To prevent unauthorized use of corporate telephone systems, MBG provides secure authentication for both MiNet and SIP devices. Clients must pass a registration at the MBG server before being passed through to the ICP for approval.
MiNet device access is restricted to authorized users by default. Although we don't recommend it, you can lift the restriction and allow users to pass through directly to the ICP.
SIP device access is always restricted to authorized users. This setting cannot be changed.
For more information, see About MiNET and SIP Restrictions.