Huawei Quidway S3000 Series Operation Manual page 4

Operation Manual - STP
Quidway S3000 Series Ethernet Switches
Switch B
Figure1-1 Designated switch and designated port
For a switch, the designated switch is a switch in charge of forwarding packets to the
local switch via a port called the designated port accordingly. For a LAN, the designated
switch is a switch that in charge of forwarding packets to the network segment via a port
called the designated port accordingly. As illustrated in the figure1-1, Switch A forwards
data to Switch B via the port AP1. So to Switch B, the designated switch is Switch A and
the designated port is AP1. Also in the figure above, Switch B and Switch C are
connected to the LAN and Switch B forwards packets to LAN. So the designated switch
of LAN is Switch B and the designated port is BP2.
Note:
AP1, AP2, BP1, BP2, CP1 and CP2 respectively delegate the ports of Switch A, Switch B and Switch C.
The specific calculation process of STP algorithm.
The following example illustrates the calculation process of STP.
The figure1-2 below illustrates the network.
Switch A
AP1 AP2
BP1
Switch C
BP2
LAN
CP1
CP2
1-2
Chapter 1 RSTP Configuration