Preventing Ghost Calls on Grandstream ATAs

Occasionally we receive phone calls in regard to Ghost Calls, with the Grandstream ATA Adapters and any other SIP Based Grandstream Product.

This is typically prevented by making the following changes in the settings:

• Validate Incoming SIP Messages. Set to YES for security reasons. This alone can prevent ghost calls!
• Check SIP UserID for incoming INVITE. Set to YES. Again, helps prevent ghost calls during the night. Only set to NO if you need direct IP calling with friends or family.
• Allow Incoming SIP Messages from SIP Proxy Only. Set to YES if connected to a provider. Only set to NO if you need direct IP calling.

You may need to tweak these settings if you experience a loss of all incoming calls, if this happens work backwards and reverse each setting until it works, for some customers the last setting listed was problematic.