User Manual

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Users Manual of XGS-6350-24X4C
7. Edge port
In the RSTP protocol or MSTP protocol, edge port means the port directly connecting the network host. These
ports can directly enter the forwarding state without causing any loop in the network.
Figure 2.7 Edge port
In original state, MTSP and RSTP do not take all ports as edge ports, ensuring the network topology can be
rapidly created. In this case, if a port receives BPDU from other switches, the port is resumed from the edge
state to the normal state. If the port receives 802.1D STP BPDU, the port has to wait for double Forward
Delay time and then enter the forwarding state.
19.2.1.5 MSTP BPDU
Similar to STP and RSTP, switches running MSTP can communicate with each other through Bridge Protocol
Data Unit (BPDU). All configuration information about the CIST and MSTI can be carried by BPDU. Table 2.1
and Table 2.2 list the structure of BPDU used by the MSTP.
Table 2.1 MSTP BPDU
Field Name Byte Number
Protocol Identifier 1 – 2
Protocol Version Identifier 3
BPDU Type 4
CIST Flags 5