14.
Multiple Spanning Tree Protocol (MSTP)
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designated switch. Also, a switch might continue to assign a boundary role to a port when the
switch 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 if
they are RSTP BPDUs. Therefore, MSTP switches send either a version 0 configuration and
TCN BPDUs or version 3 MSTP BPDUs on a boundary port. A boundary port connects to a
LAN, the designated switch of which is either a single spanning-tree switch or a switch with a
different 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 number
of VLANs by using VLAN grouping.
•
MSTP provide rapid convergence, which can reduce link convergence time to less than
two seconds.
•
MSTP continues operating without loops in any physical connection topology including
shared spanning tree switches, 802.1Q mono spanning tree switches, and others.
Supported Standards, MIBs and RFCs
Standards
IEEE 802.1D-1998
IEEE 802.1W-2001
IEEE 802.1S-2002
MIBs
Private MIB,
batm_mst.mib
RFCs
No RFCs are supported by this feature.