A 2.1.5 TCP/IP (HL only)
The TCP/IP model describes how data is carried across a network by dividing the job into four layers, each with its own responsibility. Splitting the work this way means each layer can do one thing well and rely on the layers below it, and it lets devices from different manufacturers communicate as long as they follow the same rules. This page describes the four layers, the application, transport, internet and...