Detection Prevention; Network Connection Inactivity Timeout - Dell SonicWALL GX250 Manual

LAN In
If a LAN In checkbox is checked, users on the Internet may access all computers on
your LAN for that service. By default, LAN In checkboxes are not checked; use caution
when enabling. The LAN In column is not displayed if NAT is enabled.
DMZ In (Optional)
If a DMZ In checkbox is checked, users on the Internet may access that service on
the DMZ. Otherwise, they are blocked from accessing that service on the DMZ. By
default, DMZ In checkboxes are checked.
Note: If an Alert Icon appears next to a LAN Out, LAN In, or DMZ In checkbox, a rule
in the Rule window modifies that service.
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Public LAN Server
A Public LAN Server is a LAN server that is designated to receive inbound traffic for
a specific service, such as Web or E-mail. You may define a Public LAN Server by
entering the server's IP address in the Public LAN Server field for the appropriate
service. If you do not have a Public LAN Server for a service, enter "0.0.0.0" in the field.
See Creating a Public LAN Server on the following page for more information.
Windows Networking Pass Through
Computers running Microsoft Windows communicate with one another through
®
NetBIOS broadcast packets. By default, the SonicWALL blocks these broadcasts. If you
check the Windows Networking checkbox, your SonicWALL allows NetBIOS
broadcasts from LAN to DMZ or from LAN to WAN. Then, LAN users are able to view
machines on the DMZ and on the WAN in their Windows Network Neighborhood.

Detection Prevention

Enable Stealth Mode
By default, the SonicWALL responds to incoming connection requests as either
"blocked" or "open". If you enable Stealth Mode, your SonicWALL does not respond
to blocked inbound connection requests. Stealth Mode makes your SonicWALL
essentially invisible to hackers.
Randomize IP ID
A Randomize IP ID checkbox is available to prevent hackers using various detection
tools from detecting the presence of a SonicWALL appliance. IP packets are given
random IP IDs which makes it more difficult for hackers to "fingerprint" the SonicWALL
appliance. Use this checkbox for additional security from hackers.

Network Connection Inactivity Timeout

If a connection to a remote server remains idle for more than five minutes, the
SonicWALL closes the connection. Without this timeout, Internet connections could
Page 82 NETWORK ACCESS RULES