Network Resources
- Institute of Electrical and Electronics Engineers (IEEE) - Standards body responsible for many of the physical and data link layers
- Internet Engineering Task Force (IETF) - Protocol RFCs
- PacketLife - Ran by a fellow named Stretch. Great place to find detailed protocol "cheat sheets" and other good information.
- SC Labs -Study site compiled by someone looking to advance their certification. Material covers the older CCNP 642 exams, but the information is still relevant.
- Jeff Kronlage's CCIE Study Blog
Utilities
- 3CDaemon - Great windows tool for quick a FTP/TFTP/Syslog server
