Question 7
A rogue switch has been added to your network, exchanged BPDUs, and is now part of the spanning tree topology.
Which feature would help prevent this from happening in the future?
Correct answer: B
Explanation:
EX Series switches support spanning-tree protocols that prevent loops in a network by creating a tree topology (spanning-tree) of the entire bridged network. All spanning-tree protocols use a special type of frame called bridge protocol data units (BPDUs) to communicate with each other. When BPDUs generated by other devices are transmitted to switches on which spanning-tree protocols are configured, a misconfiguration can occur in the spanning tree and a network outage can occur. Therefore, it is necessary to protect an interface in a spanning-tree topology from BPDUs generated from other devices. http://www.juniper.net/documentation/en_US/junos13.3/topics/task/configuration/spanning-trees-bpdu-block-cli.html
EX Series switches support spanning-tree protocols that prevent loops in a network by creating a tree topology (spanning-tree) of the entire bridged network. All spanning-tree protocols use a special type of frame called bridge protocol data units (BPDUs) to communicate with each other.
When BPDUs generated by other devices are transmitted to switches on which spanning-tree protocols are configured, a misconfiguration can occur in the spanning tree and a network outage can occur. Therefore, it is necessary to protect an interface in a spanning-tree topology from BPDUs generated from other devices.
http://www.juniper.net/documentation/en_US/junos13.3/topics/task/configuration/spanning-trees-bpdu-block-cli.html