PrepAway - Latest Free Exam Questions & Answers

Based on the details provided, which three statements are correct? (Choose three.)

Refer to the Exhibit.

As shown in the exhibit, three switches are connected and participating in RSTP. Switch-1 was elected the root bridge and Switch-2 has a lower-cost path to the root bridge than Switch-3. Based on the details provided, which three statements are correct? (Choose three.)

PrepAway - Latest Free Exam Questions & Answers

A.
Switch-3’s ge-0/0/10.0 port assumes the alternate role and blocking state.

B.
Switch-3’s ge-0/0/10.0 port assumes the designated role and forwarding state.

C.
Switch-2’s ge-0/0/10.0 port assumes the designated role and forwarding state.

D.
Switch-1’s ports all assume the root port role and the forwarding state.

E.
Switch-1’s ports all assume the designated port role and the forwarding state.

Explanation:
Peer STP applications running on switch interfaces exchange a special type of frame called a bridge protocol data unit (BPDU). Switches communicate interface information using BPDUs to create a loop-free topology that ultimately determines the root bridge and which interfaces block or forward traffic in the spanning tree.

However, a root port elected through this process has the possibility of being wrongly elected. A user bridge application running on a PC can generate BPDUs, too, and interfere with root port election.

To prevent this from happening, enable root protection on interfaces that should not receive superior BPDUs from the root bridge and should not be elected as the root port. These interfaces are typically located on an administrative boundary and are designated ports.

When root protection is enabled on an interface:

* The interface is blocked from becoming the root port.
* Root protection is enabled for all STP instances on that interface.
* The interface is blocked only for instances for which it receives superior BPDUs. Otherwise, it participates in the spanning-tree topology.


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