Internet Protocol

First, the foundations. The Internet Protocol provides a universal long-distance delivery mechanism on the third layer of the OSI model. It contains a set of parameters that were meant to be interpreted and eventually modified by intermediate systems. The header is shown in Figure 9-3.

The IP header structure

Figure 9-3. The IP header structure

Protocol Version

This is a four-bit value that is fixed to 4 (0100) in all IPv4 packets. IPv4 is the standard (and, in many cases, the only supported) layer three protocol over the Internet. Attempts to move toward a more advanced implementation, IPv6, have not been particularly successful so far—the author is willing ...

Get Silence on the Wire now with the O’Reilly learning platform.

O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers.