GS1510 Series User’s Guide
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CHAPTER 17
Spanning Tree Protocol
17.1 Overview
(R)STP detects and breaks network loops and provides backup links between
switches, bridges or routers. It allows a Switch to interact with other (R)STP-
compliant switches in your network to ensure that only one path exists between
any two stations on the network.
The Switch supports Spanning Tree Protocol (STP) and Rapid Spanning Tree
Protocol (RSTP) as defined in the following standards.
• IEEE 802.1D Spanning Tree Protocol
• IEEE 802.1w Rapid Spanning Tree Protocol
17.2 What You Can DO
•Use the General Settings screen (Section 17.4 on page 97) to enable and
configure STP.
•Use the STP Status screen (Section 17.5 on page 98) to check the STP current
status.
17.3 What You Need to Know
The Switch uses IEEE 802.1w RSTP (Rapid Spanning Tree Protocol) that allows
faster convergence of the spanning tree than STP (while also being backwards
compatible with STP-only aware bridges). In RSTP, topology change information is
directly propagated throughout the network from the device that generates the
topology change. In STP, a longer delay is required as the device that causes a
topology change first notifies the root bridge and then the root bridge notifies the
network. Both RSTP and STP flush unwanted learned addresses from the filtering
database. In RSTP, the port states are Discarding, Learning, and Forwarding.
Note: In this user’s guide, “STP” refers to both STP and RSTP.
