Intrusion Detection / Prevention; Traffic Shaping - D-Link DFL-700 - Security Appliance Product Manual

Intrusion Detection / Prevention

The DFL-700 Intrusion Detection/Prevention System (IDS/IDP) is a real-time intrusion
detection and prevention sensor that identifies and takes action against a wide variety of
suspicious network activity. The IDS uses intrusion signatures, stored in the attack database,
to identify the most common attacks. In response to an attack, the IDS will protect the
networks behind the DFL-700 by dropping the traffic. To notify responsible parties of the
malicious attack, the IDS will send e-mails to the system administrators if e-mail alerting is
enabled and configured. D-Link updates the attack database periodically. There are two
modes that can be configured, either Inspection Only or Prevention. Inspection Only will
only inspect the traffic, and if the DFL-700 detects anything it will log, e-mail an alert (if
configured), and pass on the traffic. If Prevention is used the traffic will be dropped and
logged and if configured, an e-mail alert will be sent.

Traffic Shaping

The simplest way to obtain quality of service in a network, seen from a security as well as
a functionality perspective, is to have the components in the network, not the applications, be
responsible for network traffic control in well-defined choke points.
Traffic shaping works by measuring and queuing IP packets, in transit, with respect to a
number of configurable parameters. Differentiated rate limits and traffic guarantees based on
source, destination and protocol parameters can be created; much the same way firewall
policies are implemented.
There are three different priorities when configuring the traffic shaping, Normal, High and
Critical.
Limit works by limiting the inbound and outbound traffic to the specified speed. This is the
maximum bandwidth that can be used by traffic using this policy. Note however that if you
have other policies using limit; which in total is more then your total internet connection and
have configured the traffic limits on the WAN interface this limit is sometimes lowered to allow
traffic with higher priorities to have precedence.
By using Guarantee, you can traffic using a policy a minimum bandwidth, this will only
work if the traffic limits for the WAN interface are configured correctly.
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