Ccna certification Practice Tests

300

 

Appendix 

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  Answers to Practice Test Questions

 134.  A.  Every switch in the network segment must have at least one root port. This is the port 

that leads back to the root bridge. The root bridge will have a designated port on the 

adjacent link. Every switch will have an active link back to the root bridge; however, those 

ports leading back the root bridge are called root ports. A network may not have any 

alternate ports, depending on the topology and layout of the network. A network may not 

have any backup ports for the same reasons.

 135.  C.  The root port is the port that leads back to the root bridge on the adjacent switch. It 

has the lowest cost of the redundant ports. A root port is determined to have the lowest 

cost to the root bridge, not a network segment. Root ports are always determined to have 

the lowest cost, not the highest cost.

 136.  A.  The designated port is the port with the lowest cost of the redundant links to the 

network segment. The adjacent port is normally the root port leading back to the root 

bridge. A port that is determined to have the lowest cost or path cost to the root bridge is 

called the root port and not a designated port. The designated port will always have the 

lowest cost to a network segment, not the highest cost.

 137.  C.  The PVST+ bridge ID comprises a 4-bit bridge priority calculated in blocks of 4096, a 

12-bit sys-ext-id that is the VLAN ID for the segment, and a 6-byte MAC address for the 

switch. All of the other options are incorrect.