Classless Inter-domain Routing (CIDR): The Internet Address Assignment and Aggregation Plan
This specification has been revised 2 times since RFC 1338 (1992). Each document below formally obsoleted the one before it; the versions still in force are listed first.
Revision timeline
Current version — implement against this
Superseded versions — historical reference only
This lineage is derived automatically from the “obsoletes” relationships recorded in the public RFC Editor index — no editorial judgement is applied to the ordering. The most recent document in the chain is RFC 4632 (August 2006).