ZyXEL Communications unified security gateway manual 356

Chapter 19 ALG

Table 98 Configuration > Network > ALG (continued)

LABEL	DESCRIPTION
Enable Configure	Select this option to have the ZyWALL apply SIP media and signaling
SIP Inactivity	inactivity time out limits.
Timeout
SIP Media	Use this field to set how many seconds (1~86400) the ZyWALL will
Inactivity	allow a SIP session to remain idle (without voice traffic) before
Timeout	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.
SIP Signaling	Most SIP clients have an “expire” mechanism indicating the lifetime of
Inactivity	signaling sessions. The SIP user agent sends registration packets to
Timeout	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).
SIP Signaling	If you are using a custom UDP port number (not 5060) for SIP traffic,
Port	enter it here.
Additional SIP	If you are also using SIP on an additional UDP port number, enter it
Signaling	here.
Port(UDP) for
Transformations
Enable H.323	Turn on the H.323 ALG to detect H.323 traffic (used for audio
ALG	communications) and help build H.323 sessions through the ZyWALL’s
	NAT.
Enable H.323	Select this to have the ZyWALL modify IP addresses and port numbers
Transformations	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.
H.323 Signaling	If you are using a custom TCP port number (not 1720) for H.323
Port	traffic, enter it here.
Additional H.323	If you are also using H.323 on an additional TCP port number, enter it
Signaling Port	here.
for
Transformations
Enable FTP ALG	Turn on the FTP ALG to detect FTP (File Transfer Program) traffic and
	help build FTP sessions through the ZyWALL’s NAT.
Enable FTP	Select this option to have the ZyWALL modify IP addresses and port
Transformations	numbers embedded in the FTP data payload to match the ZyWALL’s
	NAT environment.
	Clear this option if you have an FTP device or server that will modify IP
	addresses and port numbers embedded in the FTP data payload to
	match the ZyWALL’s NAT environment.
FTP Signaling	If you are using a custom TCP port number (not 21) for FTP traffic,
Port	enter it here.

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	ZyWALL USG 20/20W User’s Guide