Both digit strings encode decimal integers.  The
                   first integer indicates the count of uses of the
                   cache entry since the last report; the second integer
                   indicates the count of reuses of the entry.

   Section 5.3 specifies the counting rules.

   The meaning of the meter-response-directives are as follows:

   max-uses "=" 1*DIGIT
                   sets an upper limit on the number of "uses" of the
                   response, not counting its immediate forwarding to
                   the requesting end-client, for all proxies in the
                   following subtree taken together.

   max-reuses "=" 1*DIGIT
                   sets an upper limit on the number of "reuses" of the
                   response for all proxies in the following subtree
                   taken together.

   do-report       specifies that the proxy MUST send usage reports to
                   the server.

   dont-report     specifies that the proxy SHOULD NOT send usage
                   reports to the server.

   timeout "=" 1*DIGIT
                   sets a metering timeout of the specified number of
                   minutes (not seconds) after the origination of this
                   response (as indicated by its "Date" header).  If the




 
RFC 2227            Hit-Metering and Usage-Limiting         October 1997


                   proxy has a non-zero hit count for this response when
                   the timeout expires, it MUST send a report to the
                   server at or before that time.  Timeouts should be
                   implemented with an accuracy of plus or minus one
                   minute.  Implies "do-report".

   wont-ask        specifies that the proxy SHOULD NOT send any Meter
                   headers to the server.  The proxy should forget this
                   advice after a period of no more than 24 hours.

   Section 5.3 specifies the counting rules, and in particular specifies
   a somewhat non-obvious interpretation of the max-uses value.

5.2 Abbreviations for Meter directives

   To allow for the most efficient possible encoding of Meter headers,
   we define abbreviated forms of all Meter directives.  These are
   exactly semantically equivalent to their non-abbreviated
   counterparts.  All systems implementing the Meter header MUST
   implement both the abbreviated and non-abbreviated forms.
   Implementations SHOULD use the abbreviated forms in normal use.

   The abbreviated forms of Meter directive are shown below, with the
   corresponding non-abbreviated literals in the comments:

       Abb-Meter = "Meter" ":" 0#abb-meter-directive

       abb-meter-directive = abb-meter-request-directive
                       | abb-meter-response-directive
                       | abb-meter-report-directive

       abb-meter-request-directive =
                         "w"           ; "will-report-and-limit"
                       | "x"           ; "wont-report"
                       | "y"           ; "wont-limit"

       abb-meter-report-directive =
                       | "c" "=" 1*DIGIT "/" 1*DIGIT   ; "count"

       abb-meter-response-directive =
                         "u" "=" 1*DIGIT       ; "max-uses"
                       | "r" "=" 1*DIGIT       ; "max-reuses"
                       | "d"                   ; "do-report"
                       | "e"                   ; "dont-report"
                       | "t" "=" 1*DIGIT       ; "timeout"
                       | "n"                   ; "wont-ask"






 
RFC 2227            Hit-Metering and Usage-Limiting         October 1997


      Note: although the Abb-Meter BNF rule is defined separately from
      the Meter rule, one may freely mix abbreviated and non-abbreviated
      Meter directives in the same header.

5.3 Counting rules