BACnet protocol stack

Important Architecture Note

When working with BACnet in .NET, you must understand the BACnet Stack Layers. Most open-source C# libraries focus on the Application Layer (handling objects like Analog Inputs/Binary Outputs) and use a UDP socket for the Network Layer (BACnet/IP).

Recommendation for Developers

If you are starting a new project today:

1. Download the Yabe Source Code: Even if you don't use the GUI, the underlying Bacnet library included in that solution is the most stable and battle-tested C# implementation available.

2. Target .NET Standard: Ensure the library version you pick supports .NET Standard so you can run your code on both Windows and Linux (via .NET 6/8).

3. Check for "BTL Certification": Open-source stacks are rarely BTL (BACnet Testing Laboratories) certified out of the box. If your project requires formal certification for a commercial building, you may need to perform extensive testing or consider a commercial stack like Chipkin’s CAS BACnet stack which provides a C# wrapper.

For C# and .NET developers, there are a few primary open-source options for implementing the BACnet protocol. While many "industry-standard" stacks are written in C, the .NET ecosystem has several mature wrappers and native implementations.

1. BACnet/IP Library (formerly bacnet.net)

This is arguably the most popular and widely used open-source BACnet stack for the .NET ecosystem. It is a native C# implementation, making it very easy to integrate into modern .NET Core or .NET 5+ projects.

• Repository: GitHub - Frédéric Chaxel / BACnet-stack-dotnet (Note: Different forks exist, but Chaxel's is the most referenced for Yabe).

• Key Features:

  • Supports BACnet/IP, BACnet/Ethernet, and BACnet/MSTP (via serial port).

  • Includes both Client and Server capabilities.

  • Used as the backbone for Yabe (Yet Another BACnet Explorer), the most famous open-source BACnet tool.

• Best For: Most general-purpose .NET applications, desktop tools, and Windows services.

2. Yabe (Yet Another BACnet Explorer)

While Yabe is technically a GUI tool for exploring BACnet devices, it is built entirely on the open-source C# stack mentioned above.

• Why it matters: If you want to see exactly how to implement the code, the Yabe source code serves as the ultimate "Reference Implementation."

• Source: Yabe on SourceForge

3. BACsharp

This is another open-source framework specifically designed for the .NET initiative. It provides a structured application layer and network layer.

• Pros: Royalty-free and specifically object-oriented for C#.

• Cons: It hasn't seen as much recent community activity as the BACnet-stack-dotnet library used by Yabe.

• Source: BACsharp on SourceForge