Intelligent Controllers
DESI Controller
Replaces the end-of-line resistor and gives every analog sensor a cryptographic identity.
The Digital Encrypted Security Interface is a miniaturized computational element inches from the sensor or control device. It replaces end-of-line resistor loops and unprotected relay controls with a FIPS-compliant cryptographic identity, so data is authenticated at the far edge.
- Category
- Intelligent Controllers
- Certifications
- UL 294 · UL 2610
- Configurations
- 3 variants
Trust where none existed
DESI installs in the sensor or at the output device, replacing vulnerable end-of-line resistors with challenge-response authentication of every input before acceptance and every output before command execution. Tamper, side-band attacks and loss of control voltage are reported as alerts.
Over the wiring already installed
Multiple DESI devices run over a single pair of wires, so a door’s request to exit, lock control, door position and tampers travel one pair to the panel, cutting cabling by over half. Existing sensors, locks, readers and building controls keep working, with no special wiring or retrofit.
Genuine from the factory
Each DESI carries a globally unique identifier and a write-once OEM data page, so sensors and electro-mechanical devices can be verified as genuine products of their manufacturer. Private keys are generated on the device and never exposed, with four root rekey events over its life.
- Replaces end-of-line resistors with authenticated inputs and outputs
- FIPS-compliant PKI; private keys generated and held on the device
- Up to 64 DESI per gateway or EM-16 over existing wiring
- Tamper, side-band attack and power loss detection with alerts
- Write-once OEM data page for supply chain authenticity

Specifications
Specifications for the three stocked DESI variants. Download the data sheet for the complete document.
| Parameter | DESI-IN | DESI-R | DESI-S |
|---|---|---|---|
| Function | |||
| Type | Dual input edge device for monitoring sensors | Single Form C relay output, N.O. and N.C. | Single Form A solid state relay output, N.O. |
| Rating | Dry contact, programmable rising or falling edge latch | SPDT, 120 VAC or 28 VDC at 12 A | SPST, 30 VDC at 2 A |
| Power monitoring | Not applicable | Remote power monitoring, alert on loss | Remote power monitoring, alert on loss |
| Cryptography | |||
| Standards | FIPS-186 ECDSA P256, FIPS-198 HMAC, NIST SP 800-90B, SHA-256 OTP, ECC-P256 | Same | Same |
| Key generation | On device, never exposed, or externally input | Same | Same |
| Rekeying | 4 root chain of trust rekeys; unlimited session rekeying | Same | Same |
| Tamper | Monitoring and alerts, active die shield, encrypted key storage | Same | Same |
| Physical | |||
| Form factor | 19.6 x 10.7 mm; shielded variant available | 44 x 20 mm | 28 x 16 mm |
| Connection | 6 in AWG 18 flying leads; braided shield drain on shielded | 6 in AWG 18 flying leads | 6 in AWG 18 flying leads |
| Mounting | Co-located with the sensing element | Co-located with the device | Co-located with the device |
| Environmental | -40 to 85°C | -40 to 85°C | -40 to 85°C |
| Deployment | |||
| Per panel | Up to 64 on a UFP-GW or EM-16, 32 on an EM-8, any mix | Same | Same |
| Per channel | 4 typical; more by application | Same | Same |
| Compliance | |||
| Safety | UL294, UL2610, UL62638-2, RoHS | Same | Same |
| Supply chain | Made in the USA, NDAA, TAA, BAA; globally unique identifier | Same | Same |
Videos
Walkthroughs and demonstrations for this product.
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DESI Controller video 1
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DESI Controller video 2
Downloads
Data sheet, brochure and specification documents for this product.
A&E resources · 3 available
Specification-ready files for this product. Download what you need without leaving the page.
Where it sits
DESI sits in Acquisition and Control, inches from the sensor or lock. It is where trust begins: the identity it supplies is what every layer above verifies.
- Enterprise Consumers Purdue 4 to 5
- IT and OT Operations Purdue 2 to 3
- Acquisition and ControlDESI Controller Purdue 1
- OT Edge Purdue 0
Questions about the DESI Controller?
Tell us what you are protecting and what is installed. Visit with a PSG systems engineer about configuration options and how it connects to your existing systems.


