The idea that the border issue is intractable in the current EU/UK talks over Brexit has gained a lot of press attention of late.
A paper written by Dr Graham Gudgin and Ray Bassett claims that the UK government should pursue the maximum facilitation arrangement a.k.a. ‘max-fac’, whereby new technologies would be used to create the “frictionless” border. One problem there is that even the UK government's own people suggest that the technology does not yet exist and is at least 4 or 5 years away in development ( and that assumes it can be done).
One has to believe that when push comes to shove, there will be no hard border on the island, as such a step would be retrograde in every way.
Politics is after all the art of the possible - finding a way, be it a fudge or a compromise or a rabbit out of a hat, is what it's all about.