Portable electronic device having an external I/O unit and power
Portable telephone
Post-delivery support system for private branch exchanges
Pre-biller capability in enhanced charging collection...
Pre-paid calling and voice messaging services for inmates
Pre-paid card system and method
Pre-paid card system and method
Pre-paid telephone calling card linked to a stored value...
Pre-paid wireless interactive voice response system with...
Pre-paid wireless interactive voice response system with...
Pre-paid wireless interactive voice response system with...
Predictive bursty real-time traffic control for...
Prepaid billing support for simultaneous communication...
Prepaid calling time processing: a method and apparatus for...
Prepaid calling time processing: a method and apparatus for...
Prepaid calling time processing: a method and apparatus for...
Prepaid calling with warning announcement
Prepaid long distance call system and method
Prepaid long-distance telephone service system with flexible ope
Prepaid long-distance telephone service system with flexible ope