Spanning Tree Concepts A-1
A

Spanning Tree Concepts

A.1 GENERAL
The IEEE 802.1D Spanning Tree Protocol resolves the problems of physical loops in a network by
establishing one primary path between any two switches in a network. Any duplicate paths are
barred from use and become standby or blo cked paths until the original path fails, at which point
they can be brought into service.
A.1.1 Spanning Tree Features
The switch meets the requirements of the Spanning Tree Protocol (STP) by BEING ABLE TO
performing the following functions:
•Create a single spanning tree from any arrangement of switching or bridging elements.
•Compensate automatically for the failure, re moval, or addition of any device in an active data
path.
•Achieve port changes in short time intervals, which establishes a stable active topology quickly
with a minimum of network disturbance.
•Use a minimum amount of communications bandwidth to accomplish the operation of the
Spanning Tree Protocol.
•Reconfigure the active topology in a manner that is transparent to stations transmitting and
receiving data packets.
•Manage the topology in a consistent and reproducible manner through the use of Spanning Tree
Protocol parameters.
NOTE: The term “switch” is used as an equivalent to “bridge” in this document.