If the municipal code requires a fence, and does not address electronic systems, then the dog owner must provide a physical fence, not an electronic one.
Some codes specifically forbid electronic pet containment systems ("Dogs shall not be considered confined to the premises of the residential property of their owner, keeper or harborer if the only restraining device is an electric fence.") These codes use the term "electronic fence" without stating exactly what devices are forbidden (review the different products that are described above, and try to determine which is an "electric fence" and which, if any, are not). Due process requires that a prohibition must be stated clearly, or else is unenforceable. If an individual is not sure whether a particular system violates a local ordinance, he can speak with a supervisor at the animal control department and ask for guidance.
But many cities have made it legal to use electronic fences and electronic collars. An example is the Overland Park Municipal Code 6.08.020. The second subsection 3 of subsection (a) provides:
Dogs may be confined to the premises of the residential property of their owner, keeper or harborer by an electronic fence or an electronic collar. An electronic fence or electronic collar is defined as a fence or a collar that controls the movement of a dog by emitting an electrical shock when the animal wearing the collar nears the boundary of the owner's, keeper's or harborer's property. The collar may be controlled manually by a person or automatically in a predetermined manner. Dogs confined to residential property of the owner, keeper, or harborer, by an electronic fence or an electronic collar, shall not be permitted to be nearer than 10 feet away from any public sidewalk or property line that is contiguous to neighboring property. In addition, dogs are prohibited from being confined by an electronic fence or an electronic collar in the front yards of an owner's, keeper's or harborer's property. No dog having been found a dangerous animal by the animal control division shall be confined by an electronic fence or an electronic collar. All owners, keepers or harborers of dogs who use an electronic fence shall clearly post their property to indicate to the public that a dog is confined to the property by an electronic fence or electronic collar. Electronic collars may not be used to control a dog when it is off its owner's, keeper's or harborer's property.
The problem mentioned above applies here too: if an electronic pet containment system is not an "electronic fence" or "electronic collar," apparently the dog owner will not benefit from the loosely worded ordinance.