Based on the premise, "When your dog barks, it may be trying to tell you something", DogGuard, the custom-built computer program has been created by Bio-Sense Technologies. The system uses involves a sensor, placed on a wall or fence within a 15-yard radius of the dog, which can determine a dog's stress based on the sound of its bark. If an emergency is detected by a bark, an alarm sounds in the prison's control room. "It collects the dogs' barks through microphones...and sorts and grades them," explained Noam Tavor, head of the Israel Prisons Service canine unit. "It relays only the barks that are significant in terms of security—barks that reveal stress or aggression in the dog."

The first DogGuard system was developed in 2005, and three more have been installed in Israeli prisons.

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