Design automatically
Cabinets, FATs and every cable for GPON or XGS-PON, centralised, cascaded or point-to-point, placed by solvers and checked against your rules. No AI needed.
Learn more →NEWopenFTTH 0.1 beta is out for Windows →Fibre networks, designed
Fibre networks, designed
on your own computer.
openFTTH turns a street map into a complete fibre-to-the-home design: every cabinet, terminal and cable, checked against your rules and priced. Free and open source.
area-small · generic-gpon · solve524 homes · 36 FATs · 2 FDHs
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How it compares
The same design, done three ways.
Drawn by hand, designed by the openFTTH engine alone, and designed with the AI crew. The openFTTH numbers are measured on Brugse Poort in Gent.
| Task | Drawn by hand | openFTTH engineFree, no AI | openFTTH + crewWith the AI crew |
|---|---|---|---|
| A complete design of Brugse Poort524 homes, map to deliverables | Days of drawing and counting | 65 seconds, measured | A few minutes, from one request |
| How you ask for it | Brief a designer | Pick a rulebook, press Design | Type the request in plain words |
| Every rule checked | By eye, when there is time | 0 violations at hand-off | 0 violations, exceptions explained |
| Optical loss for every home | A worst-case estimate | All 524 homes, worst 21.6 dB | All 524 homes, worst 21.6 dB |
| Bill of quantities and splices | Counted in a spreadsheet | 26 priced lines, 2,734 splices | 26 priced lines, 2,734 splices |
| Same inputs, same design | Depends who draws it | Byte-identical, tested | Byte-identical, tested |
| Questions about the design | Ask a colleague | Read the decision log | Ask the crew |
| Risky steps | Whoever draws it decides | Wait for your click | Wait for your click, with the reason |
| Cost | Engineer time | Free | Free on Ollama, about $0.20 a run on the cloud |
openFTTH figures: Brugse Poort, Gent, 524 homes from OpenStreetMap, generic GPON rulebook, field test of 18 October 2026 on a Windows laptop. The cloud cost is a full crew run through Claude on the Manchester field-test area. The hand column describes the work rather than a measurement.
Features
What the app does.
Design, edit, check and export in one desktop app.
Hand edits
Draw the network yourself or move what the engine placed. Rules are checked after each edit, and pinned edits are kept when the engine runs again.
Learn more →AI crew
Type a request. Four AI agents run the engine’s tools and report back; the engine makes every number, and risky steps wait for your approval.
Learn more →Splice schedule
Every closure and every fibre joined inside it. The schedule is rebuilt whenever the design changes.
Learn more →Plan sheets and a priced BOQ
Printable PDF plan sheets and a DXF drawing, a bill of quantities per build phase, cable schedules and a GeoPackage.
Learn more →Version history
Each edit is saved as a version with its reason. You can compare versions and go back to any of them.
Learn more →How it works
Four steps.
Bring the area
OpenStreetMap, GeoPackage, Shapefile, CSV or DXF, in any projection, with ducts, poles and no-dig zones.
Pick a rulebook
Splitter ratios, reach limits, the optical budget and prices, in readable YAML.
Design
The engine clusters homes, places terminals and cabinets, routes every cable and checks every rule.
Export
GeoPackage for your GIS, BOQ and splice schedules as CSV, versioned work orders and the decision log.
AI engines
AI is optional.
All three use the same engine and rules. Only the crew needs a language model.
No AI
€0Design automatically. The engine designs the area on its own. Offline, deterministic, free.
- Same inputs, same design
- Works without internet
Local AI
€0The crew on Ollama. Talk to the crew through a model on your own computer.
- Nothing leaves your machine
- Any Ollama model
Your account
≈ $0.20The crew on the cloud. Claude CLI, Codex CLI, OpenRouter or any OpenAI-compatible key. You pay your provider directly.
- Per full crew run, measured
- No fee from openFTTH
The cloud figure is a full crew run on the Manchester (Chorlton) field-test area through Claude: 147 seconds, about US$0.20 in model usage.
Privacy and safety
Your network stays on your computer.
- Runs locallyThe app, the crew and the engine run on your machine. No telemetry, no account.
- Same inputs, same designA fixed solver seed; the tests fail if the Gent sample stops coming out byte-identical.
- Risky steps need youNew trenches, routes outside ducts and construction exports are refused without your approval.
- Readable settingsMIT-licensed, with rules, prices and solver settings in plain files you can read.
Questions
Questions
Is it really free?
Yes. openFTTH is open source under the MIT licence, with every feature in the free app. The only possible cost is a cloud AI account, if you choose to use one.
Does the AI decide the design?
No. The crew calls engine tools with ids and rule references. Solvers and rule checkers make every number and record a reason for each decision.
Does it need the internet?
No. The app, the crew harness and the engine run on your computer. Fetching OpenStreetMap is an explicit, named step, and Ollama keeps the crew offline too.
Is it ready for real builds?
openFTTH 0.1 is a beta. The rulebook presets carry typical values, so set your own prices and local rules. Risky steps always need a human click, and a qualified engineer signs the final construction package.
Which systems does it run on?
Windows 10 and 11, 64-bit, as an installer or a portable zip. openFTTH checks GitHub for new versions when it starts and offers the download.
Download openFTTH.
Version 0.1.0 beta for Windows 10 and 11. Open an area from OpenStreetMap and design it in about a minute.