Moxa Technologies PT-7728 Differences between Rstp and STP, STP Example, STP Reconfiguration

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PT-7728 User’s Manual

Featured Functions

STP Reconfiguration

Once the network topology has stabilized, each bridge listens for "Hello" BPDUs that are transmitted from the Root Bridge at regular intervals. If a bridge does not receive a "Hello" BPDU after a certain interval (the Max Age time), the bridge assumes that the Root Bridge, or a link between itself and the Root Bridge, has gone down. This will trigger the bridge to reconfigure the network to account for the change. If you have configured an SNMP trap destination, the first bridge to detect a topology change in your network sends out an SNMP trap.

Differences between RSTP and STP

RSTP is similar to STP, but includes additional information in the BPDUs that allow each bridge to confirm that it has taken action to prevent loops from forming when it decides to enable a link to a neighboring bridge. Adjacent bridges connected via point-to-point links will be able to enable a link without waiting to ensure that all other bridges in the network have had time to react to the change. The main benefit of RSTP is that the configuration decision is made locally rather than network-wide, allowing RSTP can carry out automatic configuration and restore a link faster than STP.

STP Example

The LAN shown below has three segments, with adjacent segments connected using two possible links. The various STP factors, such as Cost, Root Port, Designated Bridge Port, and Blocked Port are shown in the figure.

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Contents Moxa PowerTrans Switch PT-7728 User’s Manual First Edition, February Moxa IncDisclaimer Copyright NoticeTrademarks Table of Contents Appendix a MIB Groups Appendix B Specifications ‰ Overview ‰ Package Checklist ‰ Software Features IntroductionOverview Package ChecklistSoftware Features Getting Started Serial Console Configuration 115200, None, 8, 1, VT100 PT-7728 User’s Manual Getting Started Configuration by Telnet Console Key FunctionPT-7728 User’s Manual Getting Started PT-7728 User’s Manual Getting Started Configuration by Web Browser Disabling Telnet and Browser Access Featured Functions Configuring Basic Settings System IdentificationAccount PasswordPassword Accessible IP Grant access to one host with a specific IP addressGrant access to any host on a specific subnetwork Hosts That Need Access Input FormatEnable PortDescription NameFDX Flow Ctrl NetworkSpeed Auto IP Configuration Switch IP AddressSwitch Subnet Mask Default GatewayTime Daylight Saving TimeCurrent Time Current DateSystem File Update-By Remote Tftp Configuration Files Path and Name Tftp Server IP/NameFirmware Files Path and Name Log Files Path and NameSystem File Update-By Local Import/Export Factory DefaultUsing Port Trunking Port Trunking ConceptConfiguring Port Trunking Trunk Group Maximum of 4 trunk groupsTrunk Type Available Ports/Member PortsTrunk Table Configuring SnmpSetting Description Snmp Read/Write Settings Snmp VersionsV1, V2c Read Community V1, V2c Write/Read CommunitySetting Description Factory Default 1st Trap Server IP/Name Setting Description Factory DefaultUsing Communication Redundancy Private MIB informationInitial setup for Turbo Ring or Turbo Ring Turbo Ring ConceptTurbo Ring with odd number switches Ring Coupling Configuration Determining the Redundant Path for Turbo RingSwitch B Configuring Turbo Ring Configuring Turbo Ring and Turbo RingDual-Homing Configuration for Turbo Ring Now Active Master/SlaveRedundancy Protocol Set as MasterCoupling Control Port Enable Ring CouplingCoupling Port Enable Ring Ring 1/2-StatusRing 1/2-1st Ring Port Status Ring 1/2-2nd Ring Port Status Coupling-ModeCoupling Mode Primary/Backup PortWhat is STP? STP/RSTP ConceptPT-7728 User’s Manual Featured Functions STP Configuration How STP WorksSTP Requirements Port Speed Path Cost 802.1D Edition 802.1w-2001STP Example STP ReconfigurationDifferences between Rstp and STP Using STP on a Network with Multiple VLANs Configuring STP/RSTP Root/Not RootProtocol of Redundancy Bridge PriorityForwarding Delay Enable STP per PortHello Time sec Max. Age secUsing Traffic Prioritization Configuration Limits of RSTP/STPWhat is Traffic Prioritization? Traffic Prioritization ConceptHow Traffic Prioritization Works Ieee 802.1p Priority Level Ieee 802.1D Traffic TypeTraffic Queues Differentiated Services DiffServ Traffic MarkingTraffic Prioritization Configuring Traffic Prioritization QoS ClassificationQueuing Mechanism Inspect TOSSetting Description Factory CoS MappingTOS/DiffServ Mapping Inspect COSVirtual LAN Vlan Concept Using Virtual LANWhat is a VLAN? VLANs and the PowerTrans Benefits of VLANsManaging a Vlan Communication Between VLANsSample Applications of VLANs using PT-7728 VLANs Tagged and Untagged MembershipPT-7728 User’s Manual Featured Functions Configuring Virtual LAN Vlan SettingsManagement Vlan ID Port TypeUsing Multicast Filtering What is an IP Multicast?Concept of Multicast Filtering Vlan TableNetwork without multicast filtering Benefits of MulticastMulticast Filtering Multicast Filtering and Moxa PowerTrans Switch Igmp Internet Group Management Protocol Snooping ModeQuery Mode Network with multicast filteringConfiguring Igmp Snooping Igmp Multicast FilteringGmrp Garp Multicast Registration Protocol Static Multicast MACIgmp Snooping Settings Add Static Multicast MAC Using Bandwidth Management Configuring GmrpGmrp enable Gmrp TableIngress Configuring Bandwidth Management Broadcast Storm ProtectionTraffic Rate Limiting Settings Using Port Access Control Configuring Static Port LockStatic Port Lock IeeeConfiguring Ieee Database OptionRadius Server Server Port802.1X Re-Authentication Local User Database SetupLocal User Database Setup Using Auto WarningPort Access Control Table Configuring Email Warning Event TypeEmail Setup MoxaPowerTransSwitch0001@SwitchLocationPort Events Mail Server IP/NameConfiguring Relay Warning Password SettingAccount Name Email AddressEvent Setup Using Line-Swap-Fast-Recovery Using Set Device IPConfiguring Line-Swap Fast Recovery Override relay alarm settingsConfiguring Set Device IP Set up the connected devicesUsing Diagnosis Mirror PortPing Using MonitorMonitor by Switch Using the MAC Address Table Monitor by PortUsing Event Log MACUsing Syslog Syslog ServerPT-7728 User’s Manual Featured Functions MIB II.1 System Group MIB II.2 Interfaces GroupMIB II.4 IP Group MIB II.5 Icmp GroupMIB II.17 dot1dBridge Group MIB II.10 Transmission GroupMIB II.11 Snmp Group Public Traps Private TrapsInterface Switch PropertiesTechnology Power Optical Fiber 100BaseFXEnvironmental WarrantyMechanical