Web Caching and Replication

1.3. Overview of Internet Protocols

This section provides an overview of the commercially successful rival of the ISO/OSI model: the Internet that was standardized in the 1980s. The availability of the Internet protocols at this early stage resulted in their adoption and the rise of the Internet. Figure 1.2 depicts a selection of Internet protocols commonly found on Internet hosts. The figure also highlights the fact that the Internet does not readily map to the OSI seven layers. Some of the layers separated in the OSI model are combined in the Internet. The following layers are usually distinguished in the Internet:

Figure 1.2. Common protocols in the Internet

The physical layer: The Internet physical layer typically combines the physical and ...