A great machine which allows you to take cards in lots of parts in your building is called a Bluetooth Portable and this uses a signal to transmit between base unit which then calls with internet or phone connection.
A lot of people who have this are Bars or restaurants that use this sort of machine because they must let people use cards whilst eating at tables, although, this can be for other instances also.
This type is mostly for persons that must accept card on the move and is known as a mobile, it only needs a connection with a sim for you to work it. It is one that can be taken out and around so you could allow card throughout the United Kingdom and you'll not need the usual line.
The latter one is the static one which is for people that need to receive cards in a specific place near to power plug and a Ethernet or phone.