Routine Maintenance and Upgrades
As a fundamental tenet of the ASP business proposition, most maintenance and upgrades are included with the leased application. How much of the cost for these activities is included in the leasing fee and how much is a billable service depends on the ASP. Some ASPs may charge a premium for especially redundant backup or for extra storage, for example. As a rule of thumb, though, these activities come part-and-parcel with the hosted service.
You should also expect certain key upgrade activities to be covered by the maintenance/upgrade agreement, have input on the date of upgrades, and expect the ASP to take sufficient change management measures to ensure the upgrades do not unsatisfactorily interrupt work. The ASP should routinely upgrade, either remotely or on-site, needed client software as well as the operating systems on the servers in the data center. It should also locate and install or develop patches for all software bugs in its vendor's software. (If the ASP has an equity relationship with the vendor, the vendor is likely to be more responsive in creating patches.) The ASP should also keep at your reasonable disposal a database administrator certified on the databases used by the hosted application.
Of course, the ASP should also routinely backup, restore, and archive data. The media on which data is stored is determined in the SLA, but most ASPs will back up data each night and store an extra copy on tape off-site. Some may offer less frequent backup intervals for lower fees.