Another set of application areas is in the medical and communications industries. For medical, it can be used in microwave therapy, patient monitoring, and electrocardiographs, as well as defibrillators. The primary task in medical is isolation between the power and delicate system components. From a communications perspective, it can be seen that there are a multitude of different applications: modems, ISDN, Ethernet, switching equipment. The primary task for communications is isolation between the power and the rest of the system, as well as isolation of the bus nodes to prevent corruption of the complete bus.