Characteristic 1 - Unidirectional communication

Controllers are strictly Unidirectional.

Ie the controller can keep a reference to the component to be controlled but at no point of time the reverse should be possible [which means component keeping a reference to the controller].

Why are controllers supposed to be unidirectional?

When we say that a controller keeps a reference to the component to be controlled ie that the controller can raise a request and a component is forced to respond to it.

Now if we allow the component to keep a reference to the controller, ie that component can raise a request and the controller will be forced to respond to it. Now ask yourself if we allow each and every component to keep a reference to the controller and the controller will be forced to respond to each of their requests, Can the controller control the system?

This is the reason, irrespective of the type of system or the stream of engineering … “Controllers are mostly unidirectional”.

I hope you will realize .. Can the law governing agencies or any city/state/country can be questioned ? Are we allowed to question the police?

Ask your self … if we allow the law governing agencies (including the police) to be questioned … that means all of us can raise a request and they will be forced to respond to each and every request , can they control the system effectively?

This is true for any kind of system including electrical systems, mechanical systems, social systems , software systems etc.

 
Hemant Jha
Founder - VPlanSolutions
Researcher, Trainer

www.VPlanSolutions.co.in