Several Implementation Solutions for wireless POS

With the development of network technology and e-commerce, wireless applications in the financial industry have also developed. Commercial banks have successively launched applications such as wireless transaction and wireless electronic payment. As an important implementation method, wireless POS is widely used in the wireless payment field. It also has a wide range of implementation solutions, which are described as follows:

1. cdpd Mode
Cdpd (Cellular Digital Packet Data
Cellular Digital Packet Data Transmission System (DTS) is a transmission technology based on TCP/IP, between analog transmission and digital transmission, it can make full use of the simulated transmission infrastructure eliminated by telecom companies,
The establishment of a unified public wireless data transmission network is currently in the construction phase, there are many non-technical uncertainties, implementation cases are not very rich.

2. GSM Short Message Mode
GSM (Global System
Mobile, Global Mobile Communication System) technology is currently the mainstream support protocol for various mobile communication companies in China, so there are many implementation solutions.

The SMS center of mobile communication companies usually has service interfaces through which users can transmit data, such as Mt (Sending Short Messages) and Mo (receiving short messages ).
Message entity, short message entity) technology.
For an SME instance, you can apply for an ID number through which the SMS center can determine whether a mo message should be sent via a wireless system or through an interface to SME, that is, the routing may be different, thus implementing the SME storage forwarding function.
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Because the maximum length of a short message is 140 bytes, the packets sent from the POs are not the bank's 8583 standard packets. In this way, the network controller cannot be used as the access device of the bank.
A wireless POS front-end machine is set as the SME on the row end. This front-end machine converts the data received or sent from the SMS center to the Financial Transaction format, and then forwards the data to the downstream card of the network controller or directly forwards the data to the bank pos.
The system then converts the returned data from the bank into the text message data format and transmits the data to the wireless POS through the SMS center to implement a complete bank transaction.

The main disadvantage of this solution is the non-real-time messaging, which is sometimes fatal.

Topology 1 of the short message mode is shown in.

3. GSM dialing Mode
Compared with the GSM text message technology, directly using the GSM data transmission channel may be the most direct method. At the bank's access end, we can achieve this through the transformation of NAC or through the wireless POS front-end machine.

The method for transforming NAC is as follows: NAC is still connected to the front-end server through Ethernet or serial port, while POS must support GSM and install SIM cards or STK cards that support bidirectional data transmission. Same
The downlink cards of the original network controller are divided into two groups: wired POs and wireless POS applications, while the uplink cards remain unchanged. Because the traditional downlink card only supports the synchronization protocol and the GSM protocol only supports asynchronous data streams
To develop new businesses, we need to replace the downlink card chips used by wireless POS on the network controller to support asynchronous communication and transmission protocols. This downlink cartoon has an external asynchronous modem and PSTN (telephone
Network) to receive requests from wireless POS over the GSM network.

String 3

In this solution, the bank's pos pre-system program does not need to be modified. The original wired POS application is not affected. The wireless POS application only needs to modify the communication mode based on the original wired POS application software, the implementation of the solution is smooth and operable. There are currently many successful implementation cases.

The topology 2 of the GSM dialing communication mode is shown in.
In addition to the GSM Short Message mode, each access mode of the wireless POS can be divided into two modes: The frontend server and the network controller. Through the frontend server, the frontend server is set up to asynchronously adjust the POs packets.
After the modem is connected, the TCP/IP socket technology can be directly forwarded to the POs front-end system of the bank. Of course, it can also be forwarded to the downlink card of the network controller. This article uses GSM dial-up communication as an example to describe (
3.

4. GPRS Mode
GPRS (General Packet Radio System
Is a next-generation communication protocol platform launched by China Mobile. How to develop new businesses on this platform is a new topic for hardware vendors and customers.

For our wireless business applications, the main advantage of GPRS is always online, fast login, and high-speed transmission. This is to overcome the disadvantages of low chain building speed and low transmission rate in GSM mode, excellent
. Taking the wireless POS application as an example, once the machine is started, it establishes a connection with the GPRS network. In the future, POS transactions only require 1 ~ 3 seconds of activation, saving
10 ~ The leeching time in 20 seconds. Similarly, theoretically, the transmission rate of more than 100 kbit/s is also important to shorten the transaction time.

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In terms of network connection, the GPRS system supports connecting nodes ggsn and sgsn to the target network through the network. The destination network can be an Internet network or X.25 network,
This means that the Bank access method in this mode can be IP address or X.25, as shown in solution 4.

We can see that GPRS has overcome the main disadvantages of low bandwidth and low stability of dial-up transmission in the past, and also supports multiple flexible device access methods, such as Ethernet and serial ports, these advantages allow this model to be extended
Other wireless applications, such as wireless POS, have broad application prospects if they can negotiate a reasonable fee level with communications companies or even act as the main communication mode for online transactions.