Mapping the TCP/IP and OSI Models

The TCP/IP suite of protocols works in Layers 3 and 4 of the OSI model. TCP/IP is made up of two protocols: TCP and IP. TCP/IP is the protocol used for communication over the Internet. Besides working in Layers 3 and 4, TCP/IP also has specifications for applications such as mail and FTP. Figure 1.7 depicts the mapping of the OSI and TCP/IP models.

Figure 1.7: Mapping the OSI and TCP/IP models.