3onedata IES615-1F-2DI, Руководство пользователя

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User Manual
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(Figure 5.9.3.1)
Rapid Spanning Tree of concepts:
Switch priority: As the bridge priority,the bridge priority and bridge MAC address combine bridge
ID,the smallest ID bridge will become the root bridge on the network.
Polling interval: how often send BPDU packet at one time.
Forwarding delay: the port state of switch remain a forward delay time over the listening and
learning.
The maximum aging time :after one switch receive a packet from other switches , how long the
packet is valid
The port concepts of RSTP:
Port path overhead: port link cost compared with port priority and port ID .
Port priority: port priority among the net bridge compared with port priority and port ID.
Point to point network connection: directly connect with switches port each other ,the port is
P2P,which adopted negotiation mechanism, RSTP can achieve port state rapid conversion RSTP.
Directly connect terminal: connect the edge of network switch with terminal devices with
configuration Edge port,which can achieve port state rapid conversion without the processing
Discarding,Learning,Forwarding.
Don’t join RST structure: Don‘t participate in RSTP running.
RSTP switch port states:
1. Blocking - A port that would cause a switching loop if it were active. No user data is sent or
received over a blocking port, but it may go into forwarding mode if the other links in use fail and the
spanning tree algorithm determines the port may transition to the forwarding state. BPDU data is still
received in blocking state. Prevents the use of looped paths.
2.
Listening - The switch processes BPDUs and awaits possible new information that would cause
it to return to the blocking state. It does not populate the MAC address table and it does not forward
frames.
3.
Learning - While the port does not yet forward frames it does learn source addresses from
frames received and adds them to the filtering database (switching database). It populates the MAC
Address table, but does not forward frames.
4.
Forwarding - A port receiving and sending data, normal operation. RSTP still monitors incoming
BPDUs that would indicate it should return to the blocking state to prevent a loop.