Packet analysis is all about analyzing how applications transfer useful data from point A to point B over networks. So, an understanding of how networks function is essential.
In this chapter, we will cover the following topics:
Why the seven-layer OSI model matters
IP networks and subnets
Switching and routing packets
Ethernet frames and switches
IP addresses and routers
WAN links
Wireless networking
The seven-layer OSI model will be mapped to the most common networking terms, and we'll review frames, switching, IP addressing, routing, and a few other networking topics of interest. The goal is to develop a mental model of networking that lends itself well to packet-level analysis.