802.1s Multiple Spanning Tree Protocol

Multiple Spanning Tree Protocol (MSTP), as defined in IEEE 802.1s, allows multiple VLANs to be managed by a single STP instance and supports per-VLAN STP. As a result, several VLANs can be mapped to a reduced number of spanning-tree instances. This ensures loop-free topology for one or more VLANs that have the similar layer-2 topology. The RUCKUS implementation supports up to 16 spanning tree instances in an MSTP enabled bridge which means that it can support up to 16 different Layer 2 topologies. The spanning tree algorithm used by MSTP is RSTP which provides quick convergence.