What Are The Benefits Of OSDP Vs Weigand?
OSDP Vs Weigand – Open Supervised Device Protocol (OSDP) is an access control communications standard developed by SIA to improve access control interoperability and security between readers and access controllers.
Importantly, OSDP was approved as an international standard by the International Electrotechnical Commission in May 2020 and published as IEC 60839-11-5. SIA OSDP v2.2, which is based on the IEC 60839-11-5 standard, was released in December 2020 and the standard is constantly evolving.
Even more importantly, the OSDP specification is extensible to IP environments and the OSDP Working Group is in the process of deploying OSDP over IP, with a release expected soon. OSDP is used by a wide range of access control manufacturers and its capabilities make it especially appealing for high security applications.
There’s a sound argument that OSDP should also be used in a wider spread of applications, given the Weigand alternative offers no security between reader and controller, though it does offer installers several advantages.
When it comes to security, the OSDP secure channel is AES-128 encrypted for government applications and is constantly monitored to protect against line attacks.
The original Weigand technology allowed 8 bits for site codes and 16 bits for card codes – it goes without saying this was inadequate and most makers developed code variations which peaked at around 37 bits – common formats include 26-bit and 32-bit. That’s a fair bit more in raw terms but trivial compared to AES-128, which is itself a surpassed encryption standard.
OSDP also supports advanced smartcard technology applications, including PKI/FICAM and biometrics, and offers bi-directional communications among devices. The OSDP standard supports advanced user interface, including welcome messages and text prompts.
What Are The Benefits Of OSDP Vs Weigand
OSDP’s use of 2 wires allows for multi-drop installations and supervised connections to indicate reader malfunctions, as well as delivering scalability to connect more field devices – these are sound pieces of functionality.
Regardless, there’s ongoing debate around the use of OSDP or Weigand in some applications, with installers and integrators arguing Weigand serves internal readers in secure spaces perfectly well offering some security and a lot of cost effectiveness.
Weigand runs on a pair of wires and has the advantage of allowing very long cable runs – more than 150 metres. It’s a simple and flexible protocol to install and supports a wide range of reader technologies – from swipe cards to biometrics.
Perhaps the biggest benefit of Weigand is that it’s widely device agnostic. There are some applications and some installation businesses which would highly value this quality.
Weigand is more vulnerable to tampering than OSDP and it’s more vulnerable to environmental noise, too. And while Weigand is simple to program it can be harder to trouble shoot in a complex application.
In mid and higher security applications, OSDP – or a proprietary standard of similar or superior performance – may be the best choice, especially if your favoured access control solution supports it, and even more especially if you have multiple external readers.
According to Gallagher’s Steve Bell, OSDP open standard should be considered the minimum standard communications protocol for card readers but only when its encryption is properly implemented and managed by the system.
“At Gallagher, we are designing our hardware and communications protocols to meet the needs of the highest security customers,” Bell says. “Before OSDP was widely adopted, Gallagher set about designing our own reader communications protocol called HBUS.
“This solution achieves the highest levels of authentication and performance with very fast communications, where the use of public key credentials can still deliver a frictionless experience for the user.”
Benjamin Cho of vehicle reader specialist Nedap believes OSDP and technologies like it are the way of the future.
“Wiegand is not as secure, and also its single-direction communication does not allow for efficient management of readers,” Cho said.
“What Are The Benefits Of OSDP Vs Weigand?”