enables self - serving consumer to indicate personal element of demand for a particular product so they are alerted to modified supply for the product . potential buyers use input in the form of mms protocol or sms protocol to communicate a proprietary code to a communications host . the store and product information , together with a return address for responsive communications concerning the product , is stored in a third - party database . a seller interested in demand in their establishment could access the database and retrieve aggregate buyer - segmented product demand information for the consumer they target . the seller could effectively design incentive schemes and communicate promotional information by sms protocol to the potential buyer via the communications host . the system is highly targeted , enhances economic communication of unsatisfied demand and delivers promotional supply information to self - targeted consumers with protection from unsolicited seller spam .