Statistical methods are used to observe packet flow arrival processes and to infer routing changes from those observations. The waveguides define an inlet face at one end and a screen at an opposite end, with each waveguide having a core laminated between cladding. The PPRC acts as a single PDSN, as well as a surrogate PCF from the perspective of the PDSNs in the private IP network of the service provider. The simulation tool predicts the response of the object to ultrasound from the ultrasonic transducer. The second tunneling rate is coupled with the third function to obtain a third tunneling rate. The currents flowing through the first and second transistor are forced to be equal.