ZyXEL Communications NXC5200 User Manual page 229

The following table describes the labels in this screen.
Table 79 Configuration > Network > ALG
LABEL
Enable SIP ALG
Enable SIP
Transformations
Enable Configure
SIP Inactivity
Timeout
SIP Media
Inactivity
Timeout
SIP Signaling
Inactivity
Timeout
SIP Signaling
Port
Enable H.323
ALG
Enable H.323
Transformations
H.323 Signaling
Port
Additional H.323
Signaling Port
for
Transformations
NXC5200 User's Guide
DESCRIPTION
Turn on the SIP ALG to detect SIP traffic and help build SIP sessions
through the NXC's NAT. Enabling the SIP ALG also allows you to use
the application patrol to detect SIP traffic and manage the SIP traffic's
bandwidth.
Select this to have the NXC modify IP addresses and port numbers
embedded in the SIP data payload.
You do not need to use this if you have a SIP device or server that will
modify IP addresses and port numbers embedded in the SIP data
payload.
Select this option to have the NXC apply SIP media and signaling
inactivity time out limits.
Use this field to set how many seconds (1~86400) the NXC will allow a
SIP session to remain idle (without voice traffic) before dropping it.
If no voice packets go through the SIP ALG before the timeout period
expires, the NXC deletes the audio session. You cannot hear anything
and you will need to make a new call to continue your conversation.
Most SIP clients have an "expire" mechanism indicating the lifetime of
signaling sessions. The SIP user agent sends registration packets to
the SIP server periodically and keeps the session alive in the NXC.
If the SIP client does not have this mechanism and makes no calls
during the NXC SIP timeout, the NXC deletes the signaling session
after the timeout period. Enter the SIP signaling session timeout value
(1~86400).
If you are using a custom UDP port number (not 5060) for SIP traffic,
enter it here. Use the Add icon to add fields if you are also using SIP
on additional UDP port numbers.
Turn on the H.323 ALG to detect H.323 traffic (used for audio
communications) and help build H.323 sessions through the NXC's
NAT. Enabling the H.323 ALG also allows you to use the application
patrol to detect H.323 traffic and manage the H.323 traffic's
bandwidth.
Select this to have the NXC modify IP addresses and port numbers
embedded in the H.323 data payload.
You do not need to use this if you have a H.323 device or server that
will modify IP addresses and port numbers embedded in the H.323
data payload.
If you are using a custom TCP port number (not 1720) for H.323
traffic, enter it here.
If you are also using H.323 on an additional TCP port number, enter it
here.
Chapter 15 ALG
229