Configuring MSTP
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23.3 Algorithm Implementation
23.3.1 MSTP Protocol
MST BPDU packet format as below:
Figure 23-8 MSTP PDU protocol packet
Protocol Identifier: is 0x0000, identifies the Spanning Tree Protocol (2 bytes).
Protocol Version Identifier: as the 0x03, identifies the protocol version (1 byte).
BPDU Type: for the 0x02, that RST BPDU (1 byte).
CIST Flags: identify the CIST topology change confirmation, consent, forwarding,
learning, port role, suggested that the topology change state (1 byte).
CIST Root Identifier: CIST root bridge's unique identifier, by the CIST root bridge of
It is the similar of FoxGate region and red
region of the message format and SST;
Version 3 Length indicates the length of
the blue area;
Version 3 Length indicates the length of
the blue area
；
RSTP is defined with the Flags field is
similar to but MSTI Flags of the highest
bit is the main port identification, while
the highest is the CIST Flags TCA logo.
