When a spreadsheet is incorporated into an EASAP, it is not displayed directly to the end users in the user interface of the EASAP. Instead, the Excel file is opened in Excel in an automated way by EASA on an Excel Server, which is remote from the users. A user’s access to the spreadsheet is controlled by the user interface of the EASAP, which is displayed in a web browser. See the figure below for a diagram of the EASA architecture showing the connection from users’ computers to the EASA Server and on to Excel Servers.
Since the spreadsheet is not rendered directly in the web browser interface of the EASAP, an Author can control how data contained in the spreadsheet is displayed and modified in the user interface. Here are some of the key choices to be made when designing the EASAP’s user interface: