Traffic shaping is applied on a per-interface basis. The behaviour depends on the sort of interface you shape on. If we select external interfaces, the shaping takes place on the traffic coming out from eBox to the Internet. On the other hand, shaping on internal interfaces affects to traffic coming in from the Internet.
Once you have selected the network interface, it is time to decide which traffic you would like to shape. To do so, we will add rules.
The first three lines of the rule will be used to match traffic. That is, they will be used as a selector for traffic.
This field is used to match a certain protocol. Note that depending on the protocol you pick, you will have to add more extra data to complete the match. For example, if you select TCP, a new field labelled as Port will pop up. You could either leave it blank to match any port or type certain port.
Source is used to match packets based on their origin. The first thing you will have to do is selecting from the combo box what kind of data you will use to match. You have several options:
Source IP. You can introduce an IP or leave it blank to match any IP.
Source object. You can select one of the objects available in eBox. The different members which compose an object will be used to match traffic.
Source MAC. You can introduce a MAC address to match traffic. Note that this option only makes sense when you are adding rules to an external interface, as you have information about your MAC source addresses belonging to your local network.
Destination is used to match packets based on their destination. The steps to take are similar to those for Source. First of all, you have to pick an option from the combo box to tell the system which sort of data will be used to carry out the match for the current rule.
Destination IP. You can introduce an IP or leave it blank to match any IP.
Destination object. You can select one of the objects available in eBox. The different members which compose an object will be used to match traffic.
Let's recap. In the first three lines of a rule you have selected the kind of traffic you would like to shape. The next step consists of deciding what we would like to do with that traffic. For example, if we are managing a protocol which is very critical for the normal working of our business, it is quite likely that we would like to prioritise it, or set a minimum quality of service for it.
The last three lines of a rule priority, guaranteed rate, and maximum rate are used to make that kind of decision. Let us walk through them to give you a bit of background.
This field is used to enqueue network packets in different queues with different priorities. Priority ranges from 0 to 7, the smaller priority number, the higher priority. Using this field for different services, destination or source addresses is a good method to establish your prioritasing policy for your network traffic. It is an easy way of assure more priortiity for those services which are critical for your organisation and relegate those which are not.
This field tells eBox which should be the minimum rate for the traffic matching the current rule. The rate ranges from 60 kbits to your connection bandwidth.
You have to take into account two important things. eBox will not allow you to set a guaranteed rate which is impossible to achieve given your connection bandwidth, as usual, if you are adding rules to your external interface you are dealing with your upload capacity, in case of your internal interface, download capacity. If you set the guaranteed rate to zero, you are telling eBox not to assure anything, and it will just do a best-effort for that kind of traffic.
If the guaranteed rate field sets a lower boundary for the rate, this field can be used to put a ceiling on the upload or download rate that (your matched by the rule) traffic can reach.
By setting this field to zero, you are telling eBox not to set any ceiling.