These systems are mounted on or fastened to the fencing and follow the periphery of the protected object. This ensures the fastest possible detection and thus also the most response time. These systems take up very little space. They are easy to mount, although the fencing should meet a few requirements to ensure that the systems function properly. There are various detection techniques, each with their own specific features. The fencing should be high enough to act as a barrier, as all detection methods operate by registering the fence being manipulated in some way. The best method depends on the project. Some of the systems for fencing can also be used to protect walls and roofs.