The term comes from logistics, and in the literal sense it means a physical operation (action or process) that restricts the flow of materials into or through a system. In the abstract sense it means a process or activity that restricts the flow of something into or through a system.

A simple everyday example of a gating operation is a traffic light on a freeway access ramp that allows only one car at a time to enter the freeway, in order to avoid traffic jams from an excessive inflow of traffic.

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Drum-Buffer-Rope (DBR): In the theory of constraints, the generalized process used to manage resources to maximize throughput. The drum is the rate or pace of production set by the system’s constraint. The buffers establish the protection against uncertainty so that the system can maximize throughput. The rope is a communication process from the constraint to the gating operation that checks or limits material released into the system to support the constraint. Also see: Finite Scheduling
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