Because RingCentral is cloud-based, it’s not dependent on your power or internet connection to continue receiving calls or faxes. Use your mobile phone as one of your forwarding numbers so even if your office internet or power is lost, your calls can still be made and received from your cell phone and even show your business number (RingOut, RingCentral Office iPhone app). Even your faxes can be accessed from your email or browser on your cell phone.