D-Link DES-3550 User manual

D-Link ™ DES-3550
Managed 48-port 10/100Mbps and 2GE ports Layer 2
Ethernet Switch
Release II
Manual
Second Edition (June 2004)
Printed In Taiwan
RECYCLABLE

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Information in this document is subject to change without notice.
© 2004 D-Link Computer Corporation. All rights reserved.
Reproduction in any manner whatsoever without the written permission of D-Link Computer Corporation is strictly forbidden.
Trademarks used in this text: D-Link and the D-LINK logo are trademarks of D-Link Computer Corporation; Microsoft and Windows are registered
trademarks of Microsoft Corporation.
Other trademarks and trade names may be used in this document to refer to either the entities claiming the marks and names or their products. D-Link
Computer Corporation disclaims any proprietary interest in trademarks and trade names other than its own.
June 2004 P/N 651ES3550025

DES-3550 Fast Ethernet Layer 2 Switch
Table of Contents
Preface............................................................................................................................................................................. viii
Intended Readers ................................................................................................................................................................ix
Typographical Conventions.............................................................................................................................................................. ix
Notes, Notices, and Cautions..............................................................................................................................................ix
Safety Instructions...............................................................................................................................................................x
Safety Cautions.................................................................................................................................................................................. x
General Precautions for Rack-Mountable Products .......................................................................................................................... xi
Protecting Against Electrostatic Discharge...................................................................................................................................... xii
Introduction..............................................................................................................................................................................1
Fast Ethernet...................................................................................................................................................................................... 1
Gigabit Ethernet Technology............................................................................................................................................................. 1
Switching Technology ....................................................................................................................................................................... 2
Switch Description............................................................................................................................................................................. 2
Features.............................................................................................................................................................................................. 2
Ports................................................................................................................................................................................................... 3
Front-Panel Components ................................................................................................................................................................... 4
LED Indicators .................................................................................................................................................................................. 4
Rear Panel Description ...................................................................................................................................................................... 5
Side Panel Description....................................................................................................................................................................... 5
Gigabit Combo Ports ......................................................................................................................................................................... 6
Installation................................................................................................................................................................................7
Package Contents............................................................................................................................................................................... 7
Before You Connect to the Network.................................................................................................................................................. 8
Installing the Switch Without the Rack ............................................................................................................................................. 8
Installing the Switch in a Rack .......................................................................................................................................................... 9
Mounting the Switch in a Standard 19" Rack.................................................................................................................................... 9
Power On .................................................................................................................................................................10
Power Failure...........................................................................................................................................................10
Connecting The Switch ..........................................................................................................................................................10
Switch To End Node........................................................................................................................................................................ 10
Switch to Hub or Switch.................................................................................................................................................................. 11
Connecting To Network Backbone or Server .................................................................................................................................. 11
Introduction To Switch Management.....................................................................................................................................12
Management Options ........................................................................................................................................................13
Web-based Management Interface................................................................................................................................................... 13
SNMP-Based Management.............................................................................................................................................................. 13
Command Line Console Interface Through The Serial Port............................................................................................................ 13
Connecting the Console Port (RS-232 DCE)...........................................................................................................13
First Time Connecting to The Switch.............................................................................................................................................. 14
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Password Protection......................................................................................................................................................................... 16
SNMP Settings ................................................................................................................................................................................ 16
Traps ........................................................................................................................................................................17
MIBs ........................................................................................................................................................................17
IP Address Assignment.................................................................................................................................................................... 17
Connecting Devices to the Switch ................................................................................................................................................... 19
Introduction to Web-based Switch Configuration..................................................................................................................20
Introduction .......................................................................................................................................................................20
Login to Web Manager.................................................................................................................................................................... 20
Web-based User Interface................................................................................................................................................................ 21
Areas of the User Interface ......................................................................................................................................21
Web Pages ....................................................................................................................................................................................... 22
Configuring The Switch.........................................................................................................................................................23
Switch Information............................................................................................................................................................23
IP Address .........................................................................................................................................................................24
Setting the Switch's IP Address using the Console Interface...................................................................................26
Advanced Settings.............................................................................................................................................................26
Port Configurations ...........................................................................................................................................................28
Port Description.................................................................................................................................................................30
Port Mirroring ...................................................................................................................................................................32
Link Aggregation ..............................................................................................................................................................33
Understanding Port Trunk Groups...........................................................................................................................33
LACP Port Setting.............................................................................................................................................................35
MAC Notification..............................................................................................................................................................37
MAC Notification Global Settings ..........................................................................................................................37
MAC Notification Port Settings...............................................................................................................................37
IGMP.................................................................................................................................................................................39
IGMP Snooping .......................................................................................................................................................39
Static Router Ports ...................................................................................................................................................41
Spanning Tree ...................................................................................................................................................................42
802.1s MSTP ...........................................................................................................................................................42
802.1w Rapid Spanning Tree...................................................................................................................................43
Port Transition States...............................................................................................................................................43
Edge Port .................................................................................................................................................................44
P2P Port ...................................................................................................................................................................44
802.1d / 802.1w / 802.1s Compatibility...................................................................................................................44
STP Bridge Global Settings............................................................................................................................................................. 44
MST Configuration Table................................................................................................................................................................ 47
MSTI Settings.................................................................................................................................................................................. 50
STP Instance Settings ...................................................................................................................................................................... 51
MSTP Port Information ................................................................................................................................................................... 51
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Forwarding Filtering..........................................................................................................................................................54
Unicast Forwarding ......................................................................................................................................................................... 54
Static Multicast Forwarding............................................................................................................................................................. 54
Multicast Port Filtering.................................................................................................................................................................... 56
VLANs ..............................................................................................................................................................................57
Understanding IEEE 802.1p Priority ............................................................................................................................................... 57
VLAN Description........................................................................................................................................................................... 57
Notes About VLANs on the DES-3550...................................................................................................................58
IEEE 802.1Q VLANs ...................................................................................................................................................................... 58
802.1Q VLAN Tags.................................................................................................................................................59
Port VLAN ID .........................................................................................................................................................60
Tagging and Untagging............................................................................................................................................60
Ingress Filtering .......................................................................................................................................................61
Default VLANs........................................................................................................................................................61
Port-based VLANs...................................................................................................................................................61
VLAN Segmentation ...............................................................................................................................................62
VLAN and Trunk Groups ........................................................................................................................................62
Static VLAN Entry .......................................................................................................................................................................... 62
GVRP Setting .................................................................................................................................................................................. 64
Traffic Control................................................................................................................................................................................. 66
Port Security......................................................................................................................................................................67
QoS....................................................................................................................................................................................69
The Advantages of QoS................................................................................................................................................................... 69
Understanding QoS.......................................................................................................................................................................... 70
Port Bandwidth................................................................................................................................................................................ 71
Scheduling ....................................................................................................................................................................................... 73
802.1p Default Priority .................................................................................................................................................................... 74
802.1p User Priority......................................................................................................................................................................... 76
Traffic Segmentation ....................................................................................................................................................................... 76
System Log Server........................................................................................................................................................................... 78
SNTP Settings.................................................................................................................................................................................. 80
Current Time Settings..............................................................................................................................................80
Time Zone and DST ................................................................................................................................................81
Access Profile Table..........................................................................................................................................................83
Configuring the Access Profile Table.............................................................................................................................................. 83
PAE Access Entity (802.1X).............................................................................................................................................96
802.1x Port-Based and MAC-Based Access Control....................................................................................................................... 96
Authentication Server ..............................................................................................................................................97
Authenticator ...........................................................................................................................................................98
Client........................................................................................................................................................................99
Authentication Process .................................................................................................................................................................... 99
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Port-Based Network Access Control ............................................................................................................................................... 99
MAC-Based Network Access Control ........................................................................................................................................... 101
Configure Authenticator ................................................................................................................................................................ 101
PAE System Control...................................................................................................................................................................... 104
Port Capability .......................................................................................................................................................104
Initializing Ports for Port Based 802.1x.................................................................................................................106
Initializing Ports for MAC Based 802.1x ..............................................................................................................108
Reauthenticate Port(s) for Port Based 802.1x ........................................................................................................108
RADIUS Server............................................................................................................................................................................. 109
Layer 3 IP Networking ....................................................................................................................................................111
Static ARP Table ........................................................................................................................................................................... 111
Management.........................................................................................................................................................................113
Security IP .......................................................................................................................................................................113
User Accounts .................................................................................................................................................................113
Admin and User Privileges ....................................................................................................................................114
Access Authentication Control........................................................................................................................................115
Policy & Parameters ...................................................................................................................................................................... 116
Application's Authentication Settings............................................................................................................................................ 116
Authentication Server Group Settings ........................................................................................................................................... 117
Authentication Server Hosts .......................................................................................................................................................... 118
Login Method Lists........................................................................................................................................................................ 120
Enable Method Lists ...................................................................................................................................................................... 122
Local Enable Password.................................................................................................................................................................. 123
Enable Admin................................................................................................................................................................................ 124
Secure Socket Layer (SSL) .............................................................................................................................................125
Download Certificate..................................................................................................................................................................... 125
Ciphersuite..................................................................................................................................................................................... 126
Secure Shell (SSH)..........................................................................................................................................................127
SSH Configuration......................................................................................................................................................................... 128
SSH Algorithm .............................................................................................................................................................................. 129
SSH User Authentication............................................................................................................................................................... 131
SNMP Manager...............................................................................................................................................................133
SNMP Settings .............................................................................................................................................................................. 133
Traps ......................................................................................................................................................................133
MIBs ......................................................................................................................................................................133
SNMP User Table.......................................................................................................................................................................... 134
SNMP View Table......................................................................................................................................................................... 136
SNMP Group Table ....................................................................................................................................................................... 137
SNMP Community Table Configuration ....................................................................................................................................... 139
SNMP Host Table.......................................................................................................................................................................... 140
SNMP Engine ID........................................................................................................................................................................... 141
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Monitoring ...........................................................................................................................................................................142
Port Utilization ................................................................................................................................................................142
CPU Utilization ...............................................................................................................................................................143
Packets.............................................................................................................................................................................144
Received(RX) ................................................................................................................................................................................ 144
UMB Cast(RX).............................................................................................................................................................................. 146
Transmitted (TX)........................................................................................................................................................................... 148
Errors...............................................................................................................................................................................150
Received (RX) ............................................................................................................................................................................... 151
Transmitted (TX)........................................................................................................................................................................... 153
Size..................................................................................................................................................................................155
MAC Address..................................................................................................................................................................157
Switch History.................................................................................................................................................................159
IGMP Snooping Group ...................................................................................................................................................160
IGMP Snooping Forwarding ...........................................................................................................................................161
VLAN Status ...................................................................................................................................................................161
Router Port ......................................................................................................................................................................162
Port Access Control.........................................................................................................................................................163
Authenticator State ................................................................................................................................................163
Layer 3 Feature................................................................................................................................................................165
Browse ARP Table ........................................................................................................................................................................ 165
Maintenance .........................................................................................................................................................................166
TFTP Services .................................................................................................................................................................166
Download Firmware From TFTP Server ....................................................................................................................................... 166
Download Configuration File ........................................................................................................................................................ 168
Upload Configuration .................................................................................................................................................................... 168
Upload Log.................................................................................................................................................................................... 168
Ping Test..........................................................................................................................................................................169
Save Changes ..................................................................................................................................................................169
Reset................................................................................................................................................................................170
Reset System ...................................................................................................................................................................170
Reset Config....................................................................................................................................................................171
Reboot Device .................................................................................................................................................................171
Logout .............................................................................................................................................................................171
D-Link Single IP Management ............................................................................................................................................173
Single IP Management (SIM) Overview .........................................................................................................................173
SIM Using The Web Interface ........................................................................................................................................174
Topology .........................................................................................................................................................................175
Tool Tips .........................................................................................................................................................................178
Right Click..................................................................................................................................................................................... 180
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Group Icon .............................................................................................................................................................180
Commander Switch Icon........................................................................................................................................181
Member Switch Icon..............................................................................................................................................182
Candidate Switch Icon ...........................................................................................................................................183
Menu Bar....................................................................................................................................................................................... 184
Group .....................................................................................................................................................................185
Device....................................................................................................................................................................185
View.......................................................................................................................................................................185
Firmware Upgrade...........................................................................................................................................................185
Configuration File Backup/Restore.................................................................................................................................186
Appendix A ..........................................................................................................................................................................187
Appendix B ..........................................................................................................................................................................189
Cables and Connectors...........................................................................................................................................189
Appendix C ..........................................................................................................................................................................190
Cable Lengths ........................................................................................................................................................190
Glossary ...............................................................................................................................................................................191
Warranty and Registration Information ...............................................................................................................................198
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Preface
The DES-3550 Manual is divided into sections that describe the system installation and operating instructions with
examples.
Section 1, “Introduction”– Describes the Switch and its features.
Section 2, “Installation” – Helps you get started with the basic installation of the Switch and also describes the front panel,
rear panel, side panels, and LED indicators of the Switch.
Section 3, “Connecting the Switch” – Tells how you can connect the Switch to your Ethernet/Fast Ethernet network.
Section 4, “Introduction to Switch Management” – Introduces basic Switch management features, including password
protection, SNMP settings, IP address assignment and connecting devices to the Switch.
Section 5, “Introduction to Web-based Switch Management” – Talks about connecting to and using the Web-based switch
management feature on the Switch.
Section 6, “Configuring the Switch” – A detailed discussion about configuring some of the basic functions of the Switch,
including accessing the Switch information, using the Switch's utilities and setting up network configurations, such as
Quality of Service, The Access Profile Table, port mirroring and configuring the Spanning Tree.
Section 7, “Management” – A discussion of the security features of the Switch, including Security IP, User Accounts,
Access Authentication Control, and SNMP.
Section 8, “Monitoring” – Features graphs and screens used in monitoring features and packets on the Switch.
Section 9, “Maintenance” – Features information on Switch utility functions, including TFTP Services, Switch History,
Ping Test Save Changes and Rebooting Services.
Section 10, “Single IP Management” – Discussion on the Single IP Management function of the Switch, including
functions and features of the Java based user interface and the utilities of the SIM function.
Appendix A, “Technical Specifications” – The technical specifications of the DES-3550
Appendix B, “Cables and Connectors” – Describes the RJ-45 receptacle/connector, straight-through and crossover cables
and standard pin assignments.
Appendix C, “Cable Lengths” – Information on cable types and maximum distances.
Glossary - Lists definitions for terms and acronyms used in this document.
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DES-3550 Fast Ethernet Layer 2 Switch
Intended Readers
The DES-3550 Manual contains information for setup and management of the Switch. This manual is intended for
network managers familiar with network management concepts and terminology.
Typographical Conventions
Convention Description
[ ] In a command line, square brackets indicate an optional entry. For example: [copy
filename] means that optionally you can type copy followed by the name of the file.
Do not type the brackets.
Bold font Indicates a button, a toolbar icon, menu, or menu item. For example: Open the File
menu and choose Cancel. Used for emphasis. May also indicate system messages
or prompts appearing on your screen. For example: You have mail. Bold font is also
used to represent filenames, program names and commands. For example: use the
copy command.
Boldface
Typewriter Font Indicates commands and responses to prompts that must be typed exactly as printed
in the manual.
Initial capital letter Indicates a window name. Names of keys on the keyboard have initial capitals. For
example: Click Enter.
Italics Indicates a window name or a field. Also can indicate a variables or parameter that is
replaced with an appropriate word or string. For example: type filename means that
you should type the actual filename instead of the word shown in italic.
Menu Name > Menu
Option
Menu Name > Menu Option Indicates the menu structure. Device > Port > Port
Properties means the Port Properties menu option under the Port menu option that
is located under the Device menu.
Notes, Notices, and Cautions
A NOTE indicates important information that helps you make better use of
your device.
A NOTICE indicates either potential damage to hardware or loss of data
and tells you how to avoid the problem.
A CAUTION indicates a potential for property damage, personal injury, or
death.
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DES-3550 Fast Ethernet Layer 2 Switch
Safety Instructions
Use the following safety guidelines to ensure your own personal safety and to help protect your system from potential
damage. Throughout this safety section, the caution icon ( ) is used to indicate cautions and precautions that you
need to review and follow.
Safety Cautions
To reduce the risk of bodily injury, electrical shock, fire, and damage to the equipment, observe the following precautions.
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Observe and follow service markings.
Do not service any product except as explained in your system documentation.
Opening or removing covers that are marked with the triangular symbol with a lightning bolt may expose you to
electrical shock.
Only a trained service technician should service components inside these compartments.
If any of the following conditions occur, unplug the product from the electrical outlet and replace the part or contact
your trained service provider:
The power cable, extension cable, or plug is damaged.
An object has fallen into the product.
The product has been exposed to water.
The product has been dropped or damaged.
The product does not operate correctly when you follow the operating instructions.
Keep your system away from radiators and heat sources. Also, do not block cooling vents.
Do not spill food or liquids on your system components, and never operate the product in a wet environment. If the
system gets wet, see the appropriate section in your troubleshooting guide or contact your trained service provider.
Do not push any objects into the openings of your system. Doing so can cause fire or electric shock by shorting out
interior components.
Use the product only with approved equipment.
Allow the product to cool before removing covers or touching internal components.
Operate the product only from the type of external power source indicated on the electrical ratings label. If you are
not sure of the type of power source required, consult your service provider or local power company.
To help avoid damaging your system, be sure the voltage selection switch (if provided) on the power supply is set to
match the power available at your location:
115 volts (V)/60 hertz (Hz) in most of North and South America and some Far Eastern countries such as South
Korea and Taiwan
100 V/50 Hz in eastern Japan and 100 V/60 Hz in western Japan
230 V/50 Hz in most of Europe, the Middle East, and the Far East
Also be sure that attached devices are electrically rated to operate with the power available in your location.
Use only approved power cable(s). If you have not been provided with a power cable for your system or for any AC-
powered option intended for your system, purchase a power cable that is approved for use in your country. The power
cable must be rated for the product and for the voltage and current marked on the product's electrical ratings label.
The voltage and current rating of the cable should be greater than the ratings marked on the product.
To help prevent electric shock, plug the system and peripheral power cables into properly grounded electrical outlets.
These cables are equipped with three-prong plugs to help ensure proper grounding. Do not use adapter plugs or
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DES-3550 Fast Ethernet Layer 2 Switch
remove the grounding prong from a cable. If you must use an extension cable, use a 3-wire cable with properly
grounded plugs.
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Observe extension cable and power strip ratings. Make sure that the total ampere rating of all products plugged into
the extension cable or power strip does not exceed 80 percent of the ampere ratings limit for the extension cable or
power strip.
To help protect your system from sudden, transient increases and decreases in electrical power, use a surge
suppressor, line conditioner, or uninterruptible power supply (UPS).
Position system cables and power cables carefully; route cables so that they cannot be stepped on or tripped over. Be
sure that nothing rests on any cables.
Do not modify power cables or plugs. Consult a licensed electrician or your power company for site modifications.
Always follow your local/national wiring rules.
When connecting or disconnecting power to hot-pluggable power supplies, if offered with your system, observe the
following guidelines:
Install the power supply before connecting the power cable to the power supply.
Unplug the power cable before removing the power supply.
If the system has multiple sources of power, disconnect power from the system by unplugging all power cables
from the power supplies.
Move products with care; ensure that all casters and/or stabilizers are firmly connected to the system. Avoid sudden
stops and uneven surfaces.
General Precautions for Rack-Mountable
Products
Observe the following precautions for rack stability and safety. Also refer to the rack installation documentation
accompanying the system and the rack for specific caution statements and procedures.
Systems are considered to be components in a rack. Thus, "component" refers to any system as well as to various
peripherals or supporting hardware.
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CAUTION: Installing systems in a rack without the front and side
stabilizers installed could cause the rack to tip over, potentially resulting in
bodily injury under certain circumstances. Therefore, always install the
stabilizers before installing components in the rack. After installing
system/components in a rack, never pull more than one component out of
the rack on its slide assemblies at one time. The weight of more than one
extended component could cause the rack to tip over and may result in
serious injury.
Before working on the rack, make sure that the stabilizers are secured to the rack, extended to the floor, and that the
full weight of the rack rests on the floor. Install front and side stabilizers on a single rack or front stabilizers for joined
multiple racks before working on the rack.
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Always load the rack from the bottom up, and load the heaviest item in the rack first.
Make sure that the rack is level and stable before extending a component from the rack.
Use caution when pressing the component rail release latches and sliding a component into or out of a rack; the slide
rails can pinch your fingers.
After a component is inserted into the rack, carefully extend the rail into a locking position, and then slide the
component into the rack.
Do not overload the AC supply branch circuit that provides power to the rack. The total rack load should not exceed
80 percent of the branch circuit rating.
Ensure that proper airflow is provided to components in the rack.
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DES-3550 Fast Ethernet Layer 2 Switch
Do not step on or stand on any component when servicing other components in a rack.•
NOTE: A qualified electrician must perform all connections to DC power
and to safety grounds. All electrical wiring must comply with applicable
local or national codes and practices.
CAUTION: Never defeat the ground conductor or operate the equipment
in the absence of a suitably installed ground conductor. Contact the
appropriate electrical inspection authority or an electrician if you are
uncertain that suitable grounding is available.
CAUTION: The system chassis must be positively grounded to the rack
cabinet frame. Do not attempt to connect power to the system until
grounding cables are connected. Completed power and safety ground
wiring must be inspected by a qualified electrical inspector. An energy
hazard will exist if the safety ground cable is omitted or disconnected.
Protecting Against Electrostatic Discharge
Static electricity can harm delicate components inside your system. To prevent static damage, discharge static electricity
from your body before you touch any of the electronic components, such as the microprocessor. You can do so by
periodically touching an unpainted metal surface on the chassis.
You can also take the following steps to prevent damage from electrostatic discharge (ESD):
1. When unpacking a static-sensitive component from its shipping carton, do not remove the component from the
antistatic packing material until you are ready to install the component in your system. Just before unwrapping the
antistatic packaging, be sure to discharge static electricity from your body.
2. When transporting a sensitive component, first place it in an antistatic container or packaging.
3. Handle all sensitive components in a static-safe area. If possible, use antistatic floor pads, workbench pads and an
antistatic grounding strap.
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DES-3550 Fast Ethernet Layer 2 Switch
Section 1
Introduction
Ethernet Technology
Switch Description
Features
Ports
Front-Panel Components
Side Panel Description
Rear Panel Description
Gigabit Combo Ports
Ethernet Technology
Fast Ethernet Technology
Fast Ethernet
The growing importance of LANs and the increasing complexity of desktop computing applications are fueling the need
for high performance networks. A number of high-speed LAN technologies are proposed to provide greater bandwidth and
improve client/server response times. Among them, Fast Ethernet, or 100BASE-T, provides a non-disruptive, smooth
evolution from 10BASE-T technology.
100Mbps Fast Ethernet is a standard specified by the IEEE 802.3 LAN committee. It is an extension of the 10Mbps
Ethernet standard with the ability to transmit and receive data at 100Mbps, while maintaining the Carrier Sense Multiple
Access with Collision Detection (CSMA/CD) Ethernet protocol.
Gigabit Ethernet Technology
Gigabit Ethernet is an extension of IEEE 802.3 Ethernet utilizing the same packet structure, format, and support for
CSMA/CD protocol, full duplex, flow control, and management objects, but with a tenfold increase in theoretical
throughput over 100Mbps Fast Ethernet and a one hundred-fold increase over 10Mbps Ethernet. Since it is compatible with
all 10Mbps and 100Mbps Ethernet environments, Gigabit Ethernet provides a straightforward upgrade without wasting a
company's existing investment in hardware, software, and trained personnel.
The increased speed and extra bandwidth offered by Gigabit Ethernet are essential to coping with the network bottlenecks
that frequently develop as computers and their busses get faster and more users use applications that generate more traffic.
Upgrading key components, such as your backbone and servers to Gigabit Ethernet can greatly improve network response
times as well as significantly speed up the traffic between your subnetworks.
Gigabit Ethernet enables fast optical fiber connections to support video conferencing, complex imaging, and similar data-
intensive applications. Likewise, since data transfers occur 10 times faster than Fast Ethernet, servers outfitted with Gigabit
Ethernet NIC's are able to perform 10 times the number of operations in the same amount of time.
In addition, the phenomenal bandwidth delivered by Gigabit Ethernet is the most cost-effective method to take advantage
of today and tomorrow's rapidly improving switching and routing internetworking technologies.
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DES-3550 Fast Ethernet Layer 2 Switch
Switching Technology
Another key development pushing the limits of Ethernet technology is in the field of switching technology. A switch
bridges Ethernet packets at the MAC address level of the Ethernet protocol transmitting among connected Ethernet or Fast
Ethernet LAN segments.
Switching is a cost-effective way of increasing the total network capacity available to users on a local area network. A
switch increases capacity and decreases network loading by making it possible for a local area network to be divided into
different segments, which are not competing with each other for network transmission capacity, and therefore decreasing
the load on each segment.
The Switch acts as a high-speed selective bridge between the individual segments. Traffic that needs to go from one
segment to another (from one port to another) is automatically forwarded by the Switch, without interfering with any other
segments (ports). This allows the total network capacity to be multiplied, while still maintaining the same network cabling
and adapter cards.
For Fast Ethernet or Gigabit Ethernet networks, a switch is an effective way of eliminating problems of chaining hubs
beyond the "two-repeater limit." A switch can be used to split parts of the network into different collision domains, for
example, making it possible to expand your Fast Ethernet network beyond the 205-meter network diameter limit for
100BASE-TX networks. Switches supporting both traditional 10Mbps Ethernet and 100Mbps Fast Ethernet are also ideal
for bridging between existing 10Mbps networks and new 100Mbps networks.
Switching LAN technology is a marked improvement over the previous generation of network bridges, which were
characterized by higher latencies. Routers have also been used to segment local area networks, but the cost of a router and
the setup and maintenance required make routers relatively impractical. Today's switches are an ideal solution to most
kinds of local area network congestion problems.
Switch Description
The DES-3550 is equipped with unshielded twisted-pair (UTP) cable ports providing dedicated 10 or 100 Mbps bandwidth.
The Switch has 48 UTP ports and Auto MDI-X/MDI-II convertible ports that can be used for uplinking to another switch.
These ports can be used for connecting PCs, printers, servers, hubs, routers, switches and other networking devices. The
dual speed ports use standard twisted-pair cabling and are ideal for segmenting networks into small, connected
subnetworks for superior performance. Each 10/100 port can support up to 200 Mbps of throughput in full-duplex mode.
In addition, the Switch has 2 Mini-GBIC combo ports. These two gigabit combo ports are ideal for connecting to a server
or network backbone.
This stand-alone Switch enables the network to use some of the most demanding multimedia and imaging applications
concurrently with other user applications without creating bottlenecks. The built-in console interface can be used to
configure the Switch's settings for priority queuing, VLANs, and port trunk groups, port monitoring, and port speed.
Features
IEEE 802.3 10BASE-T compliant•
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IEEE 802.3u 100BASE-TX compliant
IEEE 802.1p Priority Queues
IEEE 802.3x flow control in full duplex mode
IEEE 802.3ad Link Aggregation Control Protocol support.
IEEE 802.1x Port-based and MAC-based Access Control
IEEE 802.1Q VLAN
IEEE 802.1D Spanning Tree, IEEE 802.1W Rapid Spanning Tree and IEEE 802.1s Multiple Spanning Tree
support
Access Control List (ACL) support
Single IP Management support
Access Authentication Control utilizing TACACS, XTACACS and TACACS+
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DES-3550 Fast Ethernet Layer 2 Switch
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Simple Network Time Protocol support
MAC Notification support
Asymmetric VLAN support
System and Port Utilization support
System Log Support
High performance switching engine performs forwarding and filtering at full wire speed, maximum 14, 881
packets/sec on each 10Mbps Ethernet port, and maximum 148,810 packet/sec on 100Mbps Fast Ethernet port.
Full- and half-duplex for both 10Mbps and 100Mbps connections. Full duplex allows the switch port to
simultaneously transmit and receive data. It only works with connections to full-duplex-capable end stations and
switches. Connections to a hub must take place at half-duplex
Support broadcast storm filtering
Non-blocking store and forward switching scheme capability to support rate adaptation and protocol conversion
Supports by-port Egress/Ingress rate control.
Efficient self-learning and address recognition mechanism enables forwarding rate at wire speed
Support port-based enable and disable
Address table: Supports up to 8K MAC addresses per device
Supports a packet buffer of up to 3 Mbits
Supports Port-based VLAN Groups
Port Trunking with flexible load distribution and fail-over function
IGMP Snooping support
SNMP support
Secure Sockets Layer (SSL) and Secure Shell (SSH) support
Port Mirroring support
MIB support for:
RFC1213 MIB II
RFC1493 Bridge
RFC1757 RMON
RFC1643 Ether-like MIB
RFC2233 Interface MIB
Private MIB
RFC2674 for 802.1p
IEEE 802.1x MIB
RS-232 DCE console port for Switch management
Provides parallel LED display for port status such as link/act, speed, etc.
Ports
Forty-eight (48) high-performance (MDI-X/MDI-II) ports for connecting to end stations, servers, hubs and other
networking devices.
All UTP ports can auto-negotiate between 10Mbps and 100Mbps, half-duplex and full duplex, and feature flow
control.
3

DES-3550 Fast Ethernet Layer 2 Switch
Two 1000BASE-T Mini-GBIC combo ports for connecting to another switch, server, or network backbone.•
• RS-232 DCE Diagnostic port (console port) for setting up and managing the Switch via a connection to a
console terminal or PC using a terminal emulation program.
NOTE: For customers interested in D-View, D-Link Corporation's
proprietary SNMP management software, go to the D-Link Website
(www.dlink.com.cn) and download the software and manual.
Front-Panel Components
The front panel of the Switch consists of LED indicators for power and for each 10/100 Mbps twisted-pair ports, and two
1000BASE-T Mini-GBIC ports.
DES-3550
Figure 1- 1. Front Panel View of the DES-3550 as shipped
Comprehensive LED indicators display the status of the Switch and the network.
LED Indicators
The Switch supports LED indicators for Power, Console, RPS and Port LEDs. The following shows the LED indicators for
the Switch along with an explanation of each indicator.
Figure 1- 2. LED Indicators
LED Description
Power This LED will light green after the Switch is powered on to indicate the ready state of the
device. The indicator is dark when the Switch is powered off.
Console This LED should blink during the Power-On Self Test (POST). When the POST is finished,
the LED goes dark. This indicator is lit sold green when the Switch is being logged into via
out-of-band/local console management through the RS-232 console port in the back of the
Switch using a straight-through serial cable.
RPS This LED will be lit when the redundant power supply is present and in use. Otherwise it will
remain dark.
4

DES-3550 Fast Ethernet Layer 2 Switch
Port LEDs One row of LEDs for each port is located above the ports on the front panel. The first LED is
for the top port and the second one is for the bottom ports. These port LEDs will light two
different colors for 10M and 100M.
•
•
Amber - For speeds of 10 Mbps. A solid light denotes activity on the port while a
blinking light indicates a valid link.
Green - For speeds of 100 Mbps. A solid light denotes activity on the port while a
blinking light indicates a valid link.
100M/10M These LEDs will light steady green to indicate that the port is transferring data at 100Mbps.
Gigabit Ports The Switch's two Mini GBIC ports have their own corresponding LEDs:
Speed - This LED will light solid green when the port is transferring at a rate of 1000Mbps.
When dark, the port is transferring at 10/100Mbps.·
Link/Act - This LED will light solid green when there is a valid link. A blinking LED indicates
current activity on the port. A dark LED indicates no activity on the port.
Rear Panel Description
The rear panel of the Switch contains an AC power connector.
Figure 1- 3. Rear panel view of the Switch
The AC power connector is a standard three-pronged connector that supports the power cord. Plug-in the female connector
of the provided power cord into this socket, and the male side of the cord into a power outlet. The Switch automatically
adjusts its power setting to any supply voltage in the range from 100 ~ 240 VAC at 50 ~ 60 Hz.
The rear panel also includes an outlet for an optional external power supply. When power fails, the optional external RPS
will take over all the power immediately and automatically.
Side Panel Description
The right-hand side panel of the Switch contains a system fan, while the left hand panel includes a system fan and a heat
vent.
The system fans are used to dissipate heat. The sides of the system also provide heat vents to serve the same purpose. Do
not block these openings, and leave at least 6 inches of space at the rear and sides of the Switch for proper ventilation. Be
reminded that without proper heat dissipation and air circulation, system components might overheat, which could lead to
system failure.
5

DES-3550 Fast Ethernet Layer 2 Switch
Figure 1- 4. Side Panels
Gigabit Combo Ports
In addition to the 48 10/100 Mbps ports, the Switch features two Gigabit Ethernet Combo ports. These two ports are
1000BASE-T copper ports (provided) and Mini-GBIC ports (optional). See the diagram below to view the two Mini-GBIC
port modules being plugged into the Switch. Please note that although these two front panel modules can be used
simultaneously, the ports must be different. The GBIC port will always have the highest priority.
Figure 1- 5. Mini-GBIC modules plug-in to the Switch
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