What are the different types of BACnet data link layers?

BACnet is designed to work with a variety of data link layers, moving the data from and into the physical communication channels, used to transmit data between devices. The most common types of data link layers used with BACnet are:

• EIA-485: This is a widely used standard for serial communication in building automation systems. EIA-485 supports long-distance communication over twisted pair wiring and provides reliable, high-speed communication.

• Ethernet: BACnet can be implemented over Ethernet using a variety of physical layer protocols, such as 10BASE-T, 100BASE-TX, and 1000BASE-T. Ethernet provides high-speed communication and is widely used in modern building automation systems.

• ARCNET: ARCNET uses a token-passing protocol and is well-suited for low-speed communication over short distances.

• LonWorks: This is a proprietary data link layer developed by Echelon Corporation. LonWorks supports both twisted pair and powerline communication and is used in some building automation systems.

• ZigBee: This is a wireless data link layer that uses low-power, low-data-rate communication for building automation and control applications.

Each of these data link layers has its own unique characteristics and advantages, and the choice of data link layer depends on the specific requirements of the building automation system.