To attack network protocols, you need to understand the basics of computer networking.
The more you understand how common networks are built and function, the easier it will be applied to
the knowledge to capturing, analyzing and exploiting new protocols.
Through this section, I will introduce the basic network concepts and and that you will encounter every
day when you are analyzing network protocols.
I will also lay the groundwork for a way to think about the network protocols, making it easier to
find previously unknown security uses during your analysis.
So let's get started with by the network architecture and protocols here.
Network.
This is our topic here that you will learn about.
So let's start by reviewing some basic networking terminology and asking the fundamental question What
is a network?
So the network is a set of two or more computers connected together to share information, and it's
a common to refer to each connected device as a node.
Here, as you can see here, workstation node, mainframe node, server node.
And this is our network here.
So the so it's common to refer to each connected device as a node on the network to make the description
applicable to a wide range of devices.
Here you are seeing a very simple example of our nodes here.
So this diagram shows three nodes connected with a common network and each node might have a different
operating system or hardware.
But as long as each node follows a set of rules or a network protocols, it can communicate with other
nodes on the network.
So to communicate correctly, all the nodes on a network must understand the same network protocols.
Here.
Let's actually, I just.
Here.
So and this is the functions and the what the network protocols serves in our network here.
So, uh, the network protocols serves many functions, including one of these functions here.
So this is the maintaining state session state.
So this protocols typically implement mechanisms to create a new connections and terminate existing
connections.
Here we, uh, this protocol also does identifying nodes through addressing here.
So data must be transmitted to correct node on a network.
So some protocols implement an addressing mechanism to identify specific nodes or groups of nodes.
And we are also going to control the flow.
So controlling flow.
So this is the amount of data transferred across a network is limited, of course, So the protocols
can implement ways of managing data flow to increase throughput and reduce latency.
And we are also going to be guaranteeing the order of transmitted data.
So many networks do not guarantee that the order in which the data is sent will match the order in which
it is received, and the protocol can reorder the data to ensure it's delivered in the correct order.
And we are also going to detecting and correcting errors here.
So.
Um, the many networks are not 100% reliable, right?
So data can become corrupted and it's important to detect the corruption and ideally correct it.
And here lastly, uh, formatting and encoding data and the data isn't always in a format suitable for
transmitting on a network.
And a protocol can specify ways of encoding data such as encoding English text into binary values.