D-Link NetDefend DFL-210 User Manual page 225

10.1.4. Pipes Basics
1. Go to Traffic Management > Traffic Shaping > Pipes > Add > Pipe
2. Specify a suitable name for the pipe, for instance std-in.
3. Enter 2000 in Total textbox.
4. Click OK.
However, simply creating the pipe will not accomplish much; traffic actually needs to be passed through the pipe.
This is done by assigning the pipe to an IP rule.
We will use the above pipe to limit inbound traffic. This limit will apply to the the actual data packets, and not the
connections. In traffic shaping we're interested in the direction that data is being shuffled, not which computer initi-
ated the connection.
Create a simple rule that allows everything from the inside, going out. We add the pipe that we created to the re-
turn chain. This means that the packets travelling in the return direction of this connection (outside-in) should pass
through the "std-in" pipe.
CLI
gw-world:/> add PipeRule ReturnChain=std-in SourceInterface=lan
Web Interface
1. Go to Traffic Management > Traffic Shaping > Pipes > Add > PipeRule
2. Specify a suitable name for the pipe, for instance Outbound.
3. Now enter:
• Service: all_services
• Source Interface: lan
• Source Network: lannet
• Destination Interface: wan
• Destination Network: all-nets
4. Under the Traffic Shaping tab, make std-in selected in the Return Chain control.
5. Click OK.
This setup limits all traffic from the outside (the Internet) to 2 megabits per second, much the same as if a 256
kbps Internet connection had been the bottleneck. No priorities are applied, nor any dynamic balancing.
10.1.4.3. Two-Way Bandwidth Limits
The previous example will only limit bandwidth in the inbound direction. We chose this direction
simply because in most setups, it is the direction to first become full. Now, what if we want to limit
bandwidth in both directions?
The answer is "simple! Apply the 2 Mbps limit in the forward direction as well!". Well, yes. But
how?
Simply inserting "std-in" in the forward chain will not work. At least not the way you most likely
want it to work. You probably want the 2 Mbps of outbound traffic to be separate from the 2 Mbps
of inbound traffic, right?
So why doesn't the simple solution work? Well, as we've said before, pipes are simple things. If you
try to pass 2 Mbps of outbound traffic through the pipe in addition to the 2 Mbps of inbound traffic,
it would add up to 4 Mbps. Since the limit is at 2 Mbps, what you'd get is something like 1 Mbps in
each direction.
SourceNetwork=lannet DestinationInterface=wan
DestinationNetwork=all-nets Service=all_services name=Outbound
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Chapter 10. Traffic Management