What is a characteristic of spanning tree?
- It is enabled by default on Cisco switches.
- It has a TTL mechanism that works at Layer 2.
- It prevents propagation of Layer 2 broadcast frames.
- It is used to discover information about an adjacent Cisco device.
Answers Explanation & Hints: Spanning tree does work at Layer 2 on Ethernet-based networks and is enabled by default, but it does not have a TTL mechanism. Spanning tree exists because Layer 2 frames do not have a TTL mechanism. Layer 2 frames are still broadcast when spanning tree is enabled, but the frames can only be transmitted through a single path through the Layer 2 network that was created by spanning tree. Cisco Discovery Protocol (CDP) is used to discover information about an adjacent Cisco device.