D-Link DES-3224 manual System Rate Control, Advantages of Store and Forward

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10/100 Auto Negotiation Switch User’s Guide

System Rate Control

The System Rate Control panel, displayed in Figure 14, allows you to set the packet forwarding rate on the DES-3224. There are two options: Store & Forward and Cut-Through.

Figure 14: System Rate Control

The DES-3224 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-3224 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-3224 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 example, 1500

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 Organization About This GuideAudience Front Panel FeaturesIntroduction Side Panels MDI-Uplink port MDI-X portsLocal Console Management Rear PanelManagement Methods Telnet ManagementUpdating Firmware Unpacking the DES-3224 Installing the DES-3224Installation Options Rack Installation Power OnDesktop/ Shelf Installation Connecting the DES-3224 to the Network Cable SpecificationsCable Diagram Cable Requirements MDI-X Port PortsMDI-II Port RS-232 PortConnecting the DES-3224 to the DES-5024 and Hubs DES-3224 to DES-3224 ConnectionPower LED LEDsFull/ Half LED DES-3224 LED PanelSpeed/ Link/ Activity LED Utilization LEDs Managing the DES-3224 Local Console ManagementTelnet ∙ Parity None ∙ Stop bits ∙ Flow Control None∙ Default User Name D-Link ∙ Default Password D-Link LogHelp Message Help MessageSpacebar Spanning Tree Configuration System ConfigurationSwitch Port 1-8, 9-16, 17-24 Configuration Console ProgramVlan Port Management System Configuration MenuSnmp Management Configuration Trunking Port ManagementSoftware Update System ResetFactory Reset to Default Config Values System InformationHardware Revision Boot Prom Firmware VersionSystem Information Menu Software VersionSystem Name LAN Default GatewaySystem Description System LocationSystem Reset System ResetFactory Reset Factory ResetFactory Reset Confirmation Disadvantages of Store and Forward System Rate ControlAdvantages of Store and Forward Advantages of Cut-Through Disadvantages of Cut-ThroughSoftware Update Menu Software UpdateSoftware Update Transfer Message Displayed as Eeprom is Being Written Create New User User Account ManagementUser Account Change Menu Access Level PasswordConfirm Password User NameDelete Users StatusDelete New Password Change PasswordOld Password State Switch Port ConfigurationSwitch Port Configuration Menu Priority PhysicalPort State STA Operation Levels Spanning Tree ConfigurationSpanning Tree Configuration Menu Bridge Priority Forward Delay TimeSpanning Tree Algorithm Root CostRoot Bridge Root PortSnmp Management Configuration Snmp Management Configuration MenuSnmp Community String Snmp Manager SettingAccess Right Cold Start Snmp Trap Manager SettingAuthentication Failure Link Change EventPage Vlan Port Management Vlan Port Management MenuVlan Port Management menu Port # Create/ View VlanNew Vlan Name TrunkGroupDelete Vlan Menu Vlan NameModify Vlan Menu Virtual LAN NameVlan Modify menu Trunking Port Management Menu Trunking Port Management menuName Create New Trunking PortNew Trunking Group Name Delete Trunking Port Trunking PortModify Trunking Port Trunking Port NameTrunking Port Modify menu Troubleshooting Problem SolutionPower LED is Off System Error LED Indicators Port Specifications DES-3224 Technical SpecificationsSwitch Specifications General EMI Access Level IndexUser Name 34, 35