Does Vapi AI offer full integration RingCentral phone system my business uses right now?

Hi JohnnyM, Vapi AI doesn't support SIP registration with RingCentral directly. You can use an intermediary SIP provider like Twilio or Plivo to set up a SIP trunk and connect the two services. For more details, check out [Plivo SIP Integration](https://docs.vapi.ai/advanced/sip/plivo). Let me know if you have any questions.