policy. Depending on operator policy, the MCVideo system may be able to request modification of the priority (ARP) of an existing bearer without the need to initiate a new dedicated GBR bearer.
NOTE: Operator policy takes into account regional/national requirements.
When MCVideo audio media and video media are multiplexed into one EPS bearer, then different QCI and/or ARP values are not possible for video and audio media.
5.5.4 MBMS bearer management
The MBMS bearer management for MC services is specified in subclause 5.2.7.1 of 3GPP TS 23.280 [6].