問題文
A pair of access switches is cabled to two aggregation switches with four links in a square. Spanning tree is running. What does the protocol accomplish here?
選択肢
- It elects one link as the reference point and forwards every frame over that link, so that the square is used as a single path whose capacity does not change.
- It bundles the four links into one logical link and spreads the frames across them, so that the square is used at its full aggregate capacity.
- It elects one device as the reference point and puts some links into a state that does not forward, so that the frames cannot circulate endlessly.
- It assigns a separate broadcast scope to some of the links and keeps them isolated, so that a frame entering one link cannot leave it.