POS (Point of Sales) real-time service system is the important base of realizing commercial automation.China's banks have set up their own systems of cable access to POS systems, but the cable POS machines are always restricted by space and telecommunication lines, which make it hard to achieve the goal that card consumption can be quick and checked at anytime and anyplace. The access way of GPRS wireless POS machines can solve the problem that POS machines can only be used on some fixed occasions, which makes POS machines not restricted by the telecommunication, and now it has been widely accepted by customers, such as, hotels, gas companies, bus companies, highway authorities, banks, distribution centers, passenger ticketing centers, taxation departments, delivery companies, and mobile sales offices, etc.