Chapter 14: Spanning Tree; Stp Flavors - Cisco SF500-24 Administration Manual

Spanning Tree

STP Flavors

Cisco 500 Series Stackable Managed Switch Administration Guide Release 1.3
This section describes the Spanning Tree Protocol (STP) (IEEE802. 1 D and
IEEE802. 1 Q) and covers the following topics:
• STP Flavors
• Configuring STP Status and Global Settings
• Defining Spanning Tree Interface Settings
• Configuring Rapid Spanning Tree Settings
• Multiple Spanning Tree
• Defining MSTP Properties
• Mapping VLANs to a MSTP Instance
• Defining MSTP Instance Settings
• Defining MSTP Interface Settings
STP 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 stop transferring user data. After the topology changes so that the
data transfer is made possible, the links are automatically re-activated.
Loops occur when alternate routes exist between hosts. Loops in an extended
network can cause switches to forward traffic indefinitely, resulting in increased
traffic load and reduced network efficiency.
STP provides a tree topology for any arrangement of switches and
interconnecting links, by creating a unique path between end stations on a
network, and thereby eliminating loops.
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