D-Link DES-5024 manual System Rate Control, Advantages of Store and Forward

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Fast Ethernet Switching System User’s Guide

System Rate Control

The System Rate Control panel, displayed in Figure 23, allows you to set the packet forwarding rate on the DES-5024. There are two options: Store & Forward and Cut- Through.

Figure 23: System Rate Control

The DES-5024 can be set for Store and Forward or Cut-Through. This is a global setting that affects all the ports except the RS-232 port.

Store and Forward means that when the DES-5024 receives an incoming packet it “stores” the packet until the entire data packet has been received before it “forwards” the packet to a destination.

In Cut-Through mode the DES-5024 begins sending out the packet as soon as it receives the first 128 bytes of data. The first 128 bytes contain the destination of the packet.

Advantages of Store and Forward

Store and Forward only sends out valid data packets. Bad packets created by collisions on the network or damaged packets are filtered out.

Always use Store and Forward when some devices on the network run at 10 Mbps and others run at 100 Mbps.

Disadvantages of Store and Forward

Store and Forward requires more time because it receives the whole packet before sending it out. Every byte buffered is an additional eight microseconds of delay. For

Managing the DES-5024

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Contents DES-5024 Fast Ethernet Switching System User’s Guide Link Limited Warranty Hardware North, Central, and South America Copyright Statement Wichtige Sicherheitshinweise Table of Contents Page Page Audience About This GuideOrganization Features IntroductionPage Front Panel DES-5024 Front PanelRear Panel DES-5024 Rear PanelManagement Methods Updating FirmwareLocal Console Management Telnet ManagementInstalling the DES-5024 Unpacking the DES-5024Installation Options Desktop/ Shelf Installation Install Feet on BottomAttach Feet Rack Installation Attach Mounting Brackets Insert into Rack Installing Modules Remove Blank Bracket Insert Optional Module Power On Cable Specifications Connecting the DES-5024 to the NetworkCopper Cable Cable Diagram Fiber Optic Cable Ports MDI-X PortsFiber Optic Ports RS-232 PortConnecting the DES-5024 to other Switches and Hubs DES-5024 to DES-5024 ConnectionLEDs DES-5024 LEDsPower CPU ModuleLED Port 10/100-TX Module LinkPort 100BASE-FX Module ColLit Dark Port 1000BASE-SX Module ActManaging the DES-5024 Local Console Management ∙ Data bits ∙ Parity None ∙ Stop bits ∙ Flow Control NoneTelnet ∙ Default User Name D-Link ∙ Default Password D-Link LogHelp Message Help MessagePanel Conventions SpacebarConsole Program System ConfigurationUser Account Management 100BASE-FX/ 1000BASE-SX Switch Port Module Spanning Tree ConfigurationSnmp Management Configuration Vlan Port ManagementSystem Configuration Menu System ResetFactory Reset to Default Config Values System InformationSoftware Update Boot Prom Firmware VersionSystem Information Menu Hardware RevisionLAN Default Gateway MAC AddressSystem Description System NameSystem Reset System ResetFactory Reset Factory ResetFactory Reset confirmation Advantages of Store and Forward System Rate ControlDisadvantages of Store and Forward Advantages of Cut-Through Disadvantages of Cut-ThroughSoftware Update Menu Software Update menuTransfer Firmware Xmodem User Account Management User Account Change MenuPassword Confirm PasswordAccess Level Create New UserPage Status Delete UsersDelete Page Old Password Change PasswordNew Password Page Switch Port Configuration State Switch Port Configuration MenuPhysical Priority Port StateFlow Control Spanning Tree Configuration Menu Spanning Tree ConfigurationSTA Operation Levels Forward Delay Time Spanning Tree AlgorithmBridge Priority Root CostRoot Bridge Root PortSnmp Management Configuration Snmp Management Configuration Menu Snmp Manager SettingAccess Right Snmp Community StringSnmp Trap Manager Setting Authentication FailureCold Start Link Change EventPage Vlan Port Management Vlan Port Management Menu Vlan Port Management menuCreate New Vlan New Vlan NamePort # TrunkGroupPage Delete Vlan Menu Vlan NameModify Vlan Menu Virtual LAN NameTrunking Port Management Menu Trunking Port Management menuNew Trunking Group Name Create New Trunking PortName Page Trunking Port Delete Trunking PortModify Trunking Port Trunking Port Name Modify Trunking PortTroubleshooting ProblemSolutionPage Diagnostic LED Switch Specifications Appendix a DES-5024 Technical SpecificationsPort Specifications 10BASE-T EMI Fast Ethernet Switching System User’s Guide Performance Access Level IndexUser Name 50, 52