H323 Profile [1..1] Portallocation - Cisco C20 TelePresence System Administrator's Manual

Cisco TelePresence System Quick Set C20 and Profiles using C20
Contents

H323 Profile [1..1] PortAllocation

The H.323 Port Allocation setting affects the H.245 port numbers used for H.323 call signalling.
Requires user role: ADMIN
Value space: <Dynamic/Static>
Dynamic: The system will allocate which ports to use when opening a TCP connection. The
reason for doing this is to avoid using the same ports for subsequent calls, as some firewalls
consider this as a sign of attack. When Dynamic is selected, the H.323 ports used are from
11000 to 20999. Once 20999 is reached they restart again at 11000. For RTP and RTCP
media data, the system is using UDP ports in the range 2326 to 2487. Each media channel
is using two adjacent ports, ie 2330 and 2331 for RTP and RTCP respectively. The ports are
automatically selected by the system within the given range. Firewall administrators should
not try to deduce which ports are used when, as the allocation schema within the mentioned
range may change without any further notice.
Static: When set to Static the ports are given within a static predefined range [5555-6555].
H323 Profile 1 PortAllocation: Dynamic
Example:
D14637.10 Profile C20 and Quick Set C20 Administrator Guide TC6.1, APRIL 2013.
Introduction Web interface System settings System settings
www.cisco.com — Copyright © 2010-2013 Cisco Systems, Inc. All rights reserved.
63
Administrator Guide
Setting passwords Appendices