OSDP: The Security Industry Association's new Open Supervised Device Protocol
The Open Supervised Device Protocol (OSDP) is an access control communication protocol recently adopted by the Security Industry Association (SIA) to improve interoperability among access control and security products. OSDP became an international IEC standard in 2020.
Compared to its Wiegand predecessor, the emerging OSDP standard offers:
- More Security: OSDP v2 with Secure Channel protects readers against hacking using AES-128 encryption.
- More Functionality: OSDP uses 2 wires instead of 10+, allows for multi-drop installation, supervises connections to indicate reader malfunctions, is scalable to connect more field devices, and more.
- More Interoperability: Using OSDP enables communication among different manufacturers' devices.
- More Consistency: Not only does OSDP provide a concise set of commonly used commands and responses, it eliminates guesswork, since encryption and authentication are predefined.
OSDP specifically applies to peripheral devices (PDs) such as card readers and other devices at secured access doors/gates and their control panels (CPs).
With OSDP, all the functions which used to require 12 or more physical wires between the door location and the access control panel (including wires for the card reader, door strike, alarm contact, and Request to Exit functions) can be fully implemented using just 2 wires.
The OSDP specification is recommended when TCP/IP, USB, or other common protocols do not lend themselves to the application. A primary advantage of OSDP is the low cost of implementation in an embedded device.