Siemens S323 User Manual

User Manual                                                                               UMN:CLI 
SURPASS hiD 6615 S223/S323 R1.5 

A50010-Y3-C150-2-7619                                                                         201 

Meanwhile, RSTP (Rapid Spanning-Tree Protocol) defined in IEEE 802.1w innovate re-
duces the time of network convergence on STP (Spanning-Tree Protocol). It is easy and 
fast to configure new protocol. 

Also, 802.1w includes 802.1d inside, so it can provide compatibility with 802.1d. For more 
detail description of STP and RSTP, refer to the following. 

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The 802.1d STP defines port state as blocking, listening, learning, and forwarding. When 
STP is configured in LAN with double-path, switches exchange their information including 
bridge ID. It is named as BPDU (Bridge Protocol Data Unit). Switches decide port state 
based on the exchanged BPDU and automatically decide optimized path to communicate 
with the root switch. 
 

The most important information to decide the root switch is bridge ID. Bridge ID is com-
posed of 2 bytes-priority and 6 bytes-MAC address. The root switch is decided with the 
lowest bridge ID. 

 

Root Switch