BACnet supports a total of 9 different network media (data-link-layer).

Those are:

  • BACnet Ethernet (ISO 8802-3 aka Layer-2 Ethernet, rarely used)
  • ARCnet (Network or EIA-485, rarely used)
  • LonTalk (any media supported by LonTalk, rarely used)
  • MS/TP (Master/Slave Token Passing) based on EIA-485 (serial networks, commonly used)
  • PTP (Point-to-Point) based on EIA-232 (serial connection, rarely used)
  • BACnet/IP (based upon IPv4 and UDP communication, commonly used)
  • BACnet/IPv6 (based upon IPv6 and UDP communication, rarely used)
  • ZIGBEE (wireless mesh networks, rarely used)
  • BACnet/SecureConnect (based upon TCP / websocket based communication, rarely used but expected to be commonly used in the future)