STP Interview Questions

• What is Spanning tree aka STP ?
• How does STP maintain a loop-free network?
• What parameters can be tuned to influence the selection of a port as a Root or Designated Port?
• What is BDPU ?what is the basics function of BPDU?
• What is the STP listening state?
• Which command enables RSTP on a switch?
• what is Per-VLAN Spanning Tree Protocol (PVST)
• What is the default bridge priority in a Bridge ID for all Cisco switches?
• Which STP version run default on cisco switches ?
• What is the purpose of Spanning Tree Protocol in a switched LAN?
• Difference between Spanning Tree Protocol (STP) and Rapid Spanning Tree Protocol (RSTP)?
• What is the STP blocking state?
• What is the STP Forwarding state?
• Difference between Root Port and Designated Port?
• What is the difference between path cost and root path cost?
• What is the difference between STP, MSTP, PVST and RSTP?
• What is path cost?
• Define selection criteria of STP root bridge.
• What are the four spanning tree port states?
• How do non root bridge decide which port will elect as root port?
• If a non root bridge has two redundant ports with the same root path cost,
• how does the bridge choose which port will be the root port?
• Port states of spanning tree protocol.
• If the users face delay during initial login, what you will suggest to implement?
• Why spanning tree BPDU filter is used?
• Can I use BPDU filter on trunk ports?
• Which port state is introduced by Rapid-PVST?
• What is Spanning Tree Protocol (STP) PortFast?
• What does STP do when it detects a topology change in the network due to a bridge or link failure?
• What is the reason for developing another version STP i.e. RSTP?
• Can STP be configured on a router?
• Is STP required to be configured when there is only one switch involved.
• Is a generic ethernet frame modified when STP is configured on the network
• How many designated ports can be available on a root bridge
• How many root bridges can be available on a STP configured network
• If the priority value of the two switches are same, which switch would be elected as the root bridge
• What is the basic purpose of the BPDUs and STA?
• What is Configuration BPDU?
• What is the destination MAC address used by Bridge Protocol Data Units (BPDUs)?
• What is TCN BPDU?
• What is TCA BPDU?
• What is Bridge Protocol Data Unit (BPDU) Frame Format?
• What is Path Cost or Spanning Tree Path Cost value?
• What is Root Port?
• What is Spanning Tree Port ID?
• What is PVST or PVST+?
• What is Extended System ID?
• What are STP Timers and Explain different types of STP Timers?