Proxy-Authenticate

Proxy-Authenticate

The Proxy-Authenticate header functions like the WWW-Authenticate header. It is used by proxies to challenge an application sending a request to authenticate itself. The full details of this challenge/response, and other security mechanisms of HTTP, are discussed in detail in Chapter 14.

If an HTTP/1.1 proxy server is sending a 407 Proxy Authentication Required response, it must include the Proxy-Authenticate header.

Proxies and gateways must be careful in interpreting all the Proxy headers. They generally are hop-by-hop headers, applying only to the current connection. For instance, the Proxy-Authenticate header requests authentication for the current connection.