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MultipleSpanningTreeProtocol(MSTP)denedinIEEE
802.1s, enables multiple VLANs to be mapped to redu-
cethe number of spanning-tree instances needed to sup-
port a large number of VLANs. If there is only one VLAN
in the network, a single STP works appropriately.
If the network contains more than one VLAN however,
thelogicalnetworkconguredbyasingleSTPwould
work,butitbecomesmoreefcenttousethealternate
paths available by using an alternate spanning tree for
different VLANs or groups of VLANs. MSTP (which is
based on RSTP for fast convergence) is designed to sup-
port independent spanning trees based on VLAN groups.
MSTPprovidesmultipleforwardingpathsfordatatrafc
and enables load balancing.
STP and RSTP prevent loops from forming by ensuring
that only one path exists between the end nodes in your
network. RSTP is designed as a general replacement for
the slower, legacy STP. RSTP is also incorporated into
MSTP. With STP, convergence can take up to a minute to
complete in a larger network. This can result in the loss
of communication between various parts of the network
during the convergence process so STP can subsequent-
ly can lose data packets during transmission.
RSTP on the other hand is much faster than STP. It can
complete a convergence in seconds, so it greatly dimin-
ishes the possible impact the process can have on your
network compared to STP. RSTP reduces the number of
state changes before active ports start learning, pre-
deninganalternateroutethatcanbeusedwhena
node or port fails and retain the forwarding database for
ports insensitive to changes in the tree structure when
recongurationoccurs.
Select whether to Enable or Disable the Spanning Tree
function for the Switch. Next, select whether you wish
to enable STP, RSTP, or MSTP. Again, please note that
only one Spanning tree function can be active at a time.
Apply: Click APPLY to update the the system settings.
