D-Link DES-3224 Spanning Tree Algorithm, Bridge Priority, Root Cost, Hello Time, Max Age Time

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10/100 Auto Negotiation Switch User’s Guide

Spanning Tree Algorithm

Spanning Tree Algorithm can be enabled or disabled. Use Spanning Tree to prevent network loops.

Bridge Priority

The Bridge Priority can be from 0 to 65535. Zero is the highest Bridge Priority. The higher the Bridge Priority the greater the chance that the DES-3224 will be selected as the Root Bridge. The DES-3224 with the highest Bridge Priority is the Root Bridge.

Root Cost

The Root Cost is the number of times a packet is regenerated before reaching its destination. A source sends a packet to the first device (switch or hub) on the network. When the packet reaches the next hub or switch and it is sent out again, the Path Cost becomes two. Each switch and active hub regenerates the packet. To determine the Root Path Cost, count the number of times the packet is regenerated.

The switch with the lowest Path Cost is the Root Bridge. Make the Root Bridge the best switch on the network.

Hello Time

Is the interval between two transmissions of packets sent by the Root Bridge to tell all other switches that it is the Root Bridge. The Hello Time can be set manually, with a range in seconds from 1 to 10. If the Hello Time is set for the switch and the switch is not the Root Bridge then the Hello Time will not take effect until the switch becomes the Root Bridge.

Forward Delay Time

This is the time any port on the DES-3224 spends in the listening state while moving from the listening state to the forwarding state. It can be set from 4 to 30 seconds.

Use the following formula when setting the Hello Time and the Forward Delay Time:

2 x (Forward Delay minus 1 second) > Max Age

2 x (Hello Time plus 1 second) < Max Age

Max Age Time

Is the time a non-root bridge waits for a packet to be sent. At the end of the Max Age, if a packet has not been received from the Root Bridge, the DES-3224 will start sending its own packets and request permission to become the Root Bridge. If it turns out that the DES-3224 has the lowest Bridge Identifier it will become the Root Bridge.

The switch with the lowest Bridge Identifier is the Root Bridge. It is best to make the Root Bridge the best switch on the network to ensure the best network performance and reliability.

Managing the DES-3224

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Contents DES-3224 10/100 Auto Negotiation Switch User’s Guide Link Limited Warranty Hardware North, Central, and South America FCC Warning Wichtige Sicherheitshinweise Page Table of Contents Page Page Page About This Guide AudienceOrganization Features IntroductionFront Panel MDI-Uplink port MDI-X ports Side PanelsTelnet Management Rear PanelManagement Methods Local Console ManagementUpdating Firmware Installing the DES-3224 Installation OptionsUnpacking the DES-3224 Power On Desktop/ Shelf InstallationRack Installation Cable Specifications Connecting the DES-3224 to the NetworkCable Diagram Cable Requirements RS-232 Port PortsMDI-II Port MDI-X PortDES-3224 to DES-3224 Connection Connecting the DES-3224 to the DES-5024 and HubsLEDs Power LEDDES-3224 LED Panel Speed/ Link/ Activity LEDFull/ Half LED Utilization LEDs Local Console Management Managing the DES-3224∙ Parity None ∙ Stop bits ∙ Flow Control None TelnetLog ∙ Default User Name D-Link ∙ Default Password D-LinkHelp Message Help MessageSpacebar Console Program System ConfigurationSwitch Port 1-8, 9-16, 17-24 Configuration Spanning Tree ConfigurationTrunking Port Management System Configuration MenuSnmp Management Configuration Vlan Port ManagementSystem Information System ResetFactory Reset to Default Config Values Software UpdateSoftware Version Boot Prom Firmware VersionSystem Information Menu Hardware RevisionSystem Location LAN Default GatewaySystem Description System NameSystem Reset System ResetFactory Reset Factory ResetFactory Reset Confirmation System Rate Control Advantages of Store and ForwardDisadvantages of Store and Forward Disadvantages of Cut-Through Advantages of Cut-ThroughSoftware Update Software Update MenuSoftware Update Transfer Message Displayed as Eeprom is Being Written User Account Management User Account Change MenuCreate New User User Name PasswordConfirm Password Access LevelStatus Delete UsersDelete Change Password Old PasswordNew Password Switch Port Configuration Switch Port Configuration MenuState Physical Port StatePriority Spanning Tree Configuration Spanning Tree Configuration MenuSTA Operation Levels Root Cost Forward Delay TimeSpanning Tree Algorithm Bridge PriorityRoot Port Root BridgeSnmp Management Configuration Menu Snmp Management ConfigurationSnmp Manager Setting Access RightSnmp Community String Link Change Event Snmp Trap Manager SettingAuthentication Failure Cold StartPage Vlan Port Management Menu Vlan Port ManagementVlan Port Management menu TrunkGroup Create/ View VlanNew Vlan Name Port #Vlan Name Delete Vlan MenuVirtual LAN Name Modify Vlan MenuVlan Modify menu Trunking Port Management menu Trunking Port Management MenuCreate New Trunking Port New Trunking Group NameName Trunking Port Delete Trunking PortTrunking Port Name Modify Trunking PortTrunking Port Modify menu Problem Solution TroubleshootingPower LED is Off System Error LED Indicators DES-3224 Technical Specifications Switch SpecificationsPort Specifications General EMI Index Access LevelUser Name 34, 35