Overview of MSTP

Definition

Multiple Spanning Tree Protocol (MSTP) defined in IEEE 802.1S. MSTP defines a VLAN mapping table in which VLANs are associated with multiple spanning tree instances (MSTIs). In addition, MSTP divides a switching network into multiple regions, each of which has multiple independent MSTIs. In this manner, the entire network is trimmed into a loop-free tree topology, and replication and circular propagation of packets and broadcast storms are prevented on the network. In addition, MSTP provides multiple redundant paths to balance VLAN traffic. MSTP is compatible with STP and RSTP.

Purpose

After an MSTP is configured on an Ethernet switching network, it calculates the network topology and implements the following functions to remove network loops:

Loop prevention: The potential loops on the network are cut off after redundant links are blocked.
Link redundancy: When an active path becomes faulty, a redundant link can be activated to ensure network connectivity.

Benefits

This feature offers the following benefits to carriers:

Compared with dual-homing networking, the ring networking requires fewer fibers and transmission resources. This reduces resource consumption.
MSTP prevents broadcast storms. This implements real-time communication and improves communication reliability.