Not an NGN I know but I think others should be warned about this no.   Today I received a call for my husband while he was out from a woman who said her name was Sinead and she was "calling from Barclaycard".   After agreeing a time to call back (she hasn't!), I became suspicious & did 1471 which showed this number.  As it was obviously not a Barclaycard no, I googled it which brought up a warning that it is operated by LBM Direct Marketing, sometimes known as or part of ICT Group and is notorious for silent calls etc.   It has been reported to OFCOM etc without any success (not surprising!) and it ignores whether a number is on TPS.   I rang Barclaycard, had to go through to their Fraud Section because all the other numbers kept me on hold, cutting off after 8 mins - I had used 141 + the geo nos.  They confirmed they had not called me but knew of this company which they use for marketing.  I pointed out we were on TPS, did not want any marketing and the caller was purporting to be a Barclaycard employee & the person said she will pass it on to her team leader.  However, I thought users of this site should be warned.   It is also yet another example of how useless the regulators are in protecting consumers.   This company is practising deceit and lying to those they call by impersonating employess of another company and yet nothing is done.

It was the woman at Barclaycard Fraud Section who told me that ICT & LBM were connected, have checked the ICT site you mentioned & it seems they outsource so may be they use LBM for certain things.