Within an MST region, the packet is forwarded along the corresponding MSTI.
Between two MST regions, the packet is forwarded along the CST.
Implementation of MSTP on Devices
MSTP is compatible with STP and RSTP. STP and RSTP protocol packets can be recognized by
devices running MSTP and used for spanning tree calculation.
In addition to basic MSTP functions, many special functions are provided for ease of management, as
follows:
Root bridge hold
Root bridge backup
Root guard
BPDU guard
Loop guard
TC-BPDU guard
BPDU dropping
Protocols and Standards
MSTP is documented in:
IEEE 802.1d: Spanning Tree Protocol
IEEE 802.1w: Rapid Spanning Tree Protocol
IEEE 802.1s: Multiple Spanning Tree Protocol
MSTP Configuration Task List
Before configuring MSTP, you need to know the role of each device in each MSTI: root bridge or leave
node. In each MSTI, one, and only one device acts as the root bridge, while all others as leaf nodes.
Complete these tasks to configure MSTP:
Configuring
the root bridge
Configuring an MST Region
Configuring the Root Bridge or a Secondary Root Bridge
Configuring the Work Mode of an MSTP Device
Configuring the Priority of a Device
Configuring the Maximum Hops of an MST Region
Configuring the Network Diameter of a Switched Network
Configuring Timers of MSTP
Configuring the Timeout Factor
Configuring the Maximum Port Rate
Configuring Ports as Edge Ports
Configuring the Link Type of Ports
Configuring the Mode a Port Uses to Recognize/Send MSTP Packets
Enabling the Output of Port State Transition Information
Task
1-15
Remarks
Required
Optional
Optional
Optional
Optional
Optional
Optional
Optional
Optional
Optional
Optional
Optional
Optional