Pipe Groups - D-Link DFL-260E User Manual

10.1.7. Pipe Groups

Set the priority assignment for both rules to Use defaults from first pipe; the default precedence of
both the ssh-in and telnet-in pipes is 2.
Using this approach rather than hard-coding precedence 2 in the rule set, it is easy to change the
precedence of all SSH and Telnet traffic by changing the default precedence of the ssh-in and
telnet-in pipes.
Notice that we did not set a total limit for the ssh-in and telnet-in pipes. We do not need to since the
total limit will be enforced by the std-in pipe at the end of the respective chains.
The ssh-in and telnet-in pipes act as a "priority filter": they make sure that no more than the
reserved amount, 64 and 32 kbps, respectively, of precedence 2 traffic will reach std-in. SSH and
Telnet traffic exceeding their guarantees will reach std-in as precedence 0, the best-effort
precedence of the std-in and ssh-in pipes.
10.1.7. Pipe Groups
NetDefendOS provides a further level of control within pipes through the ability to split pipe
bandwidth into individual resource users within a group and to apply a limit and guarantee to each
user.
Individual users can be distinguished according to one of the following:
• Source IP
• Destination IP
• Source Network
• Destination Network
• Source Port (includes the IP)
• Destination Port (includes the IP)
• Source Interface
• Destination Interface
This feature is enabled by enabling the Grouping option in a pipe. The individual users of a group
can then have a limit and/or guarantee specified for them in the pipe. For example, if grouping is
done by source IP then each user corresponds to each unique source IP address.
A Port Grouping Includes the IP Address
If a grouping by port is selected then this implicitly also includes the IP address. For example, port
1024 of host computer A is not the same as port 1024 of host computer B. It is the combination of
port and IP address that identifies a unique user in a group.
Grouping by Networks Requires the Size
If the grouping is by source or destination network then the network size must also be specified In
other words the netmask for the network must be specified for NetDefendOS.
Note: The return chain ordering is important
Here, the ordering of the pipes in the return chain is important. Should std-in appear
before ssh-in and telnet-in, then traffic will reach std-in at the lowest precedence only
and hence compete for the 250 kbps of available bandwidth with other traffic.
462
Chapter 10. Traffic Management