1. A method for identifying a cell that provides a differentiated service in a mobile communication system, the method comprising the steps of: searching for a plurality of pilots having a strength greater than a minimum pilot strength; comparing strengths of the pilots, and designating a pilot having the greatest strength as an active pilot; determining whether a corresponding cell of the active pilot transmits a cell classifier for the differentiated service along with an overhead message; if the corresponding cell transmits a cell classifier, determining whether the cell classifier matches a cell classifier stored in an access terminal; and if the cell classifier matches with a cell classifier stored in the access terminal, performing an operation under the control of the corresponding cell.