Thanks again
buttsie 
Interested to learn from the VPN link you provided.
I've always left the technicalities to one side
but there's only so long a person should suspend that ignorance
slightly connected note, as an admirer of the mathematician (& polymath)
Cliff Stoll from his TED talks & videos on
Numberphile.
I only recently learnt he was one of the first ever people to track a hacker so I ordered the book just yesterday
https://en.wikipedia.org/wiki/The_Cuckoo%27s_Egg