Testing and Quality Assurance
ASPs must maintain a separate testing environment to "test drive" hosted applications loaded with your data on a computing platform like the one it has sized and configured for you. The test environment is like a Y2K platform where, after an upgrade, applications are test run to see if they are Y2K compliant. Most test environments are fairly standardized, not customized literally to replicate the hardware and other equipment of each new customer. For instance, if you lease an application for 200 users, the ASP can create a simulation environment with 200 "logical" seats, not actual PCs.
However, the ASP does use the testing platform to configure and customize the actual hosted application, as explained earlier, and then to run it through various user scenarios to see if it can hold up to the performance guarantees of each customer's SLA. The test driving is generally what's considered "testing."