The building model

Most design tools store a drawing. This one stores a building, and the difference shows up in what happens when something changes.

What the model holds

Four things, entered once:

• Geometry — walls, doors, windows, ceilings, floors, and the zones that give a space a name and a requirement.
• Materials — what each surface is made of. This is not cosmetic: it is the input to radio-frequency attenuation.
• Structure — racking, cabinets and equipment that occupy space and block things.
• Devices — cameras, access points, readers, locks, speakers and the rest, each carrying its own datasheet rather than being a generic symbol.

The last point is the load-bearing one. A camera on the plan is not an icon; it holds a lens, a sensor, a resolution and an infrared range. An access point holds a radio, a transmit power and an antenna pattern. That is what makes the coverage a calculation rather than a drawing.

Why one model rather than one per discipline

The alternative — a drawing per trade — has a specific failure mode. The Wi-Fi plan and the camera plan each hold their own idea of where the walls are, and when a wall moves, one of them gets updated. The design is now internally inconsistent and nothing will tell you.

Here the wall exists once. The radio-frequency engine reads its material to compute attenuation; the optical engine reads its geometry and height to decide line of sight. Move it, and both are reading the new position because there is no second copy to forget.

Network topology behaves the same way: it is derived from the devices actually placed rather than drawn by hand, so the same design always produces the same topology. You cannot get into the state where the topology diagram and the device schedule disagree, because one is a function of the other.

The order the work happens in

1. Bring in the plan. Upload the floor plan and set its scale against a known dimension. Everything downstream inherits that scale, so it is worth getting right.
2. Confirm the shell. Walls, doors and windows are detected and proposed; you confirm or correct them. Materials are set here, and this is the step that determines how good the physics will be.
3. Define zones and requirements. A zone is where a requirement lives — this area needs Identify-grade camera detail, that one needs a particular coverage level. Requirements set here are what the design is later scored against.
4. Place devices from the library. Real products with real specifications, so the calculation has something to work from.
5. Compute and read. Coverage, cable runs, power budgets and topology. Walk it in 3D and read the numbers where you would be standing.
6. Produce the deliverables. Plan sets, schedules, submittals, the bill of materials and the scope of work — generated from the model rather than assembled separately.
7. Install and close out. Field tools carry the design to the technician; verification and photos come back; the as-built is derived from the same record rather than redrawn.

What to read next

The calculation articles give the formula behind each computed number, along with where each one stops being valid. Start with whichever discipline is carrying the risk on your job — that is usually the one a customer will question first.