Figure 197 Network > Alg; Table 100 Network > Alg - ZyXEL Communications ZyWALL USG 300 User Manual

Figure 197 Network > ALG
The following table describes the labels in this screen.
Table 100 Network > ALG
LABEL
SIP Setting
Enable SIP
Transformations
SIP Media
inactivity time
out
SIP Signaling
inactivity time
out
SIP Signaling
Port
H.323 Setting
Enable H.323
transformations
H.323 Signaling
Port
ZyWALL USG 300 User's Guide
DESCRIPTION
Turn on the SIP ALG to allow SIP sessions to pass through the ZyWALL. SIP is a
signaling protocol used in VoIP (Voice over IP), the sending of voice signals over
Internet Protocol. Enabling the SIP ALG allows you to use bandwidth management
on SIP traffic.
Use this field to set how many seconds (1~86400) the ZyWALL 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
ZyWALL 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 ZyWALL.
If the SIP client does not have this mechanism and makes no calls during the
ZyWALL SIP timeout, the ZyWALL 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.
Configuring port numbers for SIP traffic here also configures the application patrol
feature to use the same port numbers for SIP traffic.
Click the Add icon to add another custom UDP port number for SIP traffic. You can
have a total of up to eight.
Click the Remove icon to delete a custom UDP port number for SIP traffic.
Turn on the H.323 ALG to allow H.323 sessions (used for audio communications) to
pass through the ZyWALL. Enabling the H.323 ALG allows you to use bandwidth
management on H.323 traffic.
If you are using a custom TCP port number (not 1720) for H.323 traffic, enter it here.
Chapter 18 ALG
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