# Introduction

### Purpose

This is a integration system protocol between Cashier Terminal and Backend system.

To enable the Cashier Terminal and [e-Buy backend](https://book.e-buy.com/link/124#bkmrk-e-buy-backend "A group /set of equipment / server to process all the transaction from e-Buy POS") payment and redemption business real-time transaction process and synchronization, reduce reconciliation errors, facilitate business transaction in real-time integration to [e-Buy backend](https://book.e-buy.com/link/124#bkmrk-e-buy-backend "A group /set of equipment / server to process all the transaction from e-Buy POS") system, in order to support multiple business transaction demand, such as multiple payment method and redemption method.

### Physical Architecture

![Network](http://portal.e-buychina.com.cn/doc/Public/Uploads/2017-04-08/58e8f27eb9497.png "Network")

**Network illustration：**

- 1.Cashier POS and [MIS-POS](https://book.e-buy.com/link/124#bkmrk-mis-pos "Installed in merchants in-store POS machine, providing the operation activity to support and exchange function") integration is thru USB port or serial port, each Cashier Terminalis thru network connection.
- 2.Each store (include 1 or more cashier POS) is connected thru Public VPN back to [e-Buy Backend](https://book.e-buy.com/link/124#bkmrk-e-buy-backend "A group /set of equipment / server to process all the transaction from e-Buy POS").
- 3.[e-Buy Backend](https://book.e-buy.com/link/124#bkmrk-e-buy-backend "A group /set of equipment / server to process all the transaction from e-Buy POS") is connected to each Credit card banking system thru leased line.

### Logic Architecture

![Middleware](http://portal.e-buychina.com.cn/doc/Public/Uploads/2017-04-08/58e8f6628b1df.png "Middleware")

**Flow illustration:**

- 1.Cashier POS initiates the payment transaction, including the related transaction information to push to the [e-Buy Backend](https://book.e-buy.com/link/124#bkmrk-e-buy-backend "A group /set of equipment / server to process all the transaction from e-Buy POS").
- 2.[e-Buy Backend](https://book.e-buy.com/link/124#bkmrk-e-buy-backend "A group /set of equipment / server to process all the transaction from e-Buy POS") will process as per type of transaction provided. If required, corresponding data will send to the Card Issued Organization to process accordingly. At final, will return back the result to the Cashier POS.