Netgear UTM25-100NAS User Manual
ProSecure Unified Threat Management UTM10 or UTM25 Reference Manual
5-24
Firewall Protection
v1.0, September 2009
5. Click Apply to save your settings.
Managing the Application Level Gateway for SIP Sessions
The Application Level Gateway (ALG) facilitates multimedia sessions such as voice over IP
(VoIP) sessions that use the Session Initiation Protocol (SIP) across the firewall and provides
support for multiple SIP clients. ALG support for SIP is disabled by default.
(VoIP) sessions that use the Session Initiation Protocol (SIP) across the firewall and provides
support for multiple SIP clients. ALG support for SIP is disabled by default.
To enable ALG for SIP:
1. Select Network Security > Firewall from the menu. The Firewall submenu tabs appear.
2. Click the Advanced submenu tab. The Advanced screen displays (see
).
Table 5-5. Session Limit Settings
Setting
Description (or Subfield and Description)
Session Limit
User Limit Parameter
From the User Limit Parameter pull-down menu, select one of the following
options:
• Percentage of Max Sessions. A percentage of the total session connection
options:
• Percentage of Max Sessions. A percentage of the total session connection
capacity of the UTM.
• Number of Sessions. An absolute number of maximum sessions.
User Limit
Enter a number to indicate the user limit.
If the User Limit Parameter is set to Percentage of Max Sessions, the number
specifies the maximum number of sessions that are allowed from a single-
source device as a percentage of the total session connection capacity of the
UTM. (The session limit is per-device based.)
If the User Limit Parameter is set to Number of Sessions, the number specifies
an absolute value.
Note: Some protocols such as FTP and RSTP create two sessions per
connection, which should be considered when configuring a session limit.
If the User Limit Parameter is set to Percentage of Max Sessions, the number
specifies the maximum number of sessions that are allowed from a single-
source device as a percentage of the total session connection capacity of the
UTM. (The session limit is per-device based.)
If the User Limit Parameter is set to Number of Sessions, the number specifies
an absolute value.
Note: Some protocols such as FTP and RSTP create two sessions per
connection, which should be considered when configuring a session limit.
Total Number of
Packets Dropped due
to Session Limit
Packets Dropped due
to Session Limit
This is a non-configurable counter that displays the total number of dropped
packets when the session limit is reached.
packets when the session limit is reached.
Session Timeout
TCP Timeout
For each protocol, specify a timeout in seconds. A session expires if no data for
the session is received for the duration of the timeout period. The default
timeout periods are 1200 seconds for TCP sessions, 180 seconds for UDP
sessions, and 8 seconds for ICMP sessions.
the session is received for the duration of the timeout period. The default
timeout periods are 1200 seconds for TCP sessions, 180 seconds for UDP
sessions, and 8 seconds for ICMP sessions.
UDP Timeout
ICMP Timeout