OSDP an acronym for Open Supervised Device Protocol is the recent trend of communication protocol in access control systems. The protocol is developed by SIA (Security Industry Association) of United States of America to improve the security and interoperability in widely used security products, this way eliminating the bugs and drawbacks of Wiegand protocol that is part of industry since decades.
Simply it is very secure protocol. OSDP, approved by International Electro technical Commission approved as an international standard and was published as IEC 60839-11-5 in July 2020. Being secure, it is widely recommended for high secure application as per industry standards. In terms of security and functionality, the advantages of Open Supervised Device Protocol are listed as below
| Encryption | High end AES 128 |
| Monitoring | Constant monitoring to protect against threats |
| Smart cards | Supports smart card technology, PKI, FICAM, Biometrics |
| Interfaces | Advanced user interface, welcome messages, text prompts |
| Wires | 2 |
| Interoperability | Communications among manufacturers, solutions & devices |
There are two levels of Open Supervised Device Protocol viz.a.viz. OSDP V1 & OSDP V2. OSDP V2 is superset of OSDP V1 and has secure channel encryption, smart card communication with biometric reader support, timeout near 200ms, and busy port reply. Secure channel is an encryption technique used by OSDP V2 compliant devices to protect the communication between controllers and readers.
The recommended wire specifications for Open Supervised Device Protocol must be compliant with TIA 485/ EIA-RS485. In general Open Supervised Device Protocol supports bi-directional communication between controller & reader, beep & LED control, with maximum data size unto 1024 bytes, communication encryption and daisy chain cabling.