Configuring Traversal Server Ports - Cisco TelePresence Administrator's Manual

Field Description
UDP probe The interval (in seconds) with which locally registered endpoints send a UDP probe to the VCS
keep alive Expressway after a call is established, in order to keep the firewall's NAT bindings open.
interval
TCP probe The frequency (in seconds) with which locally registered endpoints send a TCP probe to the
retry interval VCS Expressway.
TCP probe The number of times locally registered endpoints attempt to send a TCP probe to the VCS
retry count Expressway.
TCP probe The interval (in seconds) with which locally registered endpoints send a TCP probe to the VCS
keep alive Expressway after a call is established, in order to keep the firewall's NAT bindings open.
interval

Configuring traversal server ports

The VCS Expressway has specific listening ports used for firewall traversal. Rules must be set on your
firewall to allow connections to these ports. In most cases the default ports should be used. However, you
have the option to change these ports if necessary by going to the
Expressway > Ports).
The options are:
Field
Media demultiplexing RTP port
Media demultiplexing RTCP port
H.323 Assent call signaling port
H.323 H.460.18 call signaling port
See Firewall traversal protocols and ports
Cisco VCS Administrator Guide (X7.1)
Ports
Description
Port used for demultiplexing RTP media.
Default is 2776.
Port used for demultiplexing RTCP media.
Default is 2777.
Port used for Assent signaling.
Default is 2776.
Port used for H.460.18 signaling.
Default is 2777.
for more information.
Firewall traversal
page (VCS configuration >
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