14. Multiple Spanning Tree Protocol (MSTP)MN700004 Rev 01 147designated switch. Also, a switch might continue to assign a boundary role to a port when theswitch to which it is connected has joined the region.If all the legacy switches on the link are RSTP switches, they can process MSTP BPDUs as ifthey are RSTP BPDUs. Therefore, MSTP switches send either a version 0 configuration andTCN BPDUs or version 3 MSTP BPDUs on a boundary port. A boundary port connects to aLAN, the designated switch of which is either a single spanning-tree switch or a switch with adifferent MST configuration.Benefits• MSTP enables load balancing, over a large number of VLANs.• MSTP reduces the number of spanning-tree instances required to support a large numberof VLANs by using VLAN grouping.• MSTP provide rapid convergence, which can reduce link convergence time to less thantwo seconds.• MSTP continues operating without loops in any physical connection topology includingshared spanning tree switches, 802.1Q mono spanning tree switches, and others.Supported Standards, MIBs and RFCsStandardsIEEE 802.1D-1998IEEE 802.1W-2001IEEE 802.1S-2002MIBsPrivate MIB, batm_mst.mibRFCsNo RFCs are supported by this feature.
