ISDN PPP and fax...?

Hi,

I consider putting an ISDN card in my Linux RH9 box. I want to use the card
as internet connection backup when the ADSL system is down (PPP), ISDN call
logging and also for fax receiving / transmittal (using Hylafax..?)

Which hardware do I need? I have considered the FRITZ!Card PCI ISDN v2.0
and some Eicon mdels, maybe Diva PCI model 600-750 or Diva PCI 2.01 model
311-142.

Can I use one of the above cards to achieve the described functionality?

In any case, thanks for any hints on [affordable] hardware, drivers and
howtos on this issue

thanks in advance

best regards

Tor