3.4.1. Restrictions 
- Video endpoints are only supported at OpenScape 4000 SoftGate and STMIX/STMIY
- No interworking with HFA video endpoints and TDM video endpoints.
- Video is only possible for DMC slave connections.
- A video connection cannot be added to an existing audio connection and SDP re-negotiation cannot be performed (e.g. video/audio codecs) if the DMC connection is already ongoing.
- The DMC connection (Video) is interrupted if features such as hold, transfer, forward are used. Video connections cannot be established while these functions are active.
- The DMC connection is only re-established and video connections can only be set up again in case of retrieve after hold.
- Since ongoing DMC connections do not support SDP re-negotiation, no applications are supported in conjunction with a video connection (e.g. remote camera control).
- To support secure direct payload in transit scenarios all involved trunks have to be configured to the same RTP security mode.