Phone extensions

I’m retired, with a background in IT, but just getting in to telephony. I’ve installed the Freepbx distro on an old Dell laptop and am currently awaiting delivery of a second-user SPA3000.
My intention is to install a telephony system at our Community Centre, which currently has a single PSTN line to the Clerk’s office. The Centre was originally school buildings and has a substantial ethernet network. We run Windows Server 2003/Exchange Server for admin. and for adult IT classes.
At this stage I’m not after specific technical advice but just a yes/no/maybe to these fairly general questions…

(1) Will we be able to install IP telephones as extensions on our network and access them by dialling in on the existing PSTN line ?
(2) Will we be able to restrict some extensions to emergency calls only ?
(3) Will we be able to restrict some extensions to having access to an outside line only if permitted by the system manager ?

Thanks very much for any guidance you can give.

  1. Yes, you will be able to dial to each extension using your PSTN line. You will only be able to have one call at a time since you only have one line…

  2. You can restrict extensions to only dialing 911.

  3. You can setup PIN codes on extensions to restrict what can be dialed.

Thank you for your very prompt reply, Alan - much appreciated.
Good to know that it’s ‘yes we can’ to all the questions !!
Thanks again