What is the TCP/IP reference model? Can you describe its layers?

As with any question addressing a reference model or an item with several components, your answer should be in the form of a list. Each technology element should be listed and include a brief description of its function. Make sure to keep your answer brief and to the point and anticipate a follow-up question from the interviewer.

"The TCP/IP reference model is a compressed version of the OSI model. It only contains four layers and is based on the two protocols used to transmit data developed by the U.S. government during the 1980s. These are the Transmission Control Protocol or TCP and Internet Protocol, also known as IP. The four layers of the TPC/IP protocol are Applications, Transport, Internet, and Link. The application layer contains standards such as HTTP, SMTP, and DNS. The transport layer consists of TCP and UDP protocols. The internet layer includes IP and ICMP protocols. Link, which is the final layer, has protocols such as DSL, Ethernet, and the 802.11 wireless protocol."