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Cisco Small Business 200 1.1 Series Smart Switch Administration Guide
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Configuring the Spanning Tree Protocol
The Spanning Tree Protocol (STP) (IEEE802.1D and IEEE802.1Q) is enabled by
default, set to RSTP (Rapid Spanning Tree Protocol) mode, and protects a Layer 2
Broadcast domain from broadcast storms by selectively setting links to standby
mode to prevent loops. In standby mode, these links temporarily do not transfer
user data. They are automatically re-activated when the topology changes to
make it desirable to transfer user data.
This section contains the following topics:
•
STP Flavors
•
Configuring STP Status and Global Settings
•
Defining Spanning Tree Interface Settings
•
Configuring Rapid Spanning Tree Settings
STP Flavors
Loops occur when alternate routes exist between hosts. Loops in an extended
network can cause Layer 2 switches to forward traffic indefinitely, resulting in
increased traffic and reduced network efficiency.
STP provides a tree topology for any arrangement of Layer 2 switches and
interconnecting links, creating a unique path between end stations on a network,
eliminating loops.
The switch supports the following Spanning Tree Protocol versions:
•
Classic STP provides a single path between any two end stations, avoiding
and eliminating loops.
•
Rapid STP (RSTP) detects network topologies to provide faster
convergence of the spanning tree. This is most effective when the network