Astroflow, just like most common bandwidth managers needs certain parameters in order to function correctly. This guide will give you some insight on how to get the most out of AstroFlow.

After downloading and successfully installing AstroFlow you will need to configure a few variables before you can login to the user interface.

After pointing your browser to the IP address you specified at install you will be asked to agree to the licence agreement and to provide initial setup information to get AstroFlow running on your network. You will also require a valid DEMO key which may be obtained from the Netsoft.co.za website. In order to obtain this key you will need to register as a user of AstroFlow. This is simple, all you need to do is complete an online registration form and a DEMO key will be sent to your e-mail address.

In order for the AstroFlow bandwidth manager to work it must be installed inline on the network. The two network cards have been configured to work in bridge mode which means that the AstroFlow machine will get assigned a single IP address and not two as one would normally do. This will allow traffic to continue to flow as normal as long as the AstroFlow server is powered on. Please refer to the image below for a simple diagram of where the AstroFlow server should be installed on a network for optimal performance. In order for AstroFlow to effectively manage a network it should always be installed in this fashion, as in this position all network traffic entering and leaving the network will be shaped. This will ensure network stability as well as ensuring that mission critical traffic is given priority over traffic that is of little importance to the internal workings of a private network.

In order to effectively use the system you will need to follow the following steps in this order:

1. You have the option of naming all the hosts or networks you would like to manage. This is useful as these names will become available everywhere in the application.

2. You will have to define classes that these hosts or networks will be assigned to.

3. You can then assign filters to these classes.
We go into these steps in more detail in the following paragraphs.

This section will describe the overall process of how AstroFlow managers bandwidth.

AstroFlow needs to know your total amount of bandwidth in order for it to effectively manage traffic flow. This bandwidth would be assigned to your incoming and outgoing classes. These are the main classes and your total amount of bandwidth will be assigned to them. You would then create sub-classes in order to split up your bandwidth according to priority or assigning different bandwidth guarantees to clients. You could effectively think of it as a family tree as in Figure 2. Every time you split a class or create sub-classes the total amount of bandwidth you can assign to sub-classes cannot exceed the total amount of bandwidth assigned to their parents.

For example:

I have 512K total bandwidth for incoming and 512K for outgoing. I would create four different classes. Critical priority, high priority, medium priority and low priority. For each sub-class I would assign guaranteed and burst bandwidth according to my priority. For instance, critical priority would get 256K guaranteed and be allowed to burst to 512K thus, guaranteeing 256K to this class. My high priority, I would assign 128K and allow it to burst to 512K. My medium priority would get 96K and burst 512K and my low priority sub-class will get the remaining 32K also allowing to burst to 512K. So as you can see the guaranteed bandwidth for the classes are greater according to the priorities but the burst rates are all the same allowing each class to borrow bandwidth from the root class if surplus bandwidth is available. So, if no high priority class bandwidth is being used that bandwidth becomes pooled making it available for other classes that may require it.

Bursting is optional and if set to zero or left blank disables it. So even if surplus bandwidth is available but a class has no burst rate, that class will not be able to transfer data above its guaranteed rate.

In AstroFlow the priority of classes go according to their order. The first class will have the highest priority and thus the last the lowest. Classes can be sorted by clicking on the up or down arrows to the left of the class.

Taking the above scenario we can go even further and create sub-classes off of our critical priority class and do the same as above. We could, for instance, create four classes and call them HTTP, SMTP, POP3 and VPN and assign equal bandwidth to each class thus guaranteeing each of these critical services an equal share of our priority class. The burst rate also applies. Each one of these can have the option of bursting to 256K. This could again be split up to more classes and so on.

So as you can see, from Figure 2 that guarantees can be met from within guarantees thus being able to guarantee service levels.

Filters are rules that enforce traffic flow. These filters are added to classes, so whichever class the filter falls into that bandwidth will be applied.

You define filters by clicking on a class in the left window and then clicking on 'add filter' in the right window. You will then be presented with a filter add page as in Figure 4.

Filters can be quite tricky as you need to know the protocols, ports and IP addresses you want to filter and in what direction they are going.

For instance, if you would like to limit just traffic going to an IP address that is on the inside of your network, the filter would be quite easy to add. You would select the class you want from the incoming root class and add a filter with a protocol of IP, a source address and port of any, a destination address of any host you would like to limit and a destination port of any.

So, as you can see the class is incoming and the destination is defined. You also have the option of adding a reverse rule to an outgoing class which would effectively manage the bandwidth in the opposite direction.

Basically, it would swap your source addresses and ports for destination addresses and ports.
The same applies to ports, TOS and ICMP filters.