[Asterisk-Users] ISDN phones & Asterisk, ASDI and then some

[Patrick]

Hello all,

New to the list, Asterisk and this wonderful world of convergence. From
reading the docs, list and websites I hopefully correctly understand
that I can use a plain cheap isdn4linux supported ISDN (passive) TA to
hook up the PC to the ISDN line from the telco (FXO card?). Next in the
PC I also need a FXS card like a Digium TDM10B or PhoneJack so I can
hook up an analog phone to it.

In sort of graphics:

analog phone === FXS card - PC - FXO card === Telco/PSTN
                 PhoneJack       ISDN TA      ISDN
                 Digium TDM10B

Questions:
1) Is my description above right?

2) Is there a FXS card to which I can connect an ISDN phone?
   I have read some messages saying it can not be done with current *
   I read that a Teles ISDN TA can be configured as a TE (terminal
   endpoint) *or* NT (network termination). It's the ability to be
   configured as a NT which seems to be the solution. If the FXS TA were
   configured as an NT wouldn't the ISDN phone think it was hooked up to
   the PSTN. Now only * needs to do some magic :) Makes sense?

3) is it possible that an existing pbx infrastructure is upgraded to an
   * solution where the existing phones can talk to * just fine?
   In other words: is there a general compatibility between phones from
   various brands and PBX's from other brands? It would financially be
   less attractive if a customer would have to buy a whole new set of
   phones...

4) what is an ADSI phone? I read on the list that they are cheap ($50)
   so I may want to invest in a couple in case * can't talk to my ISDN
   phones. Any vendors websites were I can read about these ADSI phones?

5) Integrating xDSL in an * box seems like an idea re VoIP. Anyone
   have some suggestions what brand PCI ADSL cards work with Linux and
   play nice with the Telco's DSLAM equipment (preferably in .nl)?

6) any DECT (for digital wireless phones) PCI cards and DECT Cells out
   there with Linux support? Would be cool to be able to offer service
   to wireless digital phones also

7) Finally, are there any business cases with some nice financial
   numbers that compare e.g. a basic 4/16 * based building block to
   commercial offerings in terms of pricing, functionality, scalability
   etc.?

Thanks for your time and advice!

Cheers,
Patrick