{{commons category|Multiple Spanning Tree Protocol}}
The '''Multiple Spanning Tree Protocol''' ('''MSTP''') and [[algorithm]], provides both simple and full connectivity assigned to any given [[Virtualvirtual LAN]] (VLAN) throughout a Bridgedbridged Local[[local Areaarea Networknetwork]]. MSTP uses [[Bridgebridge Protocolprotocol Datadata Unit|BPDUsunit]] (BPDUs) to exchange information between spanning-tree compatible devices, to prevent loops in each [[Multiple Spanning Tree Protocol#Multiple Spanning Tree Instances (MSTI)|MSTI]] (Multiple Spanning Tree Instancesinstance]] (MSTI) and in the [[Multiple Spanning Tree Protocol#Common and Internal Spanning Tree (CST/CIST)|CIST]] (Commoncommon and Internalinternal Spanningspanning Treetree]] (CIST), by selecting active and blocked paths. This is done as well as in [[Spanning Tree Protocol|STP]] (STP) without the need of manually enabling backup links and getting rid of [[switching loop]] danger.
Moreover, MSTP allows frames/packets assigned to different VLANs to follow separate paths, each based on an independent MSTI, within MST Regionsregions composed of [[Locallocal area network|networks (LANs]] ) and or MST Bridgesbridges. These Regionsregions and the other Bridgesbridges and LANs are connected into a single Commoncommon Spanningspanning Treetree (CST).
