Outbound Lan Traffic Options - D-Link NetDefend SOHO DFL-160 User Manual

4.1. Outbound LAN Traffic Options

• Anti-Virus scanning can be enabled for file downloads.
• Intrusion Detection and Prevention (IDP) can be enabled to search streams of traffic for threats
against internal resources.
• Time schedules can be set up which can be then used to specify the times when security policies
are applied.
• Lists of users that are allowed to access protected resources can be specified.
The sections that follow describe the options in this menu in the order they appear.
4.1. Outbound LAN Traffic Options
The Meaning of Outbound
These options determine what types of traffic can pass between the LAN network on the protected
"inside" of the DFL-160 and the WAN interface when the connection is initiated by a client or host
on the LAN network.
For instance, the retrieval of data from a web server on the public Internet is still considered part of
outbound traffic if the retrieval request is initiated by a web surfer sitting on the LAN network.
Allowing Services
A Service refers to a higher level protocol such as the HTTP protocol used for web surfing and is a
convenient way of identifying different types of data traffic. The presentation of the first few
choices in the web interface is shown below.
By default, all services are allowed, that is to say, no connections initiated from the LAN network
are blocked.
It is recommended, however, to try and impose restrictions that match the expected needs of the
clients and hosts on the LAN network. For instance, selecting only the HTTP and HTTPS protocols
allows only web surfing to take place from the LAN network and other protocols such as FTP will
not be allowed.
Connections from the LAN to the DMZ
Connections initiated from the LAN network to hosts on the DMZ network are always allowed.
However, the opposite is never true: connections initiated by hosts on the DMZ network are never
allowed to the LAN network.
This arrangement prevents a host that becomes infected on the DMZ spreading the problem to the
LAN network.
Specifying Custom Traffic
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Chapter 4. The Firewall Menu