About the functionality of security devices

When developing modern security systems, developers sometimes have the task, on the one hand, to make a device that is flexibly customizable for any type of object, and, on the other hand, to make its configuration and operation intuitive. In this article I tried to describe and summarize the functionality that is usually implemented in security remote control devices.

Now it’s fashionable to talk about security systems that are somehow connected with the smart home, which are controlled by the application from a smartphone or from your personal account online, but there are also customers who just need their property to be safe, so that in case of an alarm a quick response group arrives and solved all the problems. Maximum security and minimum troubles. This is especially true for business customers. Business is more demanding on the functionality of the security system and its reliability. Complex commercial objects can be quite large and cleverly configured: with different access levels, with different alarm response algorithms, with many expansion units and a myriad of sensors, combined with a fire alarm, different rooms can belong to different owners.

The designed configuration of a security system of this kind usually consists of some blocks. The relationship of such blocks is simplified in the diagram.


Let me explain that here we are describing a certain generalized security system, the functionality of which in one form or another is implemented by most manufacturers.

A zone is a kind of logical sensor that combines one or more physical sensors . For example, the “Window” zone may consist of two wireless sensors: for opening and for breaking a window. Thus, all physical sensors (wireless and wired) connected to the security system are distributed into zones (wired, if desired, can be combined manually during installation). Zones can be security, fire, technical, round-the-clock, etc. Algorithms for responding to various events will depend on this type of zone.

Section- This is a logical unit of the protected object, for example, an office, room, warehouse, house, perimeter. A section combines one or several zones. However, different sections can use the same zones. It is the section that we put or disarm.

An objectrepresents all of the customer’s protected property. The device may contain several sections that operate independently of each other. Sections of different objects can intersect (In Figure 3, the section of the first object is simultaneously 1 section of the second object). For example, in the building there are offices of two different campaigns, and there is one common entrance and corridor, in which case these rooms are allocated in a separate general section, which will already have its own special logic of work when disarming and arming. (It will depend on other partitions, usually this dependent partition is armed last, and removed first). An object is under protection if at least one of its sections is under protection.

Usercan manage (locally or remotely) only those partitions that are available for its access level. The same applies to control panels at the facility, their scope is limited to certain sections.

Now for the outputs , i.e. executive devices (relays, keys) in the security system.


Here, too, is not so simple. Different indicators, electric locks, sirens, and generally anything, up to the fire extinguishing system, are usually connected to a security device and expanders. The outputs react to different events in different ways. Something blinks at different intervals, something turns on once, something turns on briefly and turns off. There are many events: arming / disarming, alarms, errors, delays, fire and many others. It is required that any output can subscribe to several events at once and for each event it is possible to establish the algorithm of the output (periodicity, duration, etc.). Each event has its own priority, so that when several events occur simultaneously, the outputs execute their algorithms according to this priority.

A decent device can not do without a wireless system, which means that you need support for wireless sensors from different manufacturers, at least the most popular. It can be, for example, a wireless expander unit that is connected via RS485. Here's another catch: wireless from different manufacturers is absolutely different: protocols, hardware, methods of registration, control, updates, work with wireless expanders and repeaters. The full integration of even one such system (in its full functionality) is a rather difficult task. And also, even one manufacturer of wireless systems may have several versions of the protocol, devices that are mutually exclusive. Therefore, sometimes part of the capabilities inherent in the system has to be consciously abandoned. When connecting wired sensors, it is required to register their operation, open circuit and short circuit on the line, and also do calibration. Wired sensors have only one drawback, compared to wireless ones - this is, in fact, the wires themselves, the need for their laying. But they are cheap and reliable, do not require maintenance (no need to change batteries).

When performing a remote update of the firmware of the device or its modules, you need to be very careful in this process, not forgetting that the object should not remain unprotected in any case, which means that loading by the background should not interfere with the main work and there should always be an opportunity rollback if something went wrong.

Such an abundance of configuration settings is quite problematic to fit into a concise interface that will be understandable at a glance, and alas it happens that manufacturers do not focus much on design and usability by focusing on functionality, because it is understood that technical personnel will configure, maintain and support security company. In simpler devices, designed for ordinary users and for simple, small objects, there is already a beautiful design of web and mobile applications, and obvious and concise settings for configuration and management. Modern security systems may soon become sophisticated “Harvesters”, which can be configured very flexibly. Already now, in addition to security and fire algorithms, they integrate the functions of access control systems, video / photo confirmation of an alarm, voice acting events. Somewhere, you can directly call the operator to the console directly from the device. You can manage the system online. Each exit of the equipment carries additional costs, so that more and more security companies try to limit themselves to remote control and go to the facility only as a last resort.

Possibilities are added to link the security system with third-party services and applications. There are also mobile applications to optimize the operation of the GDB and reduce the response time to alarms. It is hoped that all the innovations and innovations will not be at the expense of reliability and safety.