A requirement arose where a small system was required that would allow people to complete an electronic survey at a show. There was no guarantee that there would be a reliable internet connection or 3G signal so a standalone setup was needed. Additionally the available power was limited so the loading needed to be restricted.

My solution was to configure a laptop as a web server with MySQL and running DHCP and DNS. This would run as the main server and power the actual survey along with collecting the results.

The screens that would be used for people to complete the survey were assembled using a regular 19" flatscreen monitor with DVI connection. A Raspberry Pi installed with a Raspberrian Linux operating system was then configured in an auto-boot 'web-kiosk' mode using Midori. Javascript prevented access to the function keys and right-mouse-button.

Using this configuration and the ability to clone the SD card of the Raspberry Pi has meant that it is possible to expand beyond the initial 2 entry screens for less than £150 per screen and have a low power overhead of around 350 watts.

The Red E-Till EPoS was developed after it was discovered that there were no specialist systems within the marketplace. The Red E-Till consists of a touchscreen computer running a bespoke till interface and a back-end web application tool centrally run within a virtualised web server.

The tills are developed to send and receive data over HTTPS using a Extended Validation SSL certificate which ensures no special configuration is required on-site. Should no internet connection be available for a period of time, the tills will run in an offline mode and hold all transactions for replication until such time as an internet connection be available. Due to the way transactions are held, tills can also operate over 3G which allows tills to be used for shows and exhibitions.

The whole system is infinitely expandable and implements a concept of store/location/tills which means a store can have an unlimited number of locations and tills with minimal additional cost.