 The vast majority of users have best effort packet scheduling services for all their data transmission needs and therefore when user demand is high, or the over the air conditions (radio signal strength, interference ratio and BER) are poor, the conversation appears delayed, cut, bad quality, etc.This behavior is not a VoIP specific problem, but business specific or access technology specific (certain technical aspects must be met for non-delayed data transmission), therefore the same problems are found in any type of VoIP solution.Phone-to-PC calls on computer can be received from landline or mobile phones.