19.6 Additional Features

This appendix documents protocol elements used by some existing HTTP implementations, but not consistently and correctly across most HTTP/1.1 applications. Implementers should be aware of these features, but cannot rely upon their presence in, or interoperability with, other HTTP/1.1 applications. Some of these describe proposed experimental features, and some describe features that experimental deployment found lacking that are now addressed in the base HTTP/1.1 specification.

• 19.6.1 Additional Request Methods
  • 19.6.1.1 PATCH
  • 19.6.1.2 LINK
  • 19.6.1.3 UNLINK
• 19.6.2 Additional Header Field Definitions
  • 19.6.2.1 Alternates
  • 19.6.2.2 Content-Version
  • 19.6.2.3 Derived-From
  • 19.6.2.4 Link
  • 19.6.2.5 URI