An alarm system that uses a sound- or light-generating device located on the exterior wall to alert on a violation is known as a(n):

A local alarm refers to a system designed to alert individuals in the immediate vicinity of a violation through sound or light, often through devices mounted on exterior walls. This type of alarm serves to draw attention and deter intruders by creating noise or visual alerts, thereby enabling anyone nearby to take action or contact authorities.

Local alarms are frequently used in residential and commercial properties to provide a quick response to unauthorized access, as they do not typically send signals to a monitoring service but instead rely on the reaction of nearby individuals. This aspect of functioning is pivotal in providing a deterrent effect, emphasizing the alarm's purpose to immediately notify and alert rather than waiting for external intervention.

In contrast, other types of alarms like intruder alarms may integrate a broader range of features and monitoring capabilities, while proprietary or direct alarms refer to systems that function differently, often involving professional monitoring or direct connections to security personnel. Thus, the conceptual focus on immediate vicinity alerts and the physical response capability of local alarms underscores why this answer is accurate.