HP ProCurve 9304M Installation And Configuration Manual page 239

Handshake When a Root Port Has Been Elected
If a non-root bridge already has a Root port, 802.1W uses a different type of handshake. For example, in Figure
8.8, a new root bridge is added to the topology.
Fig u r e 8 . 8 A ddit i on of a N e w R oot B r idg e
Switch 200
Port2
Switch 300
Configuring Spanning Tree Protocol (STP) and Advanced STP Features
Switch 100
Port2
Port1
Designated port Designated port
Port1
Root port
Port4
Port2
Port3
Port3
Port2
Designated
port
Port4
Designated port
Switch 400
Switch 60
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