20 Interworking with MBS Application Provider (AF/AS)
29.5613GPP5G SystemInterworking between 5G Network and external Data NetworksRelease 17Stage 3TS
20.1 General
MB-UPF is used for interworking with the MBS Application Provider (AF/AS) in user plane directly with N6mb reference point, or may be optionally interworking with the MBSTF with the Nmb9 reference point and the MBSTF interworking with the MBS AF/AS with the Nmb8 reference point.
20.2 MBS interworking user plane reference point architecture
Figure 20.2-1 depicts the MBS interworking user plane architecture with the reference point representation.
Figure 20.2-1: MBS interworking user plane reference point architecture
NOTE: Regarding the functionalities, Nmb9 and N6mb are identical, refer to 3GPP TS 23.247 [60].
20.3 User Plane Protocol between MB-UPF and AF/MBSTF
The MBS interworking user plane protocol stack in case of shared delivery is described in Figure 20.3-1 and Figure 20.3-2. In Figure 20.3-1, the UDP tunnel applies to N6mb and Nmb9, while in Figure 20.3-2, the plain IP multicast applies to N6mb.
Figure 20.3-1: User Plane Protocol Stack for N6mb/Nmb9 (UDP Tunnel)
Figure 20.3-2: User Plane Protocol Stack for N6mb (plain IP multicast)
20.4 User Plane Protocol between MBSTF and AF/AS
The MBS interworking user plane protocol stack used in Nmb8 reference point with TCP/IP for Object Distribution Method is described in Figure 20.4-1, with UDP/IP for Packet Distribution Method with Proxy mode or Forward-only mode is described in Figure 20.4-2, with RTP/UDP/IP for Packet Distribution Method with RTP streaming mode is described in Figure 20.4-3.
Figure 20.4-1: User Plane Protocol Stack for Nmb8 used in Object Distribution Method
Figure 20.4-2: User Plane Protocol Stack for Nmb8 used in Packet Distribution Method with Proxy mode or Forward-only mode
NOTE: Detail refer to 3GPP TS 26.502 [61] Annex B.