IS5 COMMUNICATIONS iES22GF, Руководство пользователя

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iES22GF User’s Manual
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iS5 Communications Inc.
5.4 STP/RSTP/MSTP
5.4.1 STP/RSTP
STP (Spanning T r e e Protocol), and its ad van ced v e r s io n s RSTP (Rapid Spanning Tree Protocol)
and MSTP (Multiple Spanning Tree Protocol), are designed to prevent network loops and provide
network redundancy. Network loops occur frequently in large networks when two or more paths run
to the same destination, broadcast packets could get in to an infinite loop and cause congestion in the
network. STP can identify the best path to the destination and block all other paths. The blocked links
will stay connected but inactive. When the best path fails, the blocked links will be activated.
Compared to STP which recovers a link in 30 to 50 seconds, RSTP can shorten the time to 5 to 6
seconds.
STP Bridge Status
This page shows the status for all STP bridge instance.
Label Description
M STI
The bridge instance. Can also be linked to the STP detailed bridge status.
Bridge ID The bridge ID of this bridge instance.
Root ID The bridge ID of the currently selected root bridge.
Root Port
The switch port currently assigned the root port role.
Root Cost
Root path cost. For a root bridge, this is zero. For other bridges, it is the
sum of port path costs on the least cost path to the Root Bridge.
Topology Flag
The current state of the Topology Change Flag for the bridge instance.
Topology
Change Last
The time since last Topology Change occurred.
Refresh
Click to refresh the page immediately.
Auto-refresh
Check this box to enable an automatic refresh of the page at regular
intervals.
STP Port Status