RealPresence Collaboration Server (RMX) 1500/1800/2000/4000 Administrator’s Guide
Polycom®, Inc. 815
Keep Alive Frequency

The Keep Alive frequency is set by the SIP Server using the Via Header keep and Flow Timer fields of the

SIP Header.

If the Collaboration Server is functioning as the server, the Keep Alive frequency is set according to the hard

coded values listed in the following table.

SIP_TCP_KEEPALIVE_TYPE RFC6223
Behavior is the same as for RFC5626 with the following differences:
In the SIP Header, the Via Header “keep” is mandatory.
In the SIP Header, the Flow-Timer Header Field is optional.
PLCM (Default when Generic SIP Server Type is selected for the Network
Service).
For Call and successful Register Dialogues:
Two CR LF character sequences are sent
No PONG response is expected
SIP_TCP_KEEP_ALIVE_BEHAVIOR If the value of the System Flag, SIP_TCP_KEEPALIVE_TYPE= RFC5626
or RFC6223 and no Pong is received, the value of this System Flag is
checked.
Possible Values:
• RE_REGISTRATION_WHEN_NO_PONG_RESPONSE
• DO_NOT_RE_REGISTRATION_WHEN_NO_PONG_RESPONSE
(Default)
For a full description see the description for the
SIP_TCP_KEEPALIVE_TYPE flag (above).
Keep Alive - Frequency
Field Seconds
SIP_TCP_KEEPALIVE_DISABLE None
SIP_TCP_KEEPALIVE_MS 300
SIP_TCP_KEEPALIVE_5626 60
SIP_TCP_KEEPALIVE_6223
SIP_TCP_KEEPALIVE_PLCM
System Flags - SIP_TCP_KEEPALIVE_TYPE / BEHAVIOR
Flag Possible Flag Values