4447f991_P_Guide___HTTP_General_Headers__HTTP_Cache_Control_Directives_HTTP_Message_Type
[Cache-Control Directive] max-age [Description] In a request, indicates that the client is willing to accept a response whose age is no greater than the value specified. In a response, indicates the maximum age of the response before it is considered stalethis is an alternative to the use of the Expires header and takes precedence over it. [HTTP Message Type] 
Request or Response
R e q u e s t o r R e s p o n s e
R e s p o n s e
R e q u e s t
The TCP/IP Guide - HTTP General Headers
HTTP Message Type