D-Link DGS-1248T - Switch User manual

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D-Link™ DGS-1248T
WebSmart 48-Port 10/100/1000Mbps + 4
Combo SFP(Mini GBIC) Gigabit Switch
Manual
Second Edition
Building Networks for People
RECYCLABLE
Information in this document is subject to change without notice.
© 2004 D-Link Computer Corporation. All rights reserved.

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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!

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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.
VCCI Warning

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TABLE OF CONTENT
About This Manual ......................................................................................... 1
Purpose ....................................................................................................... 1
Terms/Usage ............................................................................................... 1
Introduction..................................................................................................... 2
Gigabit Ethernet Technology...................................................................... 2
Fast Ethernet Technology ........................................................................... 3
Switching Technology ................................................................................ 3
VLAN (Virtual Local Area Network)......................................................... 4
Features....................................................................................................... 4
Unpacking and Installation ............................................................................. 6
Unpacking................................................................................................... 6
Installation .................................................................................................. 6
Rack Mounting ........................................................................................... 7
Connecting Network Cable......................................................................... 8
AC Power.................................................................................................... 8
Identifying External Components ................................................................... 9
Front Panel.................................................................................................. 9
LED Indicator ............................................................................................. 9
Reset ........................................................................................................... 9
Rear Panel................................................................................................. 10
Understanding LED Indicators ..................................................................... 11
Power and System LEDs .......................................................................... 11
Ports 1~48 Status LEDs ............................................................................ 11
mini-GBIC Port 45F ~ 48F LEDs............................................................. 12
Configuration ................................................................................................ 13
Installing the Web Management Utility.................................................... 13
Discovery List........................................................................................... 14
Monitor List .............................................................................................. 14

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Device Setting........................................................................................... 16
Toolbar...................................................................................................... 17
Configuring the Switch ............................................................................. 18
Login......................................................................................................... 18
Setup Menu ............................................................................................... 20
Configuring Setup Setting......................................................................... 20
Port Settings .......................................................................................... 21
VLAN Settings (Virtual Local Area Network) ..................................... 22
Trunk Setting ........................................................................................ 24
Mirror Setting........................................................................................ 25
Spanning Tree Setting........................................................................... 26
SNMP Setting ....................................................................................... 28
Jumbo Frame Setting ............................................................................ 32
QoS Setting ........................................................................................... 32
Device Status ........................................................................................ 33
Statistics ................................................................................................ 34
System Setting ...................................................................................... 36
Trap Setting........................................................................................... 37
Password Setting................................................................................... 38
Backup Setting...................................................................................... 38
Reset Setting ......................................................................................... 39
Logout....................................................................................................... 39
Technical Specifications ............................................................................... 40
Warranty and Registration Information
Warranty and Registration Information (USA Only)

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ABOUT THIS MANUAL
Congratulations on your purchase of the DGS-1248T Web Smart 48-Port
10/100/1000Mbps Gigabit Switch. This device integrates 1000Mbps Gigabit
Ethernet, 100Mbps Fast Ethernet, and 10Mbps Ethernet network capabilities
in a highly flexible package.
Purpose
This manual discusses how to install your 48-Port 10/100/1000Mbps Gigabit
Web Smart Switch.
Terms/Usage
In this manual, the term “Switch” (first letter upper case) refers to your Web
Smart Switch, and “switch” (first letter lower case) refers to other Ethernet
switches.

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INTRODUCTION
This chapter describes the features of the DGS-1248T Web Smart 48-Port
10/100/1000Mbps Gigabit Switch and some background information about
Ethernet/Fast Ethernet/Gigabit Ethernet switching technology.
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 100-Mbps Fast Ethernet and a hundredfold
increase over 10-Mbps Ethernet. Since it is compatible with all 10-Mbps and
100-Mbps 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 subnets.
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. And with
expected advances in the coming years in silicon technology and digital signal
processing that will enable Gigabit Ethernet to eventually operate over
unshielded twisted-pair (UTP) cabling, outfitting your network with a
powerful 1000-Mbps-capable backbone/server connection creates a flexible
foundation for the next generation of network technology products.

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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 have been proposed to provide
greater bandwidth and improve client/server response times. Among them,
100BASE-T (Fast Ethernet) provides a non-disruptive, smooth evolution from
the current 10BASE-T technology. The non-disruptive and smooth evolution
nature, and the dominating potential market base, virtually guarantees
cost-effective and high performance Fast Ethernet solutions.
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 CSMA/CD
Ethernet protocol. Since the 100Mbps Fast Ethernet is compatible with all
other 10Mbps Ethernet environments, it provides a straightforward upgrade
and takes advantage of the existing investment in hardware, software, and
personnel training.
Switching Technology
Another approach to pushing beyond the limits of Ethernet technology is the
development 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 dividing a local area network into different
segments, which do not compete with each other for network transmission
capacity.
The switch acts as a high-speed selective bridge between the individual
segments. The switch, without interfering with any other segments,
automatically forwards traffic that needs to go from one segment to another.
By doing this the total network capacity is multiplied, while still maintaining
the same network cabling and adapter cards.

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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, the setup, and maintenance required make routers relatively impractical.
Today switches are an ideal solution to most kinds of local area network
congestion problems.
VLAN (Virtual Local Area Network)
A VLAN is a group of end-stations that are not constrained by their physical
location and can communicate as if a common broadcast domain, a LAN. The
primary utility of using VLAN is to reduce latency and need for routers, using
faster switching instead. Other VLAN utility includes:
Security: Security is increased with the reduction of opportunity in
eavesdropping on a broadcast network because data will be switched to only
those confidential users within the VLAN.
Cost Reduction: VLANs can be used to create multiple broadcast domains,
thus eliminating the need of expensive routers.
Features
48×10/100/1000Mbps Auto-negotiation Gigabit Ethernet ports
4 x 1000Mbps SFP(Mini GBIC) (Auto-Sense) for optional SFP(Mini
GBIC) transceiver to extend distance, share with 4 1000BASE-T ports
All RJ-45 ports support auto MDI/MDIX, so there is no need to use
cross-over cables or an up-link port
Half-duplex transfer mode for connection speed 10Mbps and 100Mbps
Full-duplex transfer mode for connection speed of 10Mbps, 100Mbps,
and 1000Mbsps
Wire speed reception and transmission
Store-and-Forward switching scheme capability to support rate
adaptation and ensure data integrity
Up to 16K unicast addresses entities per device, self-learning, and table
aging
1632KBytes packet buffer

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Supports IEEE 802.3x flow control for full-duplex mode ports
Supports 802.1Q VLAN
Supports IEEE 802.1p QoS
Supports Trunk
Supports Port-mirroring
Support Jumbo-frame setting
Supports IEEE 802.1D Spanning Tree protocol
Support Simple Network Management Protocol (SNMP)
Supports MIB for:
RFC1213 MIB II.
Private MIB.
Supports Port-setting for Speed/Disable, Flow control
Easy configuration via Web Browser
Easy setting via Web Management Utility
Standard 19” Rack-mount size

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UNPACKING AND INSTALLATION
This chapter provides unpacking and installation information for the Switch.
Unpacking
Open the shipping cartons of the Switch and carefully unpacks its contents.
The carton should contain the following items:
One DGS-1248T Web Smart 48-Port 10/100/1000Mbps Gigabit
Switch
One AC power cord, suitable for your area’s electrical power
connections
Four rubber feet to be used for shock cushioning
Screws and two mounting brackets
CD-ROM with Web Management Utility and Manual
If any item is found missing or damaged, please contact your local reseller for
replacement.
Installation
The site where you install the hub stack may greatly affect its performance.
When installing, consider the following pointers:
Install the Switch in a fairly cool and dry place. See Technical Specifications
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.
Leave at least 10cm of space at the front and rear of the hub for ventilation.
Install the Switch on a sturdy, level surface that can support its weight, or in an
EIA standard-size equipment rack. For information on rack installation, see the
next section, Rack Mounting.

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When installing the Switch on a level surface, attach the rubber feet to the
bottom of each device. The rubber feet cushion the hub and protect the hub
case from scratching.
Figure 1. Attach the adhesive rubber pads to the bottom
Rack Mounting
The Switch can be mounted in an EIA standard-size, 19-inch rack, which can
be placed in a wiring closet with other equipment. Attach the mounting
brackets at the Switch’s front panel (one on each side), and secure them with
the provided screws.
Figure 2. Combine the Switch with the provided screws
Then, use screws provided with the equipment rack to mount each Switch in
the rack.
Figure 3. Mount the Switch in the rack

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Connecting Network Cable
The Switch supports 1000Mbps Gigabit Ethernet that runs in
Auto-negotiation mode and 10Mbps Ethernet or 100Mbps Fast Ethernet that
runs both in half- and full-duplex mode and 1000Mbps Gigabit Ethernet runs
in full-duplex mode using four pair of Category 5 Cable.
These RJ-45 ports are Auto-MDI type port. The Switch can auto transform to
MDI-II or MDI-X type, so you can just make an easy connection that without
worrying if you are using a standard or crossover RJ45 cable.
There are 4 additional SFP/mini-GBIC slots for optional SFP/mini-GBIC
modules.
AC Power
The Switch uses the AC power supply 100-240V AC, 50-60 Hz. The power
switch is located at the rear of the unit adjacent to the AC power connector
and the system fan. The Switch’s power supply will adjust to the local power
source automatically and may be turned on without having any or all LAN
segment cables connected.

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IDENTIFYING EXTERNAL COMPONENTS
This chapter describes the front panel, rear panel, and LED indicators of the
Switch.
Front Panel
The figure below shows the front panels of the Switch.
10/100/1000 Base-T Twisted-Pair Ports w/ LED Indicators
┌─────────────────────────────┐
└──┘
SFP(Mini GBIC)Ports
Figure 4. Front panel of 48-Port Gigabit Ethernet Switch
LED Indicator
Comprehensive LED indicators display the status of the Switch and the
network (see the LED Indicators chapter below).
1000BASE-T Twisted Pair Ports (Port 1~48)
The DGS-1248T is equipped with fourty-eight Gigabit twisted pair ports that
are auto negotiable 10/100/1000Mbps and also support auto MDI/MDIX
crossover detection. These ports can operate in half- and full-duplex modes.
SFP(Mini GBIC) Ports (Option Port 45~48)
The Switch is equipped with Four SFP(Mini GBIC) ports, supporting
optional 1000BASE-X SFP(Mini GBIC) transceivers.
Note: When the port is set to “Forced Mode”, Auto MDI/MDIX will be
disabled.
Reset
The Reset button is used to reset all settings back to the factory defaults.
Note: Be sure that you record the settings of your device, or else all settings
will be erased when pressing the “Reset” button.

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Rear Panel
Figure 5. Rear panel of the Switch
AC Power Connector:
This is a three-pronged connector that supports the power cord. Plug in the
female connector of the provided power cord into this connector, and the
male into a power outlet. Supported input voltages range from 100-240V AC
at 50-60Hz.

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UNDERSTANDING LED INDICATORS
The front panel LEDs provides instant status feedback, and helps monitor and
troubleshoot when needed.
Figure 6. LED indicators of the Switch
Power and System LEDs
POWER: System Power Indicator
On : When the Power LED lights on, the Switch is receiving power.
Off :
When the Power turns off or the power cord has an improper
connection.
CPU: Management Indicator
Blinking : When the CPU is working, the CPU LED is blinking.
On/Off : The CPU is not working.
Ports 1~48 Status LEDs
Link/ACT: Link/Activity
On : When the Link/ACT LED lights on, the respective port is successfully
connected to an Ethernet network.
Blinking : When the Link/ACT LED is blinking, the port is transmitting or
receiving data on the Ethernet network.
Off : There is no link.

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Speed:
Green : When the Speed LED lights green, the respective port is connected to a
1000Mbps Gigabit Ethernet network.
Amber : When the Speed LED lights amber, the respective port is connected to a
100Mbps Fast Ethernet network.
Off : When the Speed LED lights off, the respective port is connected to a
10Mbps Fast Ethernet network.
mini-GBIC Port 45F ~ 48F LEDs
Link/ACT:
On : When the mini-GBIC module is installed and connected to a
network, the Link LED lights on.
Blinking When the LED is blinking, the port is transmitting or receiving data
on the network.
Off : No mini-GBIC module is installed or connected to a network.

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CONFIGURATION
Through the Web Browser you can configure the Switch functions such as
VLAN, Trunking, QoS… etc.
With the attached Web Management Utility, you can easily discover all Web
Managed Switches, assign the IP Address, change the password, and upgrade
with new firmware.
Installing the Web Management Utility
The following provides instructions guiding you through the installations of
the Web Management utility.
1. Insert the Utility CD in the CD-ROM Drive.
2. From the Start menu on the Windows desktop, choose Run.
3. In the Run dialog box, type D:\Web Management Utility\setup.exe (D:\
depends where your CD-ROM drive is located) and click OK.
4. Follow the on-screen instructions to install the utility.
5. Upon completion, go to Program Files -> web_management_utility and
execute the Web Management utility. (Figure 7.)
Figure 7. Web Management Utility
The Web Management Utility was divided into four parts, Discovery List,
Monitor List,Device Setting, and Toolbar function, for detailed instructions,
follow the section below.

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Discovery List
This is the list where you can discover all the Web managed devices in the
entire network.
By pressing the “Discovery” button, you can list all the Web Managed
devices in the discovery list.
Double click or press the “Add to monitor list” button to select a device from
the Discovery List to the Monitor List.
System word definitions in the Discovery List:
zMAC Address: Shows the device MAC Address.
zIP Address: Shows the current IP address of the device.
zProtocol version: Shows the version of the Utility protocol.
zProduct Name: Shows the device product name.
zSystem Name: Shows the appointed device system name.
zLocation: Shows where the device is located.
zTrap IP: Shows the IP where the Trap is to be sent.
zSubnet Mask: Shows the Subnet Mask set of the device.
zGateway: Shows the Gateway set of the device.
Monitor List
All the Web Smart Devices in the Monitor List can be monitored; you can
also receive traps and show the status of the device.
System word definitions in the Monitor List:
zS: Shows the system symbol of the WebSmart device,
represents a device that is not alive.
zIP Address: Shows the current IP address of the device.
zMAC Address: Shows the device MAC Address.
zProtocol version: Shows the version of the Utility protocol.
zProduct Name: Shows the device product name.
zSystem Name: Shows the appointed device system name.

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zLocation: Shows where the device is located.
zTrap IP: Shows the IP where the Trap is to be sent.
zSubnet Mask: Shows the Subnet Mask set of the device.
zGateway: Shows the Gateway set of the device.
View Trap: The Trap function can receive the events that occur on the
Switch in the Monitor List.
There is a light indicator behind the “View Trap” button. When the light is
green, it means that there is no trap transmitted, and when it is red, it means
that there is new trap transmitted, reminding us to view the trap. (Figure 8)
Figure 8.
When the “View Trap” button is clicked, a Trap Information window will
pop up. It will display the trap information including the Symbol, Time,
Device IP, and the Event occurred. (Figure 9)
The symbol “ ” represents the trap signal; this symbol will disappear after
you review and click on the event record.
Figure 9.
Note: In order to receive Trap information, the Switch has to be configured
with Trap IP and Trap Events in the Web browser, which are available in the
Trap Setting Menu (see Page 45 for details).
Add Item: To add a device to the Monitor List manually, enter the IP
Address of the device that you want to monitor.
Delete Item: To delete the device in the Monitor List.