How communication works
Cisco TelePresence Movi Administrator Guide (4.1)
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1. Go to
VCS Configuration > Local zone > Traversal subzone
.
2. Set the Traversal media port start and Traversal media port end.
Note that in both cases, the port numbers used will be consecutive, but chosen randomly within the
specified range.
Duo video–Binary Floor Control Protocol (BFCP)
Movi supports BFCP for handling the control of duo video. BFCP communication can be sent over a
UDP or a TCP link. Movi uses the same ports as for audio and video for this communication.
On the Cisco VCS, a port will be chosen at random from the same range that has been assigned to the
media links.
Traversal calls
Media links can be established directly between the two endpoints in non-traversal calls, or between
Movi and the Cisco VCS in traversal calls. As a general rule, non-traversal calls are defined as calls
between two participants that are on the same network and do not require interworking.
Note that SIP to H.323 calls require interworking and are therefore traversal calls irrespective of whether
the endpoints are on the same network. For detailed information, see the latest Cisco VCS Administrator
guide.
Media routing
Cisco TelePresence Movi supports Interactive Connectivity Establishment (ICE) for better media
routing. ICE will be used if enabled both in Movi and the far end.
Media routing without ICE
When the ICE protocol is used in a call, media links are established directly between the two endpoints
in non-traversal calls, or between Movi and the VCS in traversal calls. As a general rule, non-traversal
calls are defined as calls between two participants that are on the same network and that don’t require
interworking.
Note that SIP to H.323 calls require interworking and are therefore traversal calls irrespective of whether
the endpoints are on the same network. For detailed information, see the latest VCS Administrator
Guide.
Media routing with ICE
ICE dynamically discovers the best possible path for media to travel between call participants.
It is possible to further improve the routing of media and force it through dedicated links by using the
Enable MNS Mode
Provisioning configuration.
Enabling ICE
Media routing using ICE requires a TURN server. VCS Expressway running version X5.2 or later can
function as a TURN server if it has TURN Relay licenses. Having the TURN server option key is
required.
