Protocols.com 
Contains a comprehensive directory of some 200+ protocols with links to protocol standards and other protocol related Internet sites. Protocols listed include: ATM UNI, ATM signalling, Frame Relay, Ethernet, ISDN, PNNI, PPP, TCP/IP and many more.
IEEE Gigabit Ethernet Information
Working documents of the group developing the IEEE 802.3z Gigabit Ethernet standard.
Annotated Bibliography of MTU Related Publications
Links to publications, documents, and studies on MTU related topics.
Gigabit Ethernet Jumbo Frames, And why you should care
Jumbo frames extends ethernet to 9000 bytes. Why 9000? First because Ethernet uses a 32 bit CRC that loses its effectiveness above about 12000 bytes. And secondly, 9000 was large enough to carry an 8 KB application datagram (e.g. NFS) plus packet header overhead. Is 9000 bytes enough? It's a lot better than 1500, but for pure performance reasons there is little reason to stop there.
