3Com SuperStack 3 3812 Implementation Manual

Contents

Switch Features Explained 19RSTP allows you to implement alternative paths for network traffic in theevent of path failure and uses a loop-detection process to:■ Discover the efficiency of each path.■ Enable the most efficient path.■ Disable the less efficient paths.■ Enable one of the less efficient paths if the most efficient path fails.RSTP is an enhanced version of STP (Spanning Tree Protocol) and is fullycompatible with STP systems. RSTP can restore a network connectionquicker than the legacy STP feature. RSTP can detect if it is connected to alegacy device that only supports IEEE 802.1D STP and will automaticallydowngrade to STP on that particular port.RSTP conforms to the IEEE Std 802.1w-2001.For more information about RSTP, see Chapter 4 “Using ResilienceFeatures”.Switch Database The Switch Database is an integral part of the Switch and is used by theSwitch to determine if a packet should be forwarded, and which portshould transmit the packet if it is to be forwarded.For more information about the Switch Database, see Chapter 5 “Usingthe Switch Database”.Traffic Prioritization The traffic prioritization capabilities of your Switch provides Class ofService (CoS) prioritization to your network. You can prioritize traffic onyour network to ensure that high priority data is transmitted withminimum delay.For more information about traffic prioritization, see Chapter 6 “UsingTraffic Management”.Rate Limiting Rate limiting is the restriction of the bandwidth to or from a section ofyour network. Limiting the rate of network traffic reduces the stress onyour network and, when used with traffic prioritization, ensures thatimportant traffic is not held up when the network is busy.For more information about rate limiting, see Chapter 6 “Using TrafficManagement”.