Overview
SDS2-to-Allplan Connection Sync – Proof of Concept. Allplan and SDS2 formed a joint R&D team to explore seamless steel-connection workflows between their flagship BIM platforms. The question: could Allplan users get SDS2-designed connections back in seconds, with every bolt and plate intact?
Apps By TAP built the proof of concept—a C# Windows service that uses the SDS2 .NET API and named pipes to sync steel connections to Allplan in seconds. Its architecture became the foundation of the official Allplan SDS2 Steel Connections add-on.
The Challenge
- Cross-platform data flow: SDS2 and Allplan store connection geometry in very different schemas.
- Real-time performance: Engineers needed round-trip feedback in seconds, not manual exports.
- Loss-less detail: Bolts, plates and hole patterns had to remain 100% faithful when transferred.
- Secure local comms: Corporate environments forbade open ports, so IPC was the only option.
Our Approach
Windows service gateway
Built in C#, the service listens on a secure named pipe and parses JSON requests from an Allplan plug-in.
Dynamic model builder
Using the SDS2 .NET API, the service spins up a headless model session, inserts the requested members and auto-applies SDS2’s connection templates.
Detail extraction
After connections resolve, the service extracts plates, bolts, weld symbols and metadata, serializing everything back to JSON for Allplan.
Stateless request-response
Each call is atomic with no shared sessions, so multiple designers can hit the gateway concurrently without locking issues.
Technology Stack
- C# Windows Service – the always-available gateway. See our desktop software service.
- SDS2 .NET API – headless connection design. Part of our Tekla & SDS2 plugins work.
- Named-pipe IPC and JSON – fast, secure local communication with Allplan.
Results & Impact
- Round-trip time: under 12 seconds for a typical Allplan model selection.
- Data fidelity: 100% match between SDS2 output and Allplan import in pilot tests.
- Path to product: the PoC’s architecture became the backbone of today’s Allplan SDS2 Steel Connections add-on, now in commercial use.
