- 1) Introduction
- 2) Notational Conventions and Generic Grammar
- 3) Protocol Parameters
- 4) HTTP Message
- 5) Request
- 6) Response
- 7) Entity
- 8) Connections
- 9) Method Definitions
- 10) Status Code Definitions
- 1) Informational 1xx
- 2) Successful 2xx
- 3) Redirection 3xx
- 4) Client Error 4xx
- 1) 400 Bad Request
- 2) 401 Unauthorized
- 3) 402 Payment Required
- 4) 403 Forbidden
- 5) 404 Not Found
- 6) 405 Method Not Allowed
- 7) 406 Not Acceptable
- 8) 407 Proxy Authentication Required
- 9) 408 Request Timeout
- 10) 409 Conflict
- 11) 410 Gone
- 12) 411 Length Required
- 13) 412 Precondition Failed
- 14) 413 Request Entity Too Large
- 15) 414 Request-URI Too Long
- 16) 415 Unsupported Media Type
- 17) 416 Requested Range Not Satisfiable
- 18) 417 Expectation Failed
- 5) Server Error 5xx
- 11) Access Authentication
- 12) Content Negotiation
- 13) Caching in HTTP
- 1) ..
- 2) Expiration Model
- 3) Validation Model
- 4) Response Cacheability
- 5) Constructing Responses From Caches
- 6) Caching Negotiated Responses
- 7) Shared and Non-Shared Caches
- 8) Errors or Incomplete Response Cache Behavior
- 9) Side Effects of GET and HEAD
- 10) Invalidation After Updates or Deletions
- 11) Write-Through Mandatory
- 12) Cache Replacement
- 13) History Lists
- 14) Header Field Definitions
- 1) Accept
- 2) Accept-Charset
- 3) Accept-Encoding
- 4) Accept-Language
- 5) Accept-Ranges
- 6) Age
- 7) Allow
- 8) Authorization
- 9) Cache-Control
- 10) Connection
- 11) Content-Encoding
- 12) Content-Language
- 13) Content-Length
- 14) Content-Location
- 15) Content-MD5
- 16) Content-Range
- 17) Content-Type
- 18) Date
- 19) ETag
- 20) Expect
- 21) Expires
- 22) From
- 23) Host
- 24) If-Match
- 25) If-Modified-Since
- 26) If-None-Match
- 27) If-Range
- 28) If-Unmodified-Since
- 29) Last-Modified
- 30) Location
- 31) Max-Forwards
- 32) Pragma
- 33) Proxy-Authenticate
- 34) Proxy-Authorization
- 35) Range
- 36) Referer
- 37) Retry-After
- 38) Server
- 39) TE
- 40) Trailer
- 41) Transfer-Encoding
- 42) Upgrade
- 43) User-Agent
- 44) Vary
- 45) Via
- 46) Warning
- 47) WWW-Authenticate
- 15) Security Considerations
- 16) Acknowledgments
- 17) References
- 18) Authors' Addresses
- 19) Appendices
- 20) Index
- 21) Full Copyright Statement
- 22) Acknowledgement
14.33 Proxy-Authenticate
The Proxy-Authenticate response-header field MUST be included as part of a 407 (Proxy Authentication Required) response. The field value consists of a challenge that indicates the authentication scheme and parameters applicable to the proxy for this Request-URI.
Proxy-Authenticate = "Proxy-Authenticate" ":" 1#challenge
The HTTP access authentication process is described in "HTTP Authentication: Basic and Digest Access Authentication" [43]. Unlike WWW-Authenticate, the Proxy-Authenticate header field applies only to the current connection and SHOULD NOT be passed on to downstream clients. However, an intermediate proxy might need to obtain its own credentials by requesting them from the downstream client, which in some circumstances will appear as if the proxy is forwarding the Proxy-Authenticate header field.