Chapter 1. Networking Overview
IP, TCP, and UDP Operations
This book assumes that the reader is already familiar with basic IP, TCP, and UCP operations; their header structures; and IPv4 addressing. This section briefly discusses some additional points about these protocols.
Packet fragmentation is handled differently in IPv4 and IPv6. Each link has a maximum transmission unit (MTU) size associated with it. If the IPv4 packet is larger than the interface MTU, it is fragmented (unless the Don’t Fragment bit is set in the IP header, in which case it will be dropped). Fragments of the same original packets are marked identically in the Identifier field of the IP header, so that the receiving router knows they belong together. The ...