User manual
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wEb-bASED bROwSER MANAGEMENT
• While providing a much better performance than STP, IEEE 802.1w RSTP still .
required up to a few seconds to restore network connectivity when a topology
change occurred. A revised and highly optimized RSTP version (which this switch
supports) was dened in the IEEE standard 802.1D-2004 edition and now reduces
network recovery times to just milliseconds.
RSTP States and Roles
RSTP bridges have roles to play, being either root or designated. One bridge, the
root bridge, is the logical center of the network. All other bridges in the network are
designated bridges. RSTP also assigns each port of the bridge a state and a role.
The RSTP state describes what is happening at the port in relation to address
learning and frame forwarding. The RSTP role basically describes whether the
port is facing the center or edges of the network and whether it can currently be
used or not.
There are three RSTP states: discarding, learning and forwarding.
The discarding state is entered when the port is rst taken into service. The port
does not learn addresses in this state and does not participate in frame transfer.
The port looks for RSTP trafc in order to determine its role in the network. When
it is determined that the port will play an active part in the network, the state will
change to learning.
The learning state is entered when the port is preparing to act as an active member
of the network. The port learns addresses in this state but does not participate in