What are the requirements for allowing agents to work off-hook. The documentation says,
Oracle Contact On Demand users can choose to set their MSI extensions to work off-hook. With the off-hook option, there is no ringing, and a beep is played when a call is delivered to the agent. When users are working off-hook, they can also have calls auto-accepted without having to manually answer each call.
Does this mean that the on premise phone system needs special hardware?
No special equipment is required. Simply enable the checkbox and after your 1st phone call don't hang up the phone. Subsquent calls will not require the system to dial your line again. If you are set to accept the call automatically, you will hear a beep (or a whisper prompt if created and provisioned). Otherewise, the agent must click accept.