This document specifies additional HyperText Transfer Protocol
(HTTP) status codes for a variety of common situations, to improve
interoperability and avoid confusion when other, less precise status
codes are used.
This work has been completed outside the HTTPBIS WG because
the HTTPBIS charter was scoped tightly to avoid distractions, such
as new status codes.
Working Group Summary
This document is not the product of a working groups, although it
has been reviewed by participants in the HTTPBIS WG and
There has been some controversy about the practice of intercepting
proxies in HTTP, which caused the need for status code 511 ("Network
Authentication Required"). However, there is agreement that a code
is needed so that clients can react appropriately to requests for
authentication that they receive from intermediaries.
The document has been reviewed by participants in the HTTPBIS WG
and APPSAWG WG. It is deemed to be of good quality.
The status of implementation is unknown, however these codes are
are relatively straightforward to implement and deploy because they
are consistent with the default handling of 4xx and 5xx series codes
The Document Shepherd is Julian Reschke.
The Responsible Area Director is Peter Saint-Andre.