What is building automation (GA; Building Automation)?

Building automation is revolutionizing the way buildings are operated, controlled and monitored. It is an advanced system that uses modern technology to optimize the efficiency, comfort and safety of buildings. It integrates various systems such as HVAC (heating, ventilation, air conditioning), lighting, security technology and more into a central platform for efficient control and monitoring. The main advantages of GA are improved energy efficiency, lower operating costs, increased comfort for residents and simplified maintenance. A GA usually consists of three logical levels: the field level (sensors and actuators), the automation level (controllers) and the management level (monitoring software).

Why do we need protocols in building automation?

Protocols are essential in building automation because they enable seamless communication between different devices and systems within the building. Building automation often uses products from different manufacturers that may use proprietary communication methods. Protocols serve as a common language that ensures interoperability and avoids data silos. Extensive data exchange in real time in particular enables rapid reactions to changing conditions and can therefore Improve overall system efficiency.

Which protocols are used in which combination?

These protocols are often only one component in a more complex toolchain. In order to make the complexity of a toolchain visible, we conducted a survey in the spring of 2024 to capture the typical application combinations for protocols. These protocols are often used in combination with the following components: Software for monitoring and analysis, databases for storing measurement data, measurement concepts for structuring measurement data, data point schemas for structuring (meta-)data, and programming languages for analyzing and linking the building blocks.

Various protocols that were recorded in summer 2023 and spring 2024 are described in detail on the page. These were compiled through research in the relevant specialist literature, in documentation of hardware and software, energy transition building research projects, and surveys. We have selected 12 commonly used and modern protocols and summarized the following characteristics for them:

• Name of the protocol
• Transmission media – How is data transmitted between the various components and devices within the system (wired, wireless or wired & wireless)?
• Supported transmission media – how are signals transmitted?
• Related standards – specific standards to which each protocol can be assigned.
• Open-Source-status – is the protocol public and freely available?
• License fee – Is there a fee to cover the costs of use and/or certification?
• Network topology – what is the physical and logical arrangement of devices and components in a network?
• Implemented security mechanisms – whether and what mechanisms are implemented in the protocol to ensure data security?
• Bandwidth – the capacity of the communication channel to transmit data between the various components of the system.
• Frequency – the frequency, wavelength, or carrier frequency used by the wireless communication devices in the system.
• Range – the maximum distance over which communication can be maintained between the various devices and components of the system without the signal strength becoming too weak.
• Implemented OSI-layer – the application of the layers of the OSI reference model for communication between the various components of the system.
• Levels of building automation – the hierarchical structure of a building automation system.
• Data model architecture – how do you add information or attributes to an object?
• Discovery – whether the protocol has the “discovery” function to automatically identify devices during data transfer?
• Multi Master – Can several master devices act at the same time?
• Priority – Procedure for how the changes or updates are made.
• Typical application – If applicable, exemplary application.