TCP/IP and the DoD Model

The figure shows a comparison of the DoD model and the OSI reference model. As you can see, the two are similar in concept, but each has a different number of layers with different names.


The TCP/IP Protocol Suite


The DoD and OSI models are alike in design and concept and have similar functions in similar layers.


Process/Application Layer

This section describes different applications and services typically used in IP networks. The following protocols and applications are discussed:

• Telnet
• FTP
• TFTP
• NFS
• SMTP
• LPD
• X Window
• SNMP
• DNS
• DHCP/BootP