Distributed one-time-use entry code generation for physical access control method of operation and mobile systems

A method for control of a physical access portal comprising the processes:

• at a controller,
• receiving a plurality of physical access requests (access requests) from a plurality of mobile application devices;
• at the controller,
• determining for each mobile application device (app device) a sequence of access requests comprising at least a first access request and a second access request SOLELY GENERATED BY EACH mobile application DEVICE;
• at the controller, upon authenticating the first access request (predecessor), writing into non-transitory storage a one-time verification code specific to an immediately subsequent second access request (successor) from the same mobile application device;
• and at the controller,
• upon receiving a successor, performing an authentication process by matching the stored one-time verification code associated with the predecessor;
• and
• on the condition the authentication process passes, writing a newer one-time verification code into non-transitory storage specific to yet another immediately subsequent successor;
• wherein each newer one-time verification code is synthesized WITH A MASK OF LEAST SIGNIFICANT BITS TO PROVIDE A RANGE OF TIME RELATING A REQUEST AND THE LAST SUCCESSFUL PHYSICAL ACCESS REQUEST SOLELY AT AND by the mobile application device and transmitted in both a predecessor and successor request;
• and,
• on the condition the authentication process fails,
• setting a flag of questionable chain of control associated with the mobile application device.