We are trying to set up a customer that has an Avaya Partner ACS system. They would like their 18D phone in the warehouse to be used like a 2way talkback speaker. For example, ext 11 would like to call the warehouse speaker, "Bob, are you back there?" & then Bob could reply saying, "yes, what do you need?" and the conversation could go on without having to go over & press anything on the phone.

Is this possible? What additional equipment is needed?

-Thanks