When a user requests to view a report using ePortfolio, the request is passed from the web server to the Web Connector. The Web Connector handles all Crystal Enterprise requests that are made to the web server. The Web Connector then passes the request to the Web Component Server (WCS), which communicates with the rest of Crystal Enterprise. Since the request was to view a report, the WCS passes the request to the Cache Server.
The Cache Server checks to see if it has the requested pages cached. The cached pages are stored as Encapsulated Page Format (.epf) files. If a cached version of the .epf file is available, the Cache Server checks with the Automated Process Scheduler (APS) to see if the user has rights to view the report. If the user is granted the right to view the report, the Cache Server sends the .epf file to the WCS.
If a cached version of the .epf file is unavailable, the Cache Server requests new .epf files from the Page Server. The Page Server retrieves the report from the Input File Repository Server, first checking with the APS to see if the user has rights to view the report.
Note: If the user is granted View rights to the report object, then the Page Server will only ever generate pages of the latest report instance. That is, the Page Server will not retrieve the latest data from the database. If, however, the user is granted View On Demand rights to the report object, then the Page Server will refresh the report against the database.
If the user has sufficient rights, the Page Server generates the .epf pages and forwards them to the Cache Server. The Cache Server then caches the .epf files and sends them to the WCS.
Once the WCS receives the cached or generated .epf files from the Cache Server, it forwards the pages through the Web Connector to the user's web browser. (If the user is using the DHTML Viewer, the WCS first converts the .epf file to an HTML page.)
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