Still using the RFC 2616 as reference for the HTTP/1.1 protocol? It’s more than time to stop! Seriously, forget it. It’s not relevant anymore.
I usually answer questions about HTTP on Stack Overflow and I’m surprised on how many developers still quote and use the old RFC 2616 as reference nowadays.
The HTTP/1.1 specification was inittially defined in the RFC 2068, released in January 1997. Improvements and updates to the HTTP/1.1 specification were released under the RFC 2616 in June 1999. In June 2014 the RFC 2616 was obsoleted for a whole new set of RFCs that collectively form the HTTP/1.1 specification:
- RFC 7230: HTTP/1.1: Message Syntax and Routing
- RFC 7231: HTTP/1.1: Semantics and Content
- RFC 7232: HTTP/1.1: Conditional Requests
- RFC 7233: HTTP/1.1: Range Requests
- RFC 7234: HTTP/1.1: Caching
- RFC 7235: HTTP/1.1: Authentication
These are the RFCs you must use as reference for the HTTP/1.1 protocol.