Benefits and lacks of classical three-tier architecture in comparison to file-server architecture are investigated for the task of refactoring of existed information system. When they have an information system that has been based by historical reasons on file-server architecture and there are lot of diversity overpatching requirements then file-server architecture specific problems arisen. An example of such an information system is given.
Solution proposed is based on three-tier architecture. It contains such realization of an application tier that allows one to use almost all benefits related to the three-tier architecture and substantially neglect it’s disadvantages. There are also discussed some more benefits related to proposed architecture that are not linked directly to the sample information system.