About the functionality of security devices

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

Now it is fashionable to talk about security systems that are somehow connected to the smart home, which are controlled by the application from a smartphone or from a personal account online, but there are also customers who just need their property to be safe so that in case of an alarm the rapid response team arrives and solved all the problems. Maximum security and minimum problems. This is especially true of business customers. Business is more demanding of the security system functionality 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 may belong to different owners.

The projected 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 describe a kind of generalized security system, the functionality of which in one form or another is implemented by most manufacturers.
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A zone is something like a logical sensor that combines one or more physical sensors . For example, the “Window” zone may consist of two wireless sensors: an opening and a broken window. Thus, all physical sensors (wireless and wired) connected to the security system are distributed over zones (wired, if desired, can be combined manually during installation). Zones can be guard, fire, technical, round the clock, etc. Algorithms of reaction to various events will depend on this type of zone.

A section is a logical unit of a protected object, for example, an office, a room, a warehouse, a house, a perimeter. Section combines one or more zones. In this case, different sections can use the same zones. This is the section we set up or disarm.

The object represents all the property of the client. The device may contain several sections operating independently of each other. Sections of different objects may intersect (In diagram 3, the section of the first object is at the same time 1 section of the second object). For example, there are offices of two different campaigns in the building, 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 specific logic of operation when removing and arming. (It will depend on other partitions, usually this dependent partition is armed last, and removed - first). The object is protected if at least one of its sections is protected.

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

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


Here, too, is not so simple. Different indicators, electric locks, sirens and anything else, up to a fire extinguishing system, are usually connected to a security device and expanders. Emerging events react differently. Something flashes at different intervals, something turns on once, something turns on for a short time and turns off. Events are many: arm / disarm, alarms, errors, delays, fire and many others. It is required that any output could subscribe to several events at once, and for each event it was possible to establish an algorithm for the output work (frequency, 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 worthy device can not do without a wireless system , which means that we need support for wireless sensors from different manufacturers, even the most popular ones. This may be, for example, a wireless expander unit that is connected via RS485. Here the next snag is that the wireless from different manufacturers means absolutely everything: protocols, hardware, ways to register, control, update, work with wireless expanders and repeaters. The full integration of even one such system (in its full functionality) is a rather difficult task. And even one manufacturer of wireless systems may have several versions of the protocol, devices that mutually exclude each other. Therefore, sometimes a part of the possibilities embedded in the system has to be consciously abandoned. When wired sensors are connected, it is required to register their triggering, breakage and short circuit on the line, as well as calibration. Wired sensors have only one drawback, compared to wireless ones - these are, in fact, the wires themselves, the need for their installation. 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 unguarded in any way, which means that background loading should not interfere with the main work and should always be possible 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 with an emphasis on functionality, because it is understood that the configuration, maintenance and support will be carried out by technical staff security company. In more simple 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 configuration and control settings. Modern security systems may soon become heaped “Combines”, which can be very flexibly configured. Already, in addition to security and fire algorithms, they integrate the functions of access control systems, video / photo confirmations of alarm triggering, voice acting events. Somewhere you can directly from the device to call the operator on the remote. You can manage the system online. Each exit of the technician bears additional expenses, so that more and more security companies try to limit themselves to remote control and go to the site only as a last resort.

Added the ability to link the security system with third-party services and applications. There are also mobile applications that allow you to optimize the work of the RR and reduce the response time to anxiety. It remains to hope that all innovations and innovations will not be at the expense of reliability and safety.