The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 13, 1990
Filed:
Oct. 28, 1987
Boris D Lubachevsky, Bridgewater, NJ (US);
American Telephone and Telegraph Company AT&T Bell Laboratories, Murray Hill, NJ (US);
Abstract
A discrete event simulation system that avoids all blocking and advances the simulation time in an efficient manner by treating the simulated system as a set of subsystems and simulating the subsystems concurrently. The simulation proceeds iteratively by restricting the simulation of scheduled events for each subsystem at any one time to a chosen simulated time segment (bounded lag) beginning with the lowest simulation time found among the subsystems. With each simulation iteration, an 'at risk', demarcation time is evaluated based only on a subset of the subsystems that can potentially affect the simulation at the considered subsystem. Events scheduled for a time earlier than the 'at risk' time are simulated. In simulating systems where some subsystems affect other subsystems only through intermediate subsystems, opaque periods can be experienced when, because of the specific process that is being simulated, such an intermediate subsystem 'promises' that a particular route emanating from this subsystem would be busy for a set period of time, and thereby also 'promises' that no other subsystem can use this route as a conduit to affect other subsystems. That tends to push forward the 'at risk' demarcation time.