9.5  Server Error 5xx ..................................... 37
   10. Header Field Definitions .................................. 37
       10.1  Allow ............................................... 38
       10.2  Authorization ....................................... 38
       10.3  Content-Encoding .................................... 39
       10.4  Content-Length ...................................... 39
       10.5  Content-Type ........................................ 40
       10.6  Date ................................................ 40
       10.7  Expires ............................................. 41
       10.8  From ................................................ 42




 
RFC 1945                        HTTP/1.0                        May 1996


       10.9  If-Modified-Since ................................... 42
       10.10 Last-Modified ....................................... 43
       10.11 Location ............................................ 44
       10.12 Pragma .............................................. 44
       10.13 Referer ............................................. 44
       10.14 Server .............................................. 45
       10.15 User-Agent .......................................... 46
       10.16 WWW-Authenticate .................................... 46
   11. Access Authentication ..................................... 47
       11.1  Basic Authentication Scheme ......................... 48
   12. Security Considerations ................................... 49
       12.1  Authentication of Clients ........................... 49
       12.2  Safe Methods ........................................ 49
       12.3  Abuse of Server Log Information ..................... 50
       12.4  Transfer of Sensitive Information ................... 50
       12.5  Attacks Based On File and Path Names ................ 51
   13. Acknowledgments ........................................... 51
   14. References ................................................ 52
   15. Authors' Addresses ........................................ 54
   Appendix A.   Internet Media Type message/http ................ 55
   Appendix B.   Tolerant Applications ........................... 55
   Appendix C.   Relationship to MIME ............................ 56
       C.1  Conversion to Canonical Form ......................... 56
       C.2  Conversion of Date Formats ........................... 57
       C.3  Introduction of Content-Encoding ..................... 57
       C.4  No Content-Transfer-Encoding ......................... 57
       C.5  HTTP Header Fields in Multipart Body-Parts ........... 57
   Appendix D.   Additional Features ............................. 57
       D.1  Additional Request Methods ........................... 58
            D.1.1  PUT ........................................... 58
            D.1.2  DELETE ........................................ 58
            D.1.3  LINK .......................................... 58
            D.1.4  UNLINK ........................................ 58
       D.2  Additional Header Field Definitions .................. 58
            D.2.1  Accept ........................................ 58
            D.2.2  Accept-Charset ................................ 59
            D.2.3  Accept-Encoding ............................... 59
            D.2.4  Accept-Language ............................... 59
            D.2.5  Content-Language .............................. 59
            D.2.6  Link .......................................... 59
            D.2.7  MIME-Version .................................. 59
            D.2.8  Retry-After ................................... 60
            D.2.9  Title ......................................... 60
            D.2.10 URI ........................................... 60








 
RFC 1945                        HTTP/1.0                        May 1996


1.  Introduction

1.1  Purpose

   The Hypertext Transfer Protocol (HTTP) is an application-level
   protocol with the lightness and speed necessary for distributed,
   collaborative, hypermedia information systems. HTTP has been in use
   by the World-Wide Web global information initiative since 1990. This
   specification reflects common usage of the protocol referred too as
   "HTTP/1.0". This specification describes the features that seem to be
   consistently implemented in most HTTP/1.0 clients and servers. The
   specification is split into two sections. Those features of HTTP for
   which implementations are usually consistent are described in the
   main body of this document. Those features which have few or
   inconsistent implementations are listed in Appendix D.

   Practical information systems require more functionality than simple
   retrieval, including search, front-end update, and annotation. HTTP
   allows an open-ended set of methods to be used to indicate the
   purpose of a request. It builds on the discipline of reference
   provided by the Uniform Resource Identifier (URI) [2], as a location
   (URL) [4] or name (URN) [16], for indicating the resource on which a
   method is to be applied. Messages are passed in a format similar to
   that used by Internet Mail [7] and the Multipurpose Internet Mail
   Extensions (MIME) [5].