6.2 Response Header Fields


The response-header fields allow the server to pass additional information about the response which cannot be placed in the Status- Line. These header fields give information about the server and about further access to the resource identified by the Request-URI.
       response-header = Accept-Ranges           ; Section 14.5
                       | Age                     ; Section 14.6
                       | ETag                    ; Section 14.19
                       | Location                ; Section 14.30
                       | Proxy-Authenticate      ; Section 14.33
                       | Retry-After             ; Section 14.37
                       | Server                  ; Section 14.38
                       | Vary                    ; Section 14.44
                       | WWW-Authenticate        ; Section 14.47


Response-header field names can be extended reliably only in combination with a change in the protocol version. However, new or experimental header fields MAY be given the semantics of response- header fields if all parties in the communication recognize them to be response-header fields. Unrecognized header fields are treated as entity-header fields.