The network layer (layer 3) is the layer that coordinates the transmission of data to other networks (that is, outside of the user's own network). This is particularly important to the cybersecurity analyst because it is this network that informs you whether the threat is internal or external, and therefore allows the operations center to focus its attention on preventing access or segmenting the network.
In this section, we will learn how to describe the fields in network layer packet headers and how they can betray an intrusion. Ensure that you know the difference between the addresses at layer 2 and the addresses at layer 3.
The network layer contains routing information – the addresses identify the device requesting the information, and the resource on which it is held. Where the MAC addresses at layer 2 describe...