How To Create a Layer 7 Firewall in MikroTik

Layer 7 is the Application layer of the OSI system model and allows the MikroTik router to analyze each and every packet that enters your network, and decide what to do with it.

The first step is to get a script file with the list of the most common Layer 7 protocols. This can be obtained from the MikroTik Wiki via the following link:

http://www.mikrotik.com/download/l7-protos.rsc

We can now copy this script file into the MikroTik Files list.

Once you have the script file copied into the Files window we can now proceed to import it via the terminal.

To make sure the script file imported properly, head to the IP -> Firewall menu and go to the Layer 7 Protocols tab. You should now have a list of the most common types of traffic found within a network.

We can now create a firewall rule to block any type of Layer7 traffic we choose. Go to the Filter tab and add a new firewall rule. Leave the chain set to forward.

In the Advanced tab you may now choose the Layer7 traffic type you would like to block/allow.

Once the Layer7 traffic type has been selected, proceed to the Action tab and define the action of your choice. Drop is the most common action to stop a certain type of traffic flowing through your network.

Tutorial by Chris SutherlandMiro distributionwww.miro.co.za