D-Link 24-Port 10/100/1000Mbps Ethernet Switch... User manual

D-Link ™ DES-1024D
24-Port 10/100/1000Mbps
Ethernet Switch
Manual
Building Networks for People
RECYCLABLE
(November 2005)
P/N: 2907D1024D16008

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TABLE OF CONTENTS
About This Guide ......................................................... 1
PURPOSE ..........................................................................................1
TERMS/USAGE .................................................................................1
OVERVIEW OF THIS USER’S GUIDE................................................1
Introduction .................................................................. 2
FAST ETHERNET TECHNOLOGY.....................................................2
SWITCHING TECHNOLOGY.............................................................3
FEATURES ........................................................................................4
IEEE 801.1P AND QOS…...….……………………………………5
Unpacking and Setup.................................................... 4
UNPACKING .....................................................................................7
SETUP ...............................................................................................7
DESKTOP INSTALLATION................................................................8
RACK MOUNTING............................................................................8
Identifying External Components............................... 10
FRONT PANEL................................................................................10
REAR PANEL..................................................................................11
Technical Specifications ............................................. 12
Technical Specifications ............................................. 13

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ABOUT THIS GUIDE
Congratulations on your purchase of the DES-1024D 24-port
10/100Mbps Fast Ethernet Switch. This device integrates 100Mbps
Fast Ethernet and 10Mbps Ethernet network capabilities into one
highly flexible solution.
Purpose
This guide discusses how to install your DES-1024D.
Terms/Usage
In this guide, the term “Switch” (first letter upper case) refers to your 24-port
10/100Mbps Fast Ethernet Switch, and ”switch” (first letter lower case)
refers to other Ethernet switches.
Overview of this User’s Guide
Introduction. Describes the Switch and its features.
Unpacking and Installation.Helps you get started with the basic installation
of the Switch.
Identifying External Components. Describes the front panel, rear panel and
LED indicators of the Switch.
Technical Specifications. Lists the technical (general, physical and
environmental, and performance) specifications of the Switch.

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INTRODUCTION
This chapter describes the features of the DES-1024D and some background
information about Ethernet/Fast Ethernet switching technology.
Fast Ethernet Technology
Ethernet, along with its speedier counterpart Fast Ethernet, is the
most popular networking standard in use today. 100BaseT Fast
Ethernet is an extension of the 10BaseT Ethernet standard,
designed to raise the data transmission capacity of 10BaseT from
10Mbits/sec to 100Mbits/sec. An important strategy incorporated by
100BaseT is its use of the Carrier Sense Multiple Access with
Collision Detection (CSMA/CD) protocol - which is the same
protocol that 10BaseT uses - because of its ability to work with
several different types of cable, including basic twisted-pair wiring.
Both of these features play an important role in network
considerations, and they make 100BaseT an attractive migration
path for those networks based on 10BaseT. 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.

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Switching Technology
Switching is a cost-effective way of increasing the total network capacity
available to users on a LAN. If an Ethernet network begins to display
symptoms of congestion, low throughput, slow response times, and high rates
of collision, installing a switch to an network can preserve much or all of the
existing network's cabling and workstation interface card infrastructure while
still greatly enhancing the throughput for users. A switch is a viable solution
even if demanding applications, such as multimedia production and video
conferencing, are on the horizon. The most promising techniques, as well as
the best return on investment, could well consist of installing the right
mixture of Ethernet switches.
A switch increases capacity and decreases network loading by dividing a
local area network into different LAN segments. Dividing a LAN into
multiple segments is one of the most common ways of increasing available
bandwidth. If segmented correctly, most network traffic will remain within a
single segment, enjoying the full-line speed bandwidth of that segment.
Switches provide full-line speed, dedicated to bandwidth for all connections.
This is in contrast to the hubs, which use the traditional shared networking
topology, where the connected nodes contend for the same network
bandwidth. When two switching nodes are communicating, they are
connected with a dedicated channel between them, so there is no contention
for network bandwidth with other nodes. As a result, the switch reduces
considerably the likelihood of traffic congestion.
For Fast Ethernet networks, a switch is an effective way of eliminating the
problem of chaining hubs beyond the “two-repeater limit.” A switch can be
used to split parts of the network into different collision domains, 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 the existing 10Mbps networks and the new 100Mbps
networks.
Switching LAN technology is a marked improvement over the previous
generation of network hubs and bridges, which were characterized by higher

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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.
Features
The DES-1024D is a high-performance switch designed specifically for
environments where traffic on the network and the number of users increase
continuously.
924-port 10/100BASE Ethernet Switch with RJ-45 connectors
9Supports Auto-negotiation of speed and duplex modes for each
port
9Supports Auto-MDI/MDI-X on each port, eliminating the need for
cross over cables or uplink ports
9Wire-speed reception and transmission
9Store-and-Forward switching method
9Integrated address Look-Up Engine, supports 8K MAC addresses
9Supports 1.25 Mbits RAM for data buffering
9Front-panel diagnostic LEDs
9IEEE 802.3x flow control for full-duplex
9Back pressure flow control for half-duplex
9IEEE 802.1p Priority support
IEEE802.1P AND QOS
The DES-1024D Switches support 802.1p priority queuing Quality of Service.

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The implementation of QoS (Quality of Service) and benefits of using 802.1p
priority queuing are described here.
Advantages of QoS
QoS is an implementation of the IEEE 802.1p standard that allows network
administrators a method of reserving bandwidth for important functions that
require a large bandwidth or have a high priority, such as VoIP (voice-over
Internet Protocol), web browsing applications, file server applications or
video conferencing. Not only can a larger bandwidth be created, but other
less critical traffic can be limited, so bandwidth can be saved. The Switch
has separate hardware queues on every physical port to which
packets from various applications are mapped to and assigned a
priority. The illustration below shows how 802.1P priority queuing
is implemented on the Switch. The eight IEEE 802.1P priority
levels defined by the standard are mapped to the two class queues
used in the Switch.
2 Priority Queues
Queues:
Priority:
Class-0
0
Class-1
14 72 3 5 6

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Mapping QoS on the Switch
The picture above shows the default priority setting for the Switch. Class-1
has higher priority than Class-0 on the Switch. In order to implement QoS,
the user is required to instruct the Switch to examine the header of a packet to
see if it has the proper identifying tag tagged. Then the user may forward
these tagged packets to designated queues on the Switch where they will be
emptied, based on priority.
"The DUT support strict mode for 802.1p QoS. The untagged pkt will follow
the priority 0 to work (i.e. class 0)."
Understanding QoS
The Switch has two priority queues labeled 1 (higher queue), and 0 (lower
queue). The eight priority tags, specified in IEEE 802.1p are mapped to the
Switch's priority tags as follows:
Priority 0 is assigned to the Switch's Q0 queue.
Priority 1 is assigned to the Switch's Q0 queue.
Priority 2 is assigned to the Switch's Q0 queue.
Priority 3 is assigned to the Switch's Q0 queue.
Priority 4 is assigned to the Switch's Q1 queue.
Priority 5 is assigned to the Switch's Q1 queue.
Priority 6 is assigned to the Switch's Q1 queue.
Priority 7 is assigned to the Switch's Q1 queue.
The Switch uses strict priority for Scheduling. Strict priority-based
scheduling, any packets residing in the higher priority queues are transmitted

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first.
UNPACKING AND SETUP
Unpacking
Open the shipping cartons of the DES-1024D and carefully unpack its
contents. The carton should contain the following items:
9One DES-1024D 24-port 10/100Mbps Fast Ethernet Switch
9One AC power cord
9Four rubber feet to be used for shock cushioning
9Screws and two mounting brackets
9Quick Installation Guide
9Manual
If any item is found missing or damaged, please contact your local reseller
for replacement.
Setup
The setup of the DES-1024D can be performed by using the following steps:
1. The surface must support at least 11 lbs (5 kg).
2. The power outlet should be within 6 feet (1.42 meters) of the
device.
3. Visually inspect the power cord and see that it is secured fully
to the AC power outlet.
4. Make sure that there is adequate ventilation around the
Switch.
5. Do not place heavy objects on the Switch.

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Desktop Installation
When installing the DES-1024D on a desktop or shelf, the rubber feet
included with the device should be attached first, to minimize scratching or
scarring of the surface on which the Switch is placed. Attach these
cushioning feet on the bottom at each corner of the device. Allow enough
ventilation space between the device and the objects around it.
Fast Ethernet Switch installed on a Desktop or Shelf
Rack Mounting
The DES-1024D can be mounted in an EIA standard-size 19-inch rack, in a
wiring closet with other equipment. Attach the mounting brackets on each
side of the Switch’s front panel (as shown in the illustration below), and
secure them with the screws provided.