Please refer to the Ethernet page for more up to date information. This page is ancient and some love could be used to organize this information a little better under the ethernet section
This information is based off of personal experience and/or information gleaned from the web and mailing lists. It is not necessarily 100% accurate. Corrections are welcome.
Q: Why can I ping an IP address when the interface is down?
A: Linux uses a "host based" addressing model, IP addresses are owned by the host, not individual interfaces. So as long as the IP address is configured to some interface, we will accept packets destinated to that IP address as our's.
A collection of programs that form the base set of the NET-3 networking distribution for the Linux operating system. This package includes arp(8), hostname(1), ifconfig(8), ipmaddr, iptunnel, mii-tool(8), nameif(8), netstat(8), plipconfig(8), rarp(8), route(8) and slattach(8).
The Spanning Tree Protocol (STP) is used to allow multiple bridges to work together. Each bridge communicates with other bridges to discover how they are interconnected. This information is then used to eliminate cycles, and provide optimal routing of packets. STP also provides fault tolerance, because it will recompute the topology if a bridge or port fails.