In a software-defined network, the data plane handles packets under the direction of a control plane, but the controllers are just applications that can run on standard x86 hardware. SDN controllers use a standard protocol (OpenFlow) to communicate with data plane devices. Other specialized network appliances -- like firewalls and load balancers -- that get recast as SDN applications also run on standard x86 hardware using the SDN controller to get the data plane devices to do what they need to do.
A testator must be of sound mind when making a will. In part to ensure that a testator is of sound mind, states require that the signing of a will be witnessed by multiple persons. A testator also should be making the will without duress and free of coercion from other persons.
A defibrillator is a device that introduces electrical current or shock to the heart to correct cases of ventricular fibrillation (a quivering of the heart which limits the heart muscle from pumping blood to the body), cardiac arrhythmias (abnormal electrical activity), and ventricular tachycardia (fast heart rhythm).