The following is true if public and private numbers are identical:

• A Public Number must be owned by us (ported to us, so calls are answered by an IVR application).
• A Private Number matches the public number (same number) agent signs in with the public number.
• Requires a SIP-trunk to the PBX responsible for terminating the call to the agent.
• PBX must be able to route incoming calls received on the public number internally (without sending the call to the PSTN).
• The PBX requirements are important to avoid looking (some level of protection is in place to avoid certain loops, but in the event of looping the calling user will not be able to connect.
• More ports are used with hosted DIDs: 4 ports as opposed to 2 ports.
• Used by people that take direct calls, so the CCA knows to accept the calls.