Public sector
Shared AV equipment in a common meeting room
The EDID table in the display is overwritten by the fourth computer connected, so the fifth gets a black screen — which is exactly the inconvenience that breeds the workaround.
- Area
- KVM & VTC
- Architecture patterns
- 1
- Products used
- 5
The problem
What makes it hard
The cheapest and most common case, and the one the HDMI diode is explicitly built for: “ideal for high-security environments such as meeting rooms with shared AV equipment”. One screen, one cable on the table, and a succession of computers at different levels connected to it over a week.
The shared cable nest on the table. Somebody plugs in a USB-C dock carrying both video and data. A wireless presentation dongle is bought by an administrator who did not know. And the EDID table in the screen is overwritten by the fourth computer connected, so the fifth gets a black screen — which is exactly the inconvenience that breeds the workaround.
How it is built
The display as a pure receiver
HDMI is not one-way: DDC runs in both directions, and EDID is a shared, writable object.
See the full pattern- One-way path
- Data path
- Path that does not exist
In the catalogue
Equipment from the catalogue
Built from: HDMI Diode 60-00-9155, Monitor 55" Level B 50-70-3148, Monitor 55" Level A 60-00-7728 and 2 more below.
TEMPEST Level B · RÖS U2
Monitor 55" Level B
- Screen size
- 55”
- Optimal (recommended) resolution
- 3840 x 2160 @ 60 Hz
- Display area
- 1210 x 680 (WxH) mm
Product no 50-70-3148
TEMPEST Level A · RÖS U1
Monitor 55" Level A
- Screen size
- 55”
- Optimal (recommended) resolution
- 3840 x 2160 @ 60 Hz
- Display area
- 1210 x 680 (WxH) mm
Product no 60-00-7728
Standard
HDMI–HDMI Fiber Optic Converter
- Connector
- IEC 60320 C14
- Dimensions
- 32x130x217 (HxWxD) mm
Product no 60-00-7909
Standard
Secure USB Disconnect Conference
- Dimensions
- 38 x 100 x 100 (HxWxD) mm
- Weight
- 300 Gram
Product no 60-00-0235
Reading and references
Explained in
Named customer references are not published. What we can show is the solution area this environment belongs to, and the reasoning behind the design.
Environments
Environments with the same problem
The technology is the same; the buying process usually is not.
- Briefing roomA shared room is harder than a single workstation, and the bridge for an external client is a deliberate compromise that must be decided in advance.
- Boardroom in a protected companyThe people in the room have decision authority and no security training, and the equipment has to work without either.
- Training facilityStudents bring their own devices, and a room designed for teaching is designed to be connected to.
- Negotiation room in the private sectorThe threat is commercial rather than state-level, but the room is used by people who have never been briefed.
Next step
Describe your environment
If yours is close to this one but not the same, that difference is usually where the design decisions are. Tell us what it looks like.
Verified credentials
All certifications- NATOCertified TEMPEST supplierSDIP-27 · Level A & B
- Government of SwedenSupplier to Swedish authoritiesPolice · FMV · FOI
- Swedish Armed ForcesM-numbered equipmentMain supplier, Total Defence
- ISO 9001 14001ISO certifiedQuality & environmentDownload certificate (JPG)
- SOFFDefence industry memberExport control frameworks
- Made in SwedenDesigned & built in StockholmSecure supply chain
