[asterisk-users] Timing, use analog card, ZT Dummy etc.

[voiplist]

Hello, we are setting up another system that will run either 1.2.4,
the latest version of 1.2 or 1.4. We have not yet decided on the
version.

Anyhow, this is a higher volume system (dual processor) which will
handle 30-50 simultaneous calls with 60 to 100 simultaneous channels
lit up. Most calls are g711 with very little g729 and a little gsm
mixed in.

We have a similar system doing exactly this, quite well.

With our existing system we have a single span Digium T1 card
installed, which we never ended up using. Nice it is in there though
because Asterisk uses it for timing.

The new system will be pure IP with no need for Analog or T1 circuits.

Questions are:

1- Can I really get away with using ZT Dummy on a high volume system
like this and put no card in?

2- If I can, should I even risk it or just put a card in?

3- I obviously don't want to put a $500 T1 card in but I do have a
Digium Analog card with 2 FXO modules. I also have some clone cards.
The question is, should I use the clone cards and will they work
reliably just for timing. OR should I use the Digium card?

4- If I use the Digium card in, do I need to also waste a module or
can I just put the bare card in with no modules since it's just for
timing?

Thanks for any help, I will be moving forward today more than likely
and thought I would get a little advice from the list first.