What is BACnet/IP?
By Bassirou Thiam, building automation engineer · Updated
BACnet/IP is BACnet carried over standard Ethernet and IP networks. In most BAS designs it forms the backbone that links building controllers, operator workstations and large equipment, while field controllers sit on MS/TP trunks connected through routers. Its default UDP port is 47808.
Where it sits on the riser
The IP backbone runs vertically through the building between switches, with routers down to each MS/TP trunk. Central plant controllers and large air handlers often sit directly on it.
Sources
- BACnet International, about BACnet (ANSI/ASHRAE Standard 135)
- AutomatedBuildings.com, BACnet numbers for MS/TP MAC addresses, device instances and BACnet networks (Contemporary Controls, 2025)
- Siemens, guide specification Section 23 09 00 – Building Automation System (submittals, network, point naming)
Related
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GuidesBACnet device instance numbering and MS/TP addressingThe rules for BACnet device instances, MS/TP MAC addresses, Max Master and network numbers, with segment limits and a numbering scheme you can reuse.