Chapter 7 Web cache configuration 219Using the BayStack Instant Internet Management Software Version 7.11Setting options for special Web requestsSpecial Web requests contain more than HTML-based Web content. These specialrequests usually require user interaction or input and could contain private orpersonalized information. The Instant Internet unit has several options formaximizing Web content cacheability while minimizing the return of sensitiveinformation. There are three types of special Web requests: CGI, query, and“no-cache” requests. Statistics are available on the Web Cache Statistics page tohelp you decide whether to enable these requests.CGI requestsA CGI (Common Gateway Interface) program is an application that runs on theoriginating Web server and is designed to accept input from and return data to auser. An example of this type of request is a request where you enter informationin a form and receive other information in return. You can select whether toretrieve the same CGI requests from the cache or from the originating Web server.If you select to retrieve the same CGI requests from the cache and two users use aCGI program to request the same information from the same Web server and theresults are the same, the results are sent from the cache rather than the originatingWeb server.To determine whether you may need to enable CGI requests, look at the statisticfor “CGI request” in the “Why requests are not served from the cache” area. If thisnumber is high (over 10%), you should enable the option to retrieve CGI requestsfrom the cache. This option is enabled by default for the Moderate Aggressivecache levels.Query requestsYou can select whether to retrieve the same query requests (for example, to asearch engine) from the cache or from the originating Web server.For example, if you select to retrieve the same query requests from the cache andtwo users perform a search for “Shakespeare’s sonnets” using the same searchengine and the results are the same, the results are sent from the cache rather thanthe originating Web server.
