The Expo server is (2017) an Acer Aspire netbook. Plugged into it with cables are
The Expo laptop 'tunnock' is another laptop which is connected to the server by a cable and not by WiFi. It runs Linux and has installed all the software for talking to the server for:
Any laptop or phone can connect to the server via the "tattyhut" WiFi and, with some configuration, can be set up to do all those things too (but nothing else - it is not connected to the internet). New expoers are advised to use the Expo laptop first to see how it all works.
Either the Expo laptop or your own laptop will use the version control system to synchronise cave data. Many people prefer to use the expo laptop 'tunnock' as then they don't have to install any software on their own machine.
[Through the miracle of the distributed version control system, people who take their laptops home (or across the road) to connect to the internet can update the public server expo.survex.com with all the latest cave surveys. Rely on other people to do this is this is your first expo.]
At the end of expo the server is brought back to the UK and any remaining updates are synchronised with the public server expo.survex.com .
For some years the Expo server has served it's own DNS domain name "potato.hut" and published WiFi as SSID "tattyhut" as it's own private network - which was NOT connected to the Internet.
In 2017 the hard-drive died and as part of a general reconfiguration we are intending in 2018 to connect the server to the internet via the Staudnwirt router (which provides the WiFi over the road). This may not work...