D-Link NetDefend DFL-1660, User Manual

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Just inserting std-in in the forward chain will not work since we probably want the 2 Mbps limit for
outbound traffic to be separate from the 2 Mbps limit for inbound traffic. If 2 Mbps of outbound
traffic attempts to flow through the pipe in addition to 2 Mbps of inbound traffic, the total
attempting to flow is 4 Mbps. Since the pipe limit is 2 Mbps, the actual flow will be close to 1 Mbps
in each direction.
Raising the total pipe limit to 4 Mbps will not solve the problem since the single pipe will not know
that 2 Mbps of inbound and 2 Mbps of outbound are the intended limits. The result might be 3 Mbps
outbound and 1 Mbps inbound since this also adds up to 4 Mbps.
Using Two Separate Pipes Instead
The recommended way to control bandwidth in both directions is to use two separate pipes, one for
inbound and one for outbound traffic. In the scenario under discussion each pipe would have a 2
Mbps limit to achieve the desired result. The following example goes through the setup for this.
Example 10.2. Limiting Bandwidth in Both Directions
Create a second pipe for outbound traffic:
Command-Line Interface
gw-world:/> add Pipe std-out LimitKbpsTotal=2000
Web Interface
1. Go to: Traffic Management > Traffic Shaping > Pipes > Add > Pipe
2. Specify a name for the pipe, for example std-out
3. Enter 2000 in Total textbox
4. Click OK
After creating a pipe for outbound bandwidth control, add it to the forward pipe chain of the rule created in the
previous example:
Command-Line Interface
gw-world:/> set PipeRule Outbound ForwardChain=std-out
Web Interface
1. Go to: Traffic Management > Traffic Shaping > Pipe Rules
2. Right-click on the pipe rule that was created in the previous example and choose Edit
3. Under the Traffic Shaping tab, select std-out in the Forward Chain list
4. Click OK
This results in all outbound connections being limited to 2 Mbps in each direction.
10.1.5. Creating Differentiated Limits Using Chains
In the previous examples a static traffic limit for all outbound connections was applied. What if the
aim is to limit web surfing more than other traffic? Assume that the total bandwidth limit is 250
kbps and 125 kbps of that is to be allocated to web surfing inbound traffic.
10.1.5. Creating Differentiated Limits
Using Chains Chapter 10. Traffic Management
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