There has been a lot of talk in the The Continental Automated Building Association (CABA) in Cisco Connected Commercial Real Estate (CCRE) and other venues about the collapsing of building wiring plans into a single wiring plan that handles all communications, whether within the building systems, or for voice communications, or for computer networking. The presumptive protocol for all this is IP (as in TCP/IP).
Superficially, this is a compelling vision. Certainly the combination of Voice and Data networking is well under way. Wiring is a large part of the systems expense for every building. Reducing the number of wiring systems offers opportunities for cost reduction.
I have trouble putting the components of building systems in this category. I think each building systems provide an integrated service. Defending and supporting the provision of that service is the mission of each system. Components of that system do not really make sense outside of that system. Defining security for these system components is nonsensical.
Security and Access can only reasonably be defined at the level of the service. What is the security posture for a sensor that reveals an unidentified temperature? What does the value of a sensor mean if isolated from its system. How can we define access to a setpoint if that setpoint is isolated from the service it controls?
One counterpoint might be if the wiring went beyond networking to provision of power. This might reduce cost enough to make such systems worth-while. I do not know if anyone is using Power Over Ethernet (POE) to reduce the wiring costs of sensors or actuators.
Is anyone using POE to power sensors or actuators within a control system? Can onyone point out to me anyone whi is actually doing POE to control systems? Or does this entire field remain in the realm of “marketecture”.