Start with BACnet — the ASHRAE standard for building automation — then learn the platform layer, Tridium's Niagara Framework, and know the other names in the same conversation: Modbus and LonWorks.
Underneath sits the networking: the building's IP network above, the controller layer below.
This page explains what each name is, what a controls technician does with it, and which credential goes with the platform — and says plainly where our research stops short.
What BACnet is and why it matters
BACnet is a standard, not a product.
It is ASHRAE Standard 135 — "A Data Communication Protocol for Building Automation and Control Networks" — and the edition ASHRAE currently lists is 135-2024.
ASHRAE says BACnet was designed for building automation and control applications: HVAC control, fire and life-safety systems, security, and energy management.
That scope is why the name matters to this trade.
A building automation system is many controllers sharing one network, and the work of a controls tech is making that sharing happen — points read, controllers addressed, equipment reporting to the head end.
Two boundaries keep the definition straight.
BACnet is not the controller and not the software — it is the language they share.
DDC is the control approach; BACnet is one of the languages such controllers speak.
How the controller side of the trade compares with the pneumatic systems it replaced is our DDC vs pneumatic guide.
Modbus and LonWorks
Two other names in this conversation are Modbus and LonWorks.
Both are names you may meet on controls postings and inside existing buildings, on equipment and head ends that speak something other than BACnet.
At the job level, "BACnet vs Modbus" is not a contest to settle — a building carries what its project specified, and a tech works with what is there.
One scope note first: this page's research covers exactly one of the three names at the standard level — BACnet, whose name, edition, and purpose ASHRAE publishes.
About Modbus or LonWorks specifications it makes no claim either way.
The device-level answers — what a controller supports and how it is addressed — come from the same places for all three names: the equipment documentation, the point list, and the project's as-builts.
The skill underneath all three names is the same one: identify the protocol layer before you touch the device.
Find out what the head end speaks, what the field controllers speak, and where the two are translated.
That habit carries from BACnet to Modbus to LonWorks without relearning the trade.
Documents beat folklore
Niagara framework and JACE
Niagara is a different kind of name: not a protocol but a platform.
Tridium's Niagara 4 is a framework that building automation projects are designed, engineered, and programmed on — the description in Tridium's own entry-credential course, which trains field service personnel for exactly that work.
A caution on the JACE half of this heading: our research verified the Niagara side of this platform at the level of its entry credential and stopped there.
It did not confirm what the JACE hardware is or where a JACE sits in a Niagara system, and this page will not guess at it.
You may see the name next to Niagara in postings and project documents; when you do, pin down what the writer means — which controller it names, what that controller connects to, and what the seat covers day to day — before you claim or take the work.
For a tech, Niagara is the programming seat.
A project on the framework runs from shop drawings to a commissioned system: build the platform, wire and name the points, program the sequences, and prove them out at startup — the design, engineer, and program work Tridium's course description names.
Networking basics: IP and MS/TP
Under the protocols and the platform is plain networking, and it comes in two layers.
The first is the building's IP network — which may be the same data network the customer's own operation runs on.
When it is, a controls tech is a guest on it.
Find out which network a head end actually sits on before you connect anything, coordinate with whoever owns that network, and document every device you add.
This is also the layer where a mistake is visible to people outside the trade.
The second is the controller layer: the wiring that connects field controllers to each other.
MS/TP is a term you may see at this layer; our research did not verify its specifics — the physical layer, the behaviour, the failure modes — so this page will not guess at them.
What carries over from the first layer is the habit: know which layer a device sits on before you connect to it, and let the project documents tell you what runs where.
The job-skill version of networking: read the architecture drawing and say which device lives on which layer — field trunk or IP network — before you plug in a laptop.
What the role does with that skill day to day is on our controls technician guide.
Niagara certification
The certification question on this page has one verified answer: Tridium's entry credential course is the Niagara 4 Technical Certification Program (TCP) — a hands-on course for field service personnel to design, engineer, and program projects on the Niagara 4 Framework.
The rest of the certification map — credentials beyond this one, and whether a state's low-voltage licence rules reach controls work — is a credentials and licensing question, not a protocols one.
Treat those rules as their own research before you plan around them, and confirm requirements with the bodies that issue them.
Check the class before you budget