In 2015 the Department for Transport committed almost £50 million to the introduction of WiFi on services run by Southeastern and a few other train operating companies. All our trains will be fitted by June 2018.
Link https://www.southeasternrailway.co.uk/travel-information/on-board/wifi
Link https://www.southeasternrailway.co.uk/travel-information/on-board/wifi