Which of the following is NOT an advantage of star topology compared to other…

Concept: In a star topology every node connects through its own dedicated cable to a single central device (a hub or switch). All advantages and disadvantages of the star flow from this one central-point structure: management, fault isolation and adding nodes become easy, but the wiring effort and the dependence on the centre both grow.

Application: The question asks which listed property is NOT a benefit. Because each node needs a separate run of cable back to the centre, the total cabling for a star is larger than for a shared-medium layout such as bus, where all nodes tap one common backbone. So "requires less cable length" describes the opposite of reality and is therefore NOT an advantage.

Contrast with the genuine advantages:

• Adding a new node only means running one cable to the central device, leaving every other node undisturbed — a real advantage.

• Each node having its own direct link to the central device simplifies management and keeps one node's traffic off the others — a real advantage.

• A faulty node or its single cable can be isolated at the centre without taking down the rest of the network — a real advantage.

• More total cable length, however, is an extra cost the star pays for that centralised structure — so it is a drawback, not a benefit.

Cross-check: Note that the central device being a single point of failure is also a real disadvantage of the star, but it is not among the listed choices; among the four given, only the cable-length claim is falsely presented as an advantage.