The Internet Report (IETF Weekly Updates) - A table of new Internet Drafts and RFC's that come out each week, with synopses. Archived summaries go back to June 1999.
RFC Editor - Collates Request For Comments documents. Explains the RFC process, and includes a searchable database of RFCs.
A consortium led by universities working in partnership with industry and government to develop and deploy advanced network applications and technologies, accelerating the creation of tomorrow's Internet.
General comments on protocol design, and good reference material on a few protocols (especially mail-related; also ftp, time, and misc) by Dan Bernstein.
A protocol that transfers text and binary files without errors between diverse types of computers over potentially hostile communication links, and a suite of communications software programs; Columbia University.
Independent organization managing the eXtensible Name Service, an open protocol and open-source platform for universal addressing, automated data exchange, and privacy control. Includes an overview, charter, history, and specifications.