Choke point
In military strategy, a choke point (or chokepoint) is a geographical feature on land such as a valley, defile or a bridge, or at sea such as a strait which an armed force is forced to pass, sometimes on a substantially narrower front, and therefore greatly decreasing its combat power, in order to reach its objective. A choke point would allow a numerically inferior defending force to successfully prevent a larger opponent because the attacker would not be able to bring their superior numbers to bear.
https://military-history.fandom.com/wiki/Choke_point
also a term used in computer systems
Choke Point
In subject area:
Computer Science
A choke point is a limited interface point between zones that is carefully monitored and controlled to restrict movement and access, making it easier to manage and secure data flow in a computer system.
https://www.sciencedirect.com/topics/computer-science/choke-point