Examkin

Soru

Zorluk: OrtaSpanning Tree Protocol Operations

A network interface on a switch configured with IEEE 802.1D Spanning Tree Protocol (STP) experiences a link bring-up event. In what sequence does the port transition through its operational states from initial activation until it actively processes and forwards end-user network traffic? Place the STP port states in chronological order from first to last.

  1. 1Blocking State
  2. 2Listening State
  3. 3Learning State
  4. 4Forwarding State

Cevap

The correct chronological sequence of IEEE 802.1D STP port states from initial link activation to full operation is: Blocking State, Listening State, Learning State, and Forwarding State.
In IEEE 802.1D STP, a switch port bringing up a link progresses strictly through Blocking → Listening → Learning → Forwarding. First, it starts in Blocking to listen for BPDUs without causing loops. Next, it moves to Listening to elect the Root Bridge and designate port roles. Then, it transitions to Learning to build MAC address tables without sending data. Finally, it enters Forwarding for normal data traffic.

Adım Adım Çözüm

1
Identify the initial state upon link up
The port begins in the Blocking state to avoid network loops while waiting to receive BPDU traffic.
Default safety mechanism in 802.1D ensures ports do not forward data before knowing network topology.
2
Determine the STP election and topology evaluation phase
The port transitions from Blocking to the Listening state after the forward delay timer.
In Listening, the switch transmits and receives BPDUs to determine Root Bridge and port roles without learning MAC addresses or forwarding data.
3
Identify the MAC table population phase
The port transitions from Listening to the Learning state.
In Learning, the port populates its MAC address table from frame headers to prepare for frame forwarding, though user data forwarding remains disabled.
4
Identify the final fully operational phase
The port transitions from Learning to the Forwarding state.
The port now actively transmits and receives data frames, having safely passed all STP convergence convergence timers.

Anahtar Kavram

IEEE 802.1D Spanning Tree Protocol (STP) Port State Convergence Progression
Bu soruyu puanla

Konular

Spanning Tree Protocol Operations

Bu konudan daha fazla soru