D-Link DES-1048G User manual

D-Link ™ DES-1048G
48-Port 10/100Base-T and 2 Mini-GBIC Port
Unmanaged Ethernet Switch
Manual
Second Edition
Building Networks for People
RECYCLABLE

____________________
Information in this document is subject to change without notice.
© 2003 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.
FCC Warning
This equipment has been tested and found to comply with the limits for a Class A digital device, pursuant to Part 15 of the FCC Rules. These
limits are designed to provide reasonable protection against harmful interference when the equipment is operated in a commercial
environment. This equipment generates, uses, and can radiate radio frequency energy and, if not installed and used in accordance with this
user’s guide, may cause harmful interference to radio communications. Operation of this equipment in a residential area is likely to cause
harmful interference in which case the user will be required to correct the interference at his own expense.
CE Mark Warning
This is a Class A product. In a domestic environment, this product may cause radio interference in which case the user may be required to
take adequate measures.
Warnung!
Dies ist ein Produkt der Klasse A. Im Wohnbereich kann dieses Produkt Funkstoerungen verursachen. In diesem
Fall kann vom Benutzer verlangt werden, angemessene Massnahmen zu ergreifen.
Precaución!
Este es un producto de Clase A. En un entorno doméstico, puede causar interferencias de radio, en cuyo case,
puede requerirse al usuario para que adopte las medidas adecuadas.
Attention!
Ceci est un produit de classe A. Dans un environnement domestique, ce produit pourrait causer des interférences
radio, auquel cas l`utilisateur devrait prendre les mesures adéquates.
Attenzione!
Il presente prodotto appartiene alla classe A. Se utilizzato in ambiente domestico il prodotto può causare
interferenze radio, nel cui caso è possibile che l`utente debba assumere provvedimenti adeguati.

CONTENTS
INTRODUCTION..................................................................................................................................................1
ETHERNET TECHNOLOGY......................................................................................................................................1
SWITCHING TECHNOLOGY ....................................................................................................................................1
SWITCH DESCRIPTION ...........................................................................................................................................2
Features ...........................................................................................................................................................2
Ports.................................................................................................................................................................3
Mini-GBIC Port Insert .....................................................................................................................................3
FRONT-PANEL COMPONENTS ................................................................................................................................3
LED Indicators.................................................................................................................................................3
REAR PANEL DESCRIPTION ...................................................................................................................................4
SIDE PANEL DESCRIPTION.....................................................................................................................................4
INSTALLATION ...................................................................................................................................................6
PACKAGE CONTENTS ............................................................................................................................................6
BEFORE YOU CONNECT TO THE NETWORK ...........................................................................................................6
INSTALLING THE SWITCH WITHOUT THE RACK.....................................................................................................7
INSTALLING THE SWITCH IN A RACK.....................................................................................................................7
POWER ON............................................................................................................................................................8
Power Failure ..................................................................................................................................................8
CONNECTING THE SWITCH ...........................................................................................................................9
SWITCH TO END NODE .........................................................................................................................................9
SWITCH TO HUB OR SWITCH .................................................................................................................................9
CONNECTING TO NETWORK BACKBONE OR SERVER ..........................................................................................10
TECHNICAL SPECIFICATIONS.....................................................................................................................11
GLOSSARY..........................................................................................................................................................13
WARRANTY AND REGISTRATION INFORMATION................................................................................16
(ALL COUNTRIES AND REGIONS EXCLUDING USA) .............................................................................................16
LIMITED WARRANTY ..........................................................................................................................................18
(USA ONLY).......................................................................................................................................................18
USA ...........................................................................................................................................................................21
D-LINK U.S.A..................................................................................................................................................................21
CANADA ......................................................................................................................................................................21
EUROPE (U. K.)................................................................................................................................................................21
GERMANY ....................................................................................................................................................................21
FRANCE ......................................................................................................................................................................21
Netherlands .............................................................................................................................................................21
Weena 290 ..............................................................................................................................................................21
Belgium ................................................................................................................................................................21
ITALY.........................................................................................................................................................................21
SWEDEN ......................................................................................................................................................................21
DENMARK ....................................................................................................................................................................21
NORWAY ......................................................................................................................................................................21
SINGAPORE...................................................................................................................................................................21
JAPAN ........................................................................................................................................................................21

INDIA .........................................................................................................................................................................21
MIDDLE EAST (DUBAI) .......................................................................................................................................................21
LATINAMERICA ..............................................................................................................................................................21
SOUTH AFRICA ...............................................................................................................................................................21
RUSSIA........................................................................................................................................................................21
TAIWAN ......................................................................................................................................................................21
HEADQUARTERS .............................................................................................................................................................21

D-Link DES-1048G Unmanaged Layer 2 Ethernet Switch
Preface
The DES-1048G User’s Guide is divided into sections that describe the system installation and operating
instructions with examples.
Section 1, Introduction – A description of the physical features of the switch, including LED indicators,
ports, and panel descriptions.
Section 2, Installation – A description of the physical installation of the switch as well as the packing list.
Section 3, Connecting the Switch – A description of the physical installation of the switch including
connecting the switch to the network.
Appendix A, Technical Specifications – The technical specifications of the DES-1048G.
Glossary – Lists definitions for terms and acronyms used in this document.
Intended Readers
The DES-1048G User Guide contains information for setup and management and of the DES-1048G switch.
This guide is intended for network managers familiar with network management concepts and terminology.
Notes, Notices, and Cautions
NOTE: A NOTE indicates important information that helps you make
better use of your device.
NOTICE: A NOTICE indicates either potential damage to hardware or loss
of data and tells you how to avoid the problem.
CAUTION: A CAUTION indicates a potential for property damage,
personal injury, or death.
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D-Link DES-1048G Unmanaged Layer 2 Ethernet 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.
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.
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D-Link DES-1048G Unmanaged Layer 2 Ethernet Switch
Safety Instructions (continued)
• 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 remove the grounding prong from a cable. If you must use an extension cable,
use a 3-wire cable with properly grounded plugs.
• 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.
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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D-Link DES-1048G Unmanaged Layer 2 Ethernet Switch
Safety Instructions (continued)
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.
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 and
workbench pads and an antistatic grounding strap.
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D-Link DES-1048G Unmanaged Layer 2 Ethernet Switch
SECTION 1
Introduction
Ethernet Technology
Switch Description
Features
Ports
Front-Panel Components
Side Panel Description
Rear Panel Description
Ethernet Technology
Fast Ethernet Technology
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 is 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.
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
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D-Link DES-1048G Unmanaged Layer 2 Ethernet Switch
network to be divided into different segments which don’t compete with each other for network transmission
capacity, giving a decreased load on each.
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-1048G is a stand-alone unmanaged switch. It is equipped with forty-eight ports providing dedicated 10
or 100 Mbps bandwidth. These ports can be used for connecting PCs, servers, and hubs. The forty-eight dual
speed ports use standard twisted-pair cabling and are ideal for segmenting networks into small, connected
subnets. Each port can support up to 200 Mbps of throughput in full duplex mode. In addition, the Switch is
equipped with two Mini-GBIC fiber optic uplink ports enabling convenient access to a server or network
backbone for all the clients served by the Switch. 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 individually configure each port for Speed, Full or Half
duplex operation, and IEEE 802.3x Flow Control in full duplex mode.
Features
• Forty-eight 10/100 Mbps ports for connections to other LAN switches and hubs, or directly to power
users
• IEEE 802.3 compliant 10BASE-T
• IEEE 802.3u compliant 100BASE-TX
• IEEE 802.3z compliant (for mini-GBIC port insert)
• Full and half-duplex for both 10Mbps and 100Mbps connections. Full duplex allows the switch port to
simultaneously transmit and receive data, and only works with connections to full-duplex capable end
stations and switches. Connections to a hub must take place at half-duplex
• 2 optional Mini-GBIC ports located on the front panel. The Mini-GBIC ports operate at full duplex only
• Store and forward switching scheme capability to support rate adaptation and protocol conversion
• Data forwarding rate 14,880 pps per port at 100% of wire-speed for 10Mbps speed
• Data forwarding rate 148,809 pps per port at 100% of wire-speed for 100Mbps speed
• Data forwarding rate 1,488,090 pps per port at 100% of wire-speed for 1000Mbps speed
• Data filtering rate eliminates all error packets, runts, etc. at 14,880 pps per port at 100% of wire-speed
for 10Mbps speed
• Data filtering rate eliminates all error packets, runts, etc. at 148,810 pps per port at 100% of wire-speed
for 100Mbps speed
• Data filtering rate eliminates all error packets, runts, etc. at 1,488,100 pps per port at 100% of wire-
speed for 1000Mbps speed
• Layer 2 switching based on MAC address
• Address handling: auto-learning, auto-aging
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D-Link DES-1048G Unmanaged Layer 2 Ethernet Switch
• MAC Address table: Support addresses up to 8K
• A packet buffer size of 2M-bytes per device (embedded)
• Auto-negotiation (NWay) between 10Mbps/100Mbps, half-duplex or full duplex for 10/100BASE-T
ports
Ports
• Forty-eight high-performance NWay Fast Ethernet ports, all of which operate at 10/100 Mbps for
connections to end stations, servers, and hubs. All ports can auto-negotiate between 10Mbps or
100Mbps and full or half duplex
• Two Mini-GBIC ports for connecting to another switch, server or network backbone
Mini-GBIC Port Insert
• 2 mini-GBIC port slots available
• Accepts 1000BASE-SX, 1000BASE-LX and 1000LH
• Hot swappable
• IEEE 802.3x compliant Flow Control support for full duplex operation
• Supports full duplex 1000Mbps operation only
Front-Panel Components
The front panel of the Switch consists of LED indicators, 48 (10/100 Mbps) Fast Ethernet ports and two
indicators for the mini-GBIC ports.
Figure 1-1. Front Panel View of the switch
Comprehensive LED indicators display the status of the switch and the network.
LED Indicators
The LED indicators of the Switch include Power and Link/Act. The following shows the LED indicators for the
Switch along with an explanation of each indicator.
Figure 1-2. LED Indicators
Power This indicator on the front panel should be lit during the Power-On Self Test (POST).
It will li
g
ht
g
reen a
pp
roximatel
y
2 seconds after the switch is
p
owered on to indicate
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D-Link DES-1048G Unmanaged Layer 2 Ethernet Switch
the ready state of the device.
Link/Act
Each on-board port has a corresponding indicator. This will light steady green for a
valid link and blink whenever there is reception or transmission (i.e. Activity--Act) of
data occurring at a 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 system fan is used to dissipate heat. 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
end of the cord into a power outlet. The switch automatically adjusts its power setting to any supply voltage in
the range from 100~120; 200~240 VAC at 50 ~ 60 Hz.
Side Panel Description
The sides of the system provide heat vents that help to dissipate heat. 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.
Figure 1-4. Side Panels (the left-hand panel is pictured on top)
Mini-GBIC Gigabit Ports
In addition to the 48 10/100Mpbs ports, the Switch features two mini-GBIC ports. See the diagram below to
view the two mini-GBIC port modules being plugged into the Switch.
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D-Link DES-1048G Unmanaged Layer 2 Ethernet Switch
Figure 2-5. Mini-GBIC port modules being plugged into the Switch (Note: Illustration purposes only;
modules are not included with the device.)
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D-Link DES-1048G Unmanaged Layer 2 Ethernet Switch
SECTION 2
Installation
Package Contents
Before You Connect to the Network
Installing the Switch Without the Rack
Rack Installation
Power On
Package Contents
Open the shipping carton of the Switch and carefully unpack its contents. The carton should contain the
following items:
One DES-1048G Stand-alone Switch•
•
•
•
•
•
•
•
•
•
•
•
•
One AC power cord
This User’s Guide on CD-ROM
Registration Card
Mounting Kit (two brackets and screws)
Four rubber feet with adhesive backing
If any item is found missing or damaged, please contact your local D-Link reseller for replacement.
Before You Connect to the Network
The site where you install the Switch may greatly affect its performance. Please follow these guidelines for
setting up the Switch.
Install the Switch on a sturdy, level surface that can support at least 3 kg of weight. Do not place heavy
objects on the Switch.
The power outlet should be within 1.82 meters (6 feet) of the Switch.
Visually inspect the power cord and see that it is fully secured to the AC power port.
Make sure that there is proper heat dissipation from and adequate ventilation around the switch. Leave at
least 10 cm of space at the front and rear of the Switch for ventilation.
Install the Switch in a fairly cool and dry place for the acceptable temperature and humidity operating
ranges.
Install the Switch in a site free from strong electromagnetic field generators (such as motors), vibration,
dust, and direct exposure to sunlight.
When installing the switch on a level surface, attach the rubber feet to the bottom of the device. The
rubber feet cushion the Switch, protect the casing from scratches and prevent it from scratching other
surfaces.
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D-Link DES-1048G Unmanaged Layer 2 Ethernet Switch
Installing the Switch Without the Rack
When installing the Switch on a desktop or shelf, the rubber feet included with the Switch should first be
attached. Attach these cushioning feet on the bottom at each corner of the device. Allow enough ventilation
space between the Switch and any other objects in the vicinity.
Figure 2-1. Prepare Switch for installation on a desktop or shelf
Installing the Switch in a Rack
The Switch can be mounted in a standard 19” rack. Use the following diagrams to guide you.
Figure 2-2. Fasten mounting brackets to Switch
Fasten the mounting brackets to the Switch using the screws provided. With the brackets attached securely, you
can mount the Switch in a standard rack as shown in Figure 2-3 on the following page.
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D-Link DES-1048G Unmanaged Layer 2 Ethernet Switch
Mounting the Switch in a Standard 19” Rack
Figure 2-3. Installing Switch in a rack
Power On
Plug one end of the AC power cord into the power connector of the Switch and the other end into the local power
source outlet.
Power Failure
As a precaution, in the event of a power failure, unplug the Switch. When power is resumed, plug the Switch
back in.
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D-Link DES-1048G Unmanaged Layer 2 Ethernet Switch
SECTION 3
Connecting The Switch
Switch To End Node
Switch To Hub or Switch
Connecting To Network Backbone or Server
NOTE: All 48 high-performance NWay Ethernet ports can support both MDI-II
and MDI-X connections.
Switch To End Node
End nodes include PCs outfitted with a 10, 100, or 10/100 Mbps RJ-45 Ethernet/Fast Ethernet Network Interface
Card (NIC) and most routers.
An end node can be connected to the Switch via a twisted-pair Category 3, 4, or 5 UTP/STP cable. The end node
should be connected to any of the ports of the Switch.
Figure 3-1. Switch connected to an end node
The Link/Act LEDs for each UTP port light green when the link is valid. The LED over the port label indicates
port speed of either 10 or 100 Mbps. A blinking LED on the bottom indicates packet activity on that port.
Switch to Hub or Switch
These connections can be accomplished in a number of ways using a normal cable
A 10BASE-T hub or switch can be connected to the Switch via a twisted-pair Category 3, 4 or 5
UTP/STP cable.
•
• A 100BASE-TX hub or switch can be connected to the Switch via a twisted-pair Category 5 UTP/STP
cable.
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D-Link DES-1048G Unmanaged Layer 2 Ethernet Switch
Figure 3-2. Switch connected to a port on a hub or switch using either a straight or crossover cable–
any normal cable is fine
Connecting To Network Backbone or Server
The mini-GBIC fiber optic ports are ideal for uplinking to a network backbone or network server via 1000BASE-
SX and 1000BASE-LX fiber optic cable. These ports operate at 1000 Mbps in full duplex mode only. Mini-
GBIC port modules can be installed or taken out without powering off or disconnecting the Switch.
Figure 3-3. Connecting to a server
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D-Link DES-1048G Unmanaged Layer 2 Ethernet Switch
Appendix A
Technical Specifications
General
Standard
IEEE 802.3 10BASE-T Ethernet
IEEE 802.3u 100BASE-TX Fast Ethernet
IEEE 802.3z 1000BASE-SX Gigabit Ethernet
IEEE 802.3x Flow Control
IEEE 802.3 Nway auto-negotiation
Protocols CSMA/CD
Data Transfer Rates:
Ethernet
Fast Ethernet
Gigabit Ethernet
Half-duplex Full-duplex
10 Mbps 20Mbps
100Mbps 200Mbps
2000Mpbs
Topology Star
Network Cables
10BASE-T
UTP Category 3, 4, 5 (100 meters max.)
EIA/TIA- 568 100-ohm STP (100 meters max.)
100BASE-TX
UTP Cat. 5 (100 meters max.)
EIA/TIA-568 100-ohm STP (100 meters max.)
1000BASE-SX
50/125µm Multimode Fiber-optics (550 meters max.)
62.5/125µm Multimode Fiber-optics (275 meters max.)
1000BASE-LX
50/125µm Multimode Fiber-optics (550 meters max.)
62.5/125µm Multimode Fiber-optics (275 meters max.)
Ports 48 10/100BASE-T Ethernet ports in front panel
2 1000Mbps Mini-GBIC ports
Physical & Environmental
AC Inputs: 100 - 240 VAC, 50/60 Hz (internal universal power supply)
Power Consumption: 24 watts maximum
DC Fan: 2 built-in 40 x 40 x 10 mm fans
Operating
Temperature: 0 to 40 degrees Celsius
Storage Temperature: -25 to 55 degrees Celsius
Humidity: Operating: 5% to 95% RH non-condensing
Storage: 0% to 95% RH non-condensing
Dimensions: 441 mm x 309 mm x 44 mm (1U), 19 inch rack-mount width
Weight: 3.9 Kg
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D-Link DES-1048G Unmanaged Layer 2 Ethernet Switch
EMI: FCC Class A, CE Class A
Safety: CSA International
Performance
Transmission Method: Store-and-forward
RAM Buffer: 2 Mbyte per device
Filtering Address
Table: 8K MAC address per device
Packet Filtering/
Forwarding Rate:
Full-wire speed for all connections.
14,880 pps for 10M and 148,809 pps for 100M
1,488,090 pps for 1000M
MAC Address
Learning: Automatic update.
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