A method and system determines a location of a device by first measuring, in a receiver of the device, received signal strength levels of reference signals transmitted by a set of access points arranged in an enclosed environment. For example, each of multiple processes utilizes current and past data values associated with a global counter or clock for purposes of determining whether any shared variables used to produce a respective transaction outcome were modified when executing a respective transaction. However, exponential back-off can create an exponential increase in the transmit latency. The generation pattern description storing unit stores the generation pattern description for structuring the information obtained from the class definition.