Bandwidth Table

ICMP Type Codes

List of codes used on 802.3 and Ethernet networks

Ethernet Type Codes

Vendor Codes

Multicast (including Broadcast) Addresses

Subnet Cheat Sheet

Netmasks Expanded

Understanding the OSI 7 Layer Model (PDF)

3Com school wiring guide (PDF)

SANS TCP/IP and TCPDump Pocket Reference Guide (PDF)