fsegment       = 1*pchar
          segment        = *pchar

          params         = param *( ";" param )
          param          = *( pchar | "/" )





 
RFC 2068                        HTTP/1.1                    January 1997


          scheme         = 1*( ALPHA | DIGIT | "+" | "-" | "." )
          net_loc        = *( pchar | ";" | "?" )

          query          = *( uchar | reserved )
          fragment       = *( uchar | reserved )

          pchar          = uchar | ":" | "@" | "&" | "=" | "+"
          uchar          = unreserved | escape
          unreserved     = ALPHA | DIGIT | safe | extra | national

          escape         = "%" HEX HEX
          reserved       = ";" | "/" | "?" | ":" | "@" | "&" | "=" | "+"
          extra          = "!" | "*" | "'" | "(" | ")" | ","
          safe           = "$" | "-" | "_" | "."
          unsafe         = CTL | SP | <"> | "#" | "%" | "<" | ">"
          national       = <any OCTET excluding ALPHA, DIGIT,
                           reserved, extra, safe, and unsafe>

   For definitive information on URL syntax and semantics, see RFC 1738
   [4] and RFC 1808 [11]. The BNF above includes national characters not
   allowed in valid URLs as specified by RFC 1738, since HTTP servers
   are not restricted in the set of unreserved characters allowed to
   represent the rel_path part of addresses, and HTTP proxies may
   receive requests for URIs not defined by RFC 1738.

   The HTTP protocol does not place any a priori limit on the length of
   a URI. Servers MUST be able to handle the URI of any resource they
   serve, and SHOULD be able to handle URIs of unbounded length if they
   provide GET-based forms that could generate such URIs. A server
   SHOULD return 414 (Request-URI Too Long) status if a URI is longer
   than the server can handle (see section 10.4.15).

     Note: Servers should be cautious about depending on URI lengths
     above 255 bytes, because some older client or proxy implementations
     may not properly support these lengths.

3.2.2 http URL

   The "http" scheme is used to locate network resources via the HTTP
   protocol. This section defines the scheme-specific syntax and
   semantics for http URLs.











 
RFC 2068                        HTTP/1.1                    January 1997


          http_URL       = "http:" "//" host [ ":" port ] [ abs_path ]

          host           = <A legal Internet host domain name
                            or IP address (in dotted-decimal form),
                            as defined by Section 2.1 of RFC 1123>

          port           = *DIGIT

   If the port is empty or not given, port 80 is assumed. The semantics
   are that the identified resource is located at the server listening
   for TCP connections on that port of that host, and the Request-URI
   for the resource is abs_path. The use of IP addresses in URL's SHOULD
   be avoided whenever possible (see RFC 1900 [24]). If the abs_path is
   not present in the URL, it MUST be given as "/" when used as a
   Request-URI for a resource (section 5.1.2).

3.2.3 URI Comparison

   When comparing two URIs to decide if they match or not, a client
   SHOULD use a case-sensitive octet-by-octet comparison of the entire
   URIs, with these exceptions:

     o  A port that is empty or not given is equivalent to the default
        port for that URI;

     o  Comparisons of host names MUST be case-insensitive;

     o  Comparisons of scheme names MUST be case-insensitive;

     o  An empty abs_path is equivalent to an abs_path of "/".