Who is Zens Phone Wholesale Partner?? - (ISDN?)

I have a friend who's setting up a business doing voice over work so he needs an dual channel ISDN line.

I know they are rare, but we've heard good things about Zen Internet.

Who is Zen's wholesale phone partner for phone and ISDN, and is the wholesaler different between Consumer and Small Business.

Any advice or help appreciated. He's an absolute stickler for detail so the more information the better.

Do they still sell ISDN ports?

I know dialup is as hard to find as a unicorn unless it's a pay per minute ISP.

If your friend is a "stickler for detail" why on earth isn't he asking Zen ?

In reply to a post by AdrianPH:

If your friend is a "stickler for detail" why on earth isn't he asking Zen ?

Agreed. Also why Dial ISDN? I could never see the benefits of Home Highway when I had it - to when ADSL came along.

ISDN for voice I still a valid choice - gives options for DDI for example...

Yes - I was wondering if they still do data with it also?

64k/128k ruled in it's time - but in 2016?

I still use a lot of basic rate ISDN (Openreach), a lot of broadcast still uses it as well for the guaranteed audio quality.

What did used to rule was data over the 'D' channel which was very useful for being always on at no cost.

I remember home highway and 128k connections with firefly - but that's about it.