What is STP? | Moxa Technologies EDS-508 guide

	EDS-508 Series User’s Manual		Featured Functions
		STP and the protocol features supported by your EDS.

	NOTE	The protocol is part of the IEEE Std 802.1D, 1998 Edition bridge specification. The following
		explanation of STP uses bridge instead of switch.

What is STP?

STP (802.1D) is a bridge-based system that allows you to implement parallel paths for network traffic and uses a loop-detection process to:

#Find and disable the less efficient paths (that is, the paths that have a lower bandwidth).

#Enable one of the less efficient paths if the most efficient path fails.

As an example, the figure below shows a network containing three LAN segments separated by three bridges. With this configuration, each segment uses at most two paths to communicate with the other segments. If STP is NOT enabled, this configuration creates loops that cause the network to overload.

Bridge A

LAN 1

Bridge B

LAN 2

Bridge C

LAN 3

The next figure shows the result of enabling STP on the bridges in the configuration. STP detects duplicate paths and prevents, or blocks, one of them from forwarding traffic, so that the configuration will work satisfactorily. STP could have determined, for example, that traffic from LAN segment 2 to LAN segment 1 should flow through Bridges C and A because this path has a greater bandwidth and is therefore more efficient.

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Moxa Technologies EDS-508 user manual What is STP?

Contents

Second Edition, November Moxa EtherDevice Switch User’s Manual EDS-508 Series Disclaimer Moxa EtherDevice Switch EDS User’s ManualCopyright Notice Trademarks Table of Contents Chapter EDS Configurator GUI Introduction Industrial vs. Commercial Moxa EtherDevice SwitchPackage Checklist Inside the Future of Industrial Ethernet Technology Designed for Industrial Applications FeaturesUseful Utility and Remote Configuration Advanced Industrial Networking CapabilityPage Getting Started Connection Caution Using the RS-232 Serial Console 115200, None, 8, 1, VT100 EDS-508 Series User’s Manual Getting Started Key Function Using the Telnet Console EDS-508 Series User’s Manual Getting Started Using Web Configuration For details Page Featured Functions Switch Description Setting Descriptions Factory Default Configuring Basic SettingsSwitch Name Setting Descriptions Factory Default Switch Location Setting Descriptions Factory Default Account Name PasswordDisable Telnet/Web Console Setting Descriptions Factory Default # Any host can access the NE-4000T Accessible IPPassword Setting # Hosts on the specific subnet can access the NE-4000T Enable/Disable Port PortName Port Transmission Speed Port TypeFDX Flow Control Default Gateway Auto IP ConfigurationSwitch IP Address Switch Subnet Mask Current Time Setting Description Factory Default TimeDNS IP Address Current Date Setting Description Factory Default Time Zone Setting Description Factory DefaultSystem Up Time System File Update-By Remote Tftp Tftp Server IP/Name Setting Description Factory DefaultLog file path and name Setting Description Factory Default Log File Export System File Update-By Local Import/ExportConfiguration File Export Configuration File Import Using Port Trunking Factory DefaultConcept of Port Trunking Configuring Port Trunking Port Trunking SettingsTrunking settings Using Snmp Port setting informationEnable/Disable V1, V2c Read/Write Community Configuring Snmp Snmp Read/Write SettingsSnmp Versions V1, V2c Read Community User Data Encryption Key For Snmp V1, V2c, V3 and V3 only Admin Auth. Type For Snmp V1, V2c, V3 and V3 onlyAdmin Data Encryption Key For Snmp V1, V2c, V3 and V3 only User Auth. Type For Snmp V1, V2c, V3 and V3 only Concept of Turbo Ring Using Communication RedundancyTrap Settings Private MIB information When the number of EDS units in the Turbo Ring is even Page Switch a Coupler Configuring Turbo Ring Concept of STP/RSTP What is STP? STP Requirements How STP Works Port Speed Path Cost 802.1D Edition 802.1w-2001 STP ConfigurationSTP Reconfiguration How Rstp Differs from STP STP Example Using STP on a Network with Multiple VLANs Configuring STP/RSTP Hello time sec Root/Not RootProtocol of Redundancy Bridge priority Port Priority Enable STP per PortConfiguration Limits of RSTP/STP Max. Age sec How Traffic Prioritization Works Using Traffic PrioritizationWhat is Traffic Prioritization? Concept of Traffic Prioritization Differentiated Services DiffServ Traffic Marking Ieee 802.1p Priority Level Ieee 802.1D Traffic TypeTraffic Prioritization Configuring Traffic Prioritization QoS ClassificationTraffic Queues Inspect COS Default Port PriorityQueuing Mechanism Inspect TOS TOS/DiffServ Mapping CoS Mapping Benefits of VLANs Using Virtual LANWhat is a VLAN? Concept of Virtual LAN Vlan VLANs Tagged and Untagged Membership VLANs and Moxa EtherDevice SwitchManagement Vlan Communication Between VLANs Device a Switch a Switch B Sample Applications of VLANs using Moxa EtherDevice Switch Vlan Port Settings Configuring 802.1Q Vlan Port Forbidden Vlan List Management Vlan SettingPort Pvid Port Fixed Vlan List Tagged Vlan Table Using Multicast FilteringWhat is an IP Multicast? Concept of Multicast Filtering Network without multicast filtering Multicast Filtering Enabling Igmp Snooping Configuring Multicast FilteringMulticast Filtering and Moxa EtherDevice Switch Igmp Multicast Filtering Static Multicast Router Port Igmp Snooping Settings Querier intervalIgmp Snooping Enable Global Igmp Snooping Enable per Vlan Add New Static Multicast Address to the List Using Rate LimitingAdd Static Multicast MAC Igmp Table Rate of Normal Priority Queue Configuring Rate LimitingIngress Policy Rate of Low Priority Queue Rate of High Priority Queue Using Port LockAdding a Static Unicast MAC Address Rate of Medium Priority Queue Add Static Unicast MAC Address Using Auto WarningConfiguring Port Lock Configuring Email Warning Event Types Email Alarm Events SettingsConfiguring Email Settings Activate your settings and test email if necessary Email Settings MoxaEtherDeviceSwitch0001@SwitchLocationPort Event Email Address Configuring Relay WarningConfiguring Relay Event Types Mail Server IP/Name Activate your settings Relay Alarm Events Settings Using Line-Swap-Fast-Recovery Relay Alarm ListOverride relay alarm settings Using Set Device IP Configuring Line-Swap Fast RecoveryEnable Line-Swap-Fast-Recovery Set up the connected devices Configuring Set Device IP Output data stream Using DiagnosisMirror Port Desired IP Address Using Monitor Monitor by SwitchPing Monitor by Port ALL Using the MAC Address Table Using Event Log Page EDS Configurator GUI Broadcast Search Starting EDS Configurator Search by IP address Modify IP Address Upgrade Firmware Export Configuration Import Configuration Blank Unlock ServerLocked Unlocked Fixed Locked FixedUnlocked Fixed MIB Groups Page Optical Fiber SpecificationsTechnology Interface Regulatory Approvals PowerMechanical Environment Service Information Following services are provided Moxa Internet Services Problem Report Form Moxa Product % EDS-508Serial Number Product Return Procedure