I have 3 Government depts all using an Option PBX. They will be moving to a new building but are no longer to share phone system. They will have ONE receptionist in the lobby area for all three depts. What suggestions do you have for being able to have the operator pick up ONE phone and still be able to call the 3 different depts?? i.e. what would be the best way to tie them together to get an intercom call back and forth? As yet, I don't know if the receptionist will be the only one needing to do this, or all people will need to call back and forth.
I need suggestions for either just one person or many people.

My first thought if just the one person will be using an ATA to a line card. Any other thoughts?

Thanks

mck if you wanna share or SRG/bcm for the surviorbility.Opx"dry pair" with ATA's work but there is no supervision or Breakout some channels for dialtone from routers and with ATA's on one side and trunk cards on other u can dial ext other side can use AA on vm to dial

Depends on budget...

ATA'a, E&M or PtoP PRI.

That was my first thought.
Would a PRI to PRI work with dry pair between??
Then can you send and receive digits for target lines ??
I don't need anything else between the PRI's except wire? or course T to R and R to T.

I don't know... you may want to check with your telco if the can provide dry pairs... I have my doubts.

with PtoP you can set up a dialing plan and use internal receive digits.

I should not need Telco for the dry pairs. These systems will all be in the same building. I can just run cable myself. I just want to make sure that in theory, and in reality, this should work with dry cable between PRI's and it should send digits and be able to use target lines.