Traffic Shaping - D-Link NetDefend SOHO DFL-160 User Manual

4.9. Traffic Shaping

4.9. Traffic Shaping
Traffic Shaping allows the administrator to control the level of flows for different types of traffic
between the public Internet connected to the WAN interface and hosts on the LAN and DMZ
networks.
For example, we may want to specify how much of the available bandwidth is used for FTP
downloads from the internet. Traffic shaping allows us to do this by setting up a rule that triggers on
FTP traffic and that has the desired maximum specified.
Instead of, or as well as, specifying a maximum we can also use traffic shaping to specify a
guarantee for how much of the total bandwidth will be available for a particular traffic type. For
example, we could guarantee that FTP download traffic will always get at least a tenth of the total
bandwidth if it is needed. As explained later, Priorities help to resolve competing guarantees.
Setting Up traffic Shaping
After selecting the Traffic Shaping menu option in the Firewall menu, we must first click the box
that enables the option.
Specifying WAN Capacity
Next, it is necessary to specify the total available maximum downstream and upstream capacity of
the Internet link connected to the WAN interface.
Adding Rules
After specifying the total capacity, we next must add Traffic Shaping Rules each of which identify a
particular type of traffic to shape and what amount of bandwidth that traffic is allowed and/or what
amount is to be guaranteed.
Click the Rules tab to begin adding individual traffic shaping rules.
When the Add button is pushed, the dialog for entering a traffic shaping rule is displayed.
Important: The total capacity should be correctly specified
It is important to specify the total capacity on the WAN interface as accurately as
possible. Failure to do so may result in unexpected behaviour.
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Chapter 4. The Firewall Menu