Dynamic Bandwidth Balancing; Pipe Rules; Scenarios: Setting Up Traffic Shaping - D-Link DFL-1600 User Manual

23.3. Pipe Rules

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23.2.3

Dynamic Bandwidth Balancing

As previously stated, per-user bandwidth may be limited by enabling
grouping within a pipe. This may be used to ensure that one group cannot
consume all of the available bandwidth. But what if the bandwidth for the
pipe as a whole has a limit, and that limit is exceeded?
Such problem is addressed by a feature in D-Link firewalls called Dynamic
Balancing. This algorithm ensures that the bandwidth limit of each group
is dynamically lowered (or raised) in order to evenly balance the available
bandwidth between the groups of the pipe. The temporary restriction will
be removed until the configured limit is satisfied.
The dynamic adjustments take place 20 times per second, and will quickly
adapt to changed bandwidth distributions.
Dynamic balancing functions within each precedence of a pipe individually.
This means that if groups are allotted a certain small amount of high
priority traffic, and a larger chunk of best-effort traffic, all groups will get
their share of the high-precedence traffic as well as their fair share of the
best-effort traffic.
23.3 Pipe Rules
Pipe Rules are policies that make decisions of what traffic should be passed
through which pipes. The pipe rule filters the traffic by service type and
interface & network IP addresses, much in the same way as the normal IP
rules. Then, the rule chooses appropriate forward and return pipes to the
traffics, and determines the precedence(priority) on it. When the firewall
receives traffics, it will be able to find these pipe and precedence
information in matching rules, and control the utilization of bandwidth
according to the limits and/or grouping defined in specific pipes.
Remember that only traffic matching a pipe rule will be traffic shaped, and
the first matching rule is the one used.
23.4 : Setting up Traffic Shaping
As seen from the previous sections, in D-Link firewalls, all measuring,
limiting, guaranteeing and balancing is carried out in Pipes. However, a
pipe by itself is meaningless unless it is put into use in the Pipe Rules
D-Link Firewalls User's Guide