GarrettCom 4K-Series User manual

www GarrettCom com .. www GarrettCom com ..
Corporate Headquarters :
GarrettCom, Inc.
213 Hammond Avenue
Fremont, CA 94539
Phone: [phone]
Fax: [phone]
Web: http://www.GarrettCom.com
Email: [email protected]
Magnum 4K-Series
4K8 Switches
Installation and User Guide
$5.00 USD

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Magnum
 4K-Series
4K8 Switches
Installation and User Guide
Part #: 84-000080 Rev. D
Trademarks
Ethernet is a trademark of Xerox Corporation
NEBS is a trademark of Telcordia Technologies
UL is a registered trademark of Underwriters Laboratories
GarrettCom, Magnum and Personal Switch are trademarks and Personal Hub is a
registered trademark of GarrettCom, Inc.
Important: Magnum 4K-Series Fiber Switches contain no user serviceable
parts. Attempted service by unauthorized personnel shall render any and all
warranties null and void. If problems are experienced with a Magnum 4K8
Switches, consult Section 6, Troubleshooting, of this User Guide.
Copyright 2004 GarrettCom, Inc. All rights reserved. No part of this publication may
be reproduced without prior written permission from GarrettCom, Inc.
Printed in the United States of America.

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Contacting GarrettCom, Inc.
Please use the following mailing address, phone and fax numbers or Internet address.
GarrettCom, Inc.
47823 Westinghouse Drive
Fremont, CA 94539
Phone: [phone]
Fax: [phone]
Web: http://www.GarrettCom.com
Email: [email protected]om
Federal Communications Commission
Radio Frequency Interference Statement
Warning: Changes or modifications to this unit not expressly approved by the party
responsible for compliance could void the user’s authority to operate the equipment.
NOTE: This equipment has been tested and found to comply with the limits for a class
B digital device, pursuant to part 15 of the FCC Rules. These limits are designed to
provide reasonable protection against harmful interference in a residential
installation. This equipment generates, uses, and can radiate radio frequency energy
and, if not installed and used in accordance with the instructions, may cause harmful
interference in a residential installation. This equipment generates, uses, and can
radiate frequency energy and, if not installed and used in accordance with the
instructions, may cause harmful interfernce to radio communications. However, there
is no guarantee that interference to radio communications. However, there is no
guarantee that interference will not occur in a particular installation. If this equipment
does cause harmful interference to radio or television reception, which can be
determined by turning the equipment off and on, the user is encouraged to try to
correct the interference by one or more of the following measures.
- Reorient or relocate the receiving antenna.
- Increase the separation between the equipment and receiver.
- Connect the equipment into n outlet on a ccircuit different from that ot
which the receiver is connected.
- Consult the dealer or an experienced radio TV technician for help.
Canadian Emission
This Class B digital apparatus meets all requirements of the Canadian Interference-
Causing Equipment Regulations.
Cet appareil respecte toutes les exigences du R é glement sur le mat é riel du
Canada. Cet appareil est Classe B.

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TABLE OF CONTENTS Page
1.0 SPECIFICATIONS ............................................................................... 1
1.1 Technical Specifications...................................................................... 1
1.2 Ordering Information........................................................................... 3
2.0 INTRODUCTION ................................................................................. 4
2.1 Inspecting the Package and Product .................................................... 4
2.2 Product Description - Magnum 4K8 Switches .................................... 5
2.2.1 Magnum 4K8 Switch chassis.............................................................. 5
2.2.2: Magnum 4K8R “Reverse” model, front LEDs and connections in
rear............................................................................................................... 6
2.2.3 Fiber-port modules, 100Mb fiber....................................................... 7
2.2.4 Fiber-port modules, 10 Mb fiber........................................................ 8
2.2.5 10/100 Dual-speed Switched ports, RJ-45 (copper) .................... 8
2.2.6 Frame Buffering and Latency...................................................... 9
2.3 Features and Benefits......................................................................... 11
2.4 Applications....................................................................................... 12
3.0 INSTALLATION: ..................................................................................... 14
3.1 Locating Magnum 4K8 Switches....................................................... 14
3.2 Connecting Ethernet Media ............................................................... 15
3.2.1 Connecting Fiber Optic ST-type, “twist-lock”.......................... 15
3.2.2 Connecting Fiber Optic SC-type, "Snap-In".............................. 16
3.2.3 Connecting Single-Mode Fiber Optic........................................ 16
3.2.4 Connecting Twisted Pair (RJ-45,CAT3, CAT5......................... 16
3.3 Rack-mounting ................................................................................... 17
3.4 Fiber Port Module (FPM) Installation ............................................... 18
3.4.1 Preparation for Installing and Removing FPMs......................... 18
3.4.2 Installing FPM Cards in the Magnum 4K8 Switches................. 20
3.5 Powering the Magnum 4K8 Switch................................................... 22
4.0 OPERATION....................................................................................... 23
4.1 Switching Functionality..................................................................... 23
4.2 Status LEDs ....................................................................................... 24
4.3 Manual Switches for Up-link push-button, for RJ-45 Port#1 only.... 24
4.4 Manual Switches “F-H”, for FPM Port#9 only.................................. 24
4.5 Auto-negotiation, for Fast Ethernet copper ports............................... 24
4.6 Auto-negotiation for 10/100Mb ports,............................................... 26
4.7 Flow-control, IEEE 802.3x standard ................................................. 26
4.8 Power Budget Calculations for 4K-Series FPM’s with Fiber Media. 27
5.0 INTRO - MAGNUM 4K8 FIBER-PORT MODULES (FPM)......... 28
5.1 Inspecting the Package and Product (Optional)................................. 28
5.2 Product Description ........................................................................... 28
5.2.1 FPM-MST,100Mbps multi-mode FX-ST-type, “twist-lock”..... 29
5.2.1a FPM10-MST,10 Mbps multi-mode FL-ST-type, “twist-lock” .. 29
5.2.2 FPM-MSC100Mbps multi-mode FX-SC-type, “snap-in” ......... 29
5.2.3 FPM-SSC 100Mbps single-mode FX-SC-type, “snap-in”......... 30

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5.2.4 FPM-MTRJ,100Mb multi-mode FX, MTRJ small-form-factor 30
5.2.5 FPM-MV45, 100Mbps multi-mode FX, VF-45 small-form-factor 31
5.2.6 FPM-Blank................................................................................. 31
6.0 TROUBLESHOOTING...................................................................... 32
6.1 Before Calling for Assistance............................................................ 32
6.2 When Calling for Assistance ............................................................. 33
6.3 Return Material Authorization (RMA) Procedure............................. 33
6.4 Shipping and Packaging Information................................................. 34
APPENDIX A: WARRANTY INFORMATION......................................... 34
APPENDIX B : INTERNAL DC POWER SUPPLY OPTIONS ................ 35
APPENDIX C: INTERNAL DC DUAL-SOURCE POWER OPTION...... 37
Revisions
10/04: minor updates
04/03: Edited Minor change
Rev D 06/02 : Updated Rack-mounting and Appendix B & C with 24VDC and
125VDC Power option.
Rev C 01/02 : Updated Operating Environment Spec.
Rev B 04/01 : Change the company name to GarrettCom, Inc. (Formerly it was
Garrett Communications). There are no changes to the content of the material at
this time
Rev A 12/00 : This revision is the initial release of the 4K8 Switches user
manual.
.

Magnum Quad-Series Fiber Switches Installation and User Guide (10/04)
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The Magnum Line
ETHERNET CONNECTIVITY PRODUCTS
"DESIGNED AND MANUFACTURED IN THE USA"
OVERVIEW
GarrettCom, Inc offers the premium-quality Magnumline of Ethernet LAN
connectivity products with industry-standard functionality and built-in fiber
configurability. Magnum products are designed for use in demanding Carrier Class,
Industrial Grade and OEM applications where reliability is a primary consideration.
6K25 Managed Fiber Switches, Gigabit, 100 and 10 Mbps, fiber and copper ports,
mix-and match. Features SFF fiber for up to 25 fiber ports in a 1U unit.
4K-Series Switches, 100 and 10 Mbps, copper ports with optional fiber port, with
auto-negotiating full switching performance.
Quad-Series Fiber Switches, 100 & 10Mbps, fiber and copper ports, mixed-speed
and mixed-media types, full switching performance.
“Outdoor” Ethernet Switch, for temperature uncontrolled locations
6 10/100 and 2 100Mb fiber ports, can be connected in strings
Mixed-Media Fiber Hub, 16-port Stackable,10/100 auto-sensing
Dual Speed 8-port and 16-port Stackables, 10/100 auto-sensing
Stackable Hubs, SNMP Optional
10Mb series and 100Mb series, both w/ optional port modules
Personal Switches, 10/100Mb
8 port dual speed, Auto-negotiable with fiber option
Personal Hubs, 100Mb or 10/100Mb
8-port, with two switched ports (1 fiber built in)
Personal Hubs, 10Mb series
8-port + AUI, stackable to 5 high, + optional BNC of fiber port
8 or 9-port and 4 or 5-Port Personal Hubs, w/ man. up-link sw.
Media Converters, 10Mb and 100Mb series
All media combinations, incl. fiber ST, SC, mm., single mode
The “X-line” of configurable MiXed Media products:
Stackable Concentrators, SNMP optional, 13-Ports
Mini-Concentrators, 7 Ports, Repeaters, 2-Ports
Repeater Port Modules (RPMs),6 types for Ethernet media
Bridge Port Modules (BPMs), 4 types, for segment isolation
Transceivers, 10Mb series Mini-Transceivers and Coax Models Oct, 04

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1.0 SPECIFICATIONS
1.1 Technical Specifications
Performance
Aggregate Filtering Rate: (all ports are wire speed)
1,190,400 frames/sec for 8 100Mbps ports (for Magnum 4K8)
Aggregate Forwarding Rate: (all ports are wire speed)
595,200 frames per second
Data Rate: 10 Mbps and 100Mbps
Address Table Capacity:16K node addresses,self-learning w/address aging
Packet buffer size : 1 MB dynamic
Latency: 5 s + packet time (100 to 100Mbps)
15 s + packet time (10 to 10 Mbps, and 10 to 100Mbps)
Network Standards
Ethernet V1.0/V2.0 IEEE 802.3: 10BASE-T,
IEEE 802.3u: 100BASE-TX, 100BASE-FX
Maximum 10 Mbps Ethernet Segment Lengths
Unshielded twisted pair - 100 m (328 ft)
Shielded twisted pair - 150 m (492 ft)
10BASE-FL multi-mode fiber optic - 2 km (6,562 ft)
10BASE-FL single-mode fiber optic - 10 km (32,810 ft)
Maximum Standard Fast Ethernet Segment Lengths:
10BASE-T (CAT 3, 4, 5 UTP) - 100 m (328 ft)
100BASE-TX (CAT 5 UTP) - 100 m (328 ft)
Shielded twisted pair - 150 m (492 ft) 100BASE-
FX, half-duplex, multi-mode - 412 m (1350 ft) 100BASE-
FX, full-duplex, multi-mode - 2.0 km (6,562 ft)
100BASE-SX, short wavelength HDX m.m. - 300 m ( 935 ft)
100BASE-FX, half-duplex, single-mode - 412 m (1350 ft)
100BASE-FX, full-duplex, single-mode - 20.0 km (49,215 ft)
100BASE-FX, full-duplex, s.m(Long Reach)- 40.0 km (132,215 ft)
Connectors for copper wiring
Twisted Pair at 10/100Mb:RJ-45 shielded, female, front mounted
(for Magnum K-Series Fast Ethernet copper ports, use Cat 5 cable)
Fiber Multi-mode connector types:
Fiber Port, SC-type (snap-in): Fiber optic multi-mode, 100BASE-FX
Fiber Port, ST-type (twist-lock): Fiber optic multi-mode, 100BASE-FX
Fiber Port, MTRJ-type (plug-in): Fiber optic multi-mode, 100BASE-FX
Fiber Port, VF-45 type (plug-in): Fiber optic multi-mode, 100BASE-FX
Fiber Port, ST-type (twist-lock):Fiber optic multi-mode, 10BASE-FL
Fiber Single-mode connector types:
Fiber Port, SC-type: Fiber optic single-mode, 100BASE-FX
Manual switch-selections and jumpers
Up-link Push-button: Crossover switch for one RJ-45 port#1
F-H: In F Port #9(fiber port)at full 100Mbps and in H at Half-duplex
Fiber default: Full-duplex (Internal jumpers may select HDX mode)
Copper default: Auto-negotiation

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LEDs: Per Port
LK/Act: Steady ON for Link with no traffic, blinking indicates
port is transmitting and receiving
F/H: ON = Full-Duplex Mode
OFF = Half-Duplex Mode
100/10: ON = 100Mbps speed
OFF = 10 Mbps
Operating Environment
Ambient Temperature: 25to 140F (-5to 60C)
Storage Temperature: 0to 185F (-40to 85C)
Ambient Relative Humidity: 5% to 95% (non-condensing)
Altitude: -200 to 13,000ft (-60 to 4000m)
Conformal coating options: Request quote
Packaging
Enclosure: Rugged High strength metal. Suitable for stand-
alone or rack-mounting
Dimensions: 1.75 in H x 17.0 in W x 9.0 in D
4.45cm H x 43.2cm W x 22.9cm D
Weight: 3.2 lb. (1.4 Kg) rack-mount models
Cooling method: Fan cooled, @ 9 cfm
Power Supply (Internal)
AC Power Connector: IEC-type, male recessed at rear of chassis, with
adjacent manual ON-OFF switch (on AC models only)
Input Voltage: 110 to 240 VAC (auto-ranging)
Input Frequency: 47 to 63 Hz (auto-ranging)
Power Consumption: 9 watts typical, 11 watts max.
Power Supply Rating: 3Amps at 5VDC
DC Power Supply (Options)
-48VDC Power Input Voltage : 36 to 72 VDC
24VDC Power Input Voltage : 20 to 36VDC
125VDC Power Input Voltage : 120 to 160VDC
Std. Terminal Block : “ -, GND, + ”
Power Consumption: same as for AC models, see above
For Dual Source and Redundant DC for –48VDC, 24VDC &
125VDC supply options (Optional), see Appendices
Mechanical
Enclosure : Rugged high strength sheet metal. Suitable for stand-alone or
1U rack mounting.
Rack-mounting brackets: 19” included; ETSI and 23” Telco optional.
Agency Approvals
UL listed (UL1950), cUL, CE
Emissions meet FCC Part 15 Class B
Optional: ETSI and NEBS L3 Certified
Warranty Three years, return to factory Made in USA

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1.2 Ordering Information
Magnum 4K8 Switches
MODEL DESCRIPTION
Magnum 4K8 Ethernet Switch with 8 RJ-45 ports, each auto-sensing for
10Mbps/10Mbps FDX/HDX operation. Optional fiber port
may be configured from the family of modules below.
Each port is switched and provides a full-speed traffic
domain with non-blocking performance. Includes internal
auto-ranging power supply, cooling fan, and metal brackets
for rack-mounting. LEDs and user ports are in the front,
power inputs is in the rear. Units with -48V power supply
options available
Magnum 4K8R “Reverse” model, Same as Model 4K8 Switch except user
ports and the power input connectors are in the rear.
Fiber Port Modules for Magnum 4K-Series(4K8 Switches only)
FPM-MSC Fiber module for 4K8 Switches, with 100Mbps multi-mode
FX SC connectors
FPM-MST Fiber module for 4K8 Switches, with 100Mbps multi-
mode FX ST connectors
FPM-SSC Fiber module for 4K8 Switches, with 100Mbps single-
mode FX SC connectors
FPM-MV45 Fiber module for 4K8 Switches, with 100Mbps multi-
mode FX “VF-45” connectors
FPM-MTRJ Fiber module for 4K8 Switches, with 100Mbps multi-
mode FX “MTRJ” connectors
K8PM-RJ45 RJ-45 module for 4K8 Switches, with 100Mbps fixed RJ-
45 ports, full or half-duplex
FPM10-MST Fiber module for 4K8 Switches, with 10 Mbps multi-mode
FL ST-type connectors
FPM-BLNK Blank face plate, included in 4K8 switch unit when no fiber
port option is selected
See appendices B and C for information on DC-powered models and options.
GarrettCom, Inc. reserves the right to change specifications, performance
characteristics and/or model offerings without notice.

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2.0 Introduction
2.1 Inspecting the Package and Product
Examine the shipping container for obvious damage prior to installing this
product; notify the carrier of any damage that you believe occurred during shipment or
delivery. Inspect the contents of this package for any signs of damage and ensure that
the items listed below are included.
This package should contain:
1 Magnum 4K8 Switches
1 AC Power Cord (U.S. and other 115 VAC only)
1 Set of metal “Ears” for rack mounting
1 Installation and User Guide (this manual)
1 Product Registration Card
Remove the items from the shipping container. Be sure to keep the shipping
container should you need to re-ship the unit at a later date. To validate the product
warranty, please complete and return the enclosed Product Registration Card to
GarrettCom, Inc as soon as possible.
In the event there are items missing or damaged, contact the party from whom
you purchased the product. If the unit needs to be returned, please use the original
shipping container if possible. Refer to Section 6, Troubleshooting, for specific return
procedures.

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2.2 Product Description - Magnum 4K8 Switches
Magnum 4K8 Switches boost the performance of Ethernet LANs, and have the
flexibility of both twisted-pair switched ports and a fiber port. The optional fiber port
considered as the additional 9
th
port, may be configured from a variety of user selected
popular fiber connector. The 8 dual speed RJ-45 ports are 10/100 Mb and support auto-
negotiating.
The Magnum 4K8 Switches provide the switching speed and the reliability to
smoothly support multiple workgroups at 100Mbps or 10 Mbps speed. The optional
“future-proof” fiber port is normally 100Mbps speed with factory default setting to
operate in full-duplex mode. Alternatively, for 10Mbps fiber, a multi-mode half-duplex
ST-type port option is available. The optional fiber port is normally configured and
tested with the Magnum 4K8 unit in the factory, but may be configured in the field
Designed for use in departments with multiple workgroups, in remote offices
and in network traffic centers or multi-system power users, the Magnum 4K8 Switches
are easy to install and use. Addresses of attached nodes are automatically learned and
maintained, adapting the switching services to network changes and expansions. Front-
mounted LEDs provide status information on each port. The Magnum 4K8 Switches
provide high performance plug-and-play operation in convenient rack-mount packages.
The Magnum 4K8 switches are non-blocking on all ports and include 1MB
packet buffers and 16K-node address table for advanced performance. The Magnum 4K8
Switches, with store-and-forward switching, filter all faulty packets to minimize traffic
congestion.
2.2.1 Magnum 4K8 Switch chassis
Magnum 4K8 Switches come in chassis size of an 8-port rack-mount.
The rack-mount units are typically used in larger network wiring centers.
The optional fiber port is user configurable and can be selected from the offered popular
fiber port connectors. The fiber-port modules are normally factory installed, but may be
changed or added in the field. (See Section 5).
The 4K8 19” rack-mountable Switches comes along with eight 10/100 RJ-45
ports and one optional 10 or 100Mbps fiber port module on the right, i.e., with a capacity
of 9 switched ports.

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Figure 2.2.1a: Front view, 8-
port Magnum 4K8 Switches
All port, LED’ connector and manual switches are located on the front panel
of Magnum 4K8 Switches. There are power(PWR) and error(Error) indicators for the
unit. There are Link and Activity(Link/Act) indicators for each 10Mbps and 100Mbps
domain, for visual indication of the operating status of each domain, and there are Soeed
and F/H Full and Half duplex Leds for each port. The manual switch with (=, x)supports
the port#1 for crossover port feature, whereas “F-H” manual switch for FPM port are
user selectable for full fixed and half duplex. The IEC standard AC power connector (and
a manual ON - OFF power switch) located at the rear. Fan-driven cooling air flows left
to right.
Figure 2.2.1b: Rear view - Magnum
table-top & rack-mount 4K8 Switch
2.2.2: Magnum 4K8R “Reverse” model, front LEDs and connections in
rear
Rear View
Front View
The Magnum 4K8R is like the 4K8F except that the front panel has the
LEDs, and all the connecting ports and power feeds are in the back. This is convenient
for rack-mounting where cabling is accessed from the rear of the rack while the operating
status LEDs are monitored from the front. Typically such arrangements are found in
Telco rack installations.
1 2 3 4 5 6 7 8
A L
POWER
ERROR L/A
SPEED
F/H
MAGNUM 4K-Series
Ethernet 10/100 Switch
UPLINK
= X
FH
ON
OFF
110-220
VAC
47-63Hz
1.0-0.5A
1 2 3 4 5 6 7 8
A L
POWER
ERROR L/A
SPEED
F/H
UPLINK
= X
F
H
(-) GND (+)
48V DC
ON
OFF
FH
1 2 3 4 5 6 7 8
POWER
ERROR L/A
SPEED
F/H
MAGNUM 4K8
Ethernet 10/100 Switch

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The Magnum 4K8R is dual-speed 10/100Mbps switch and has a fiber
connector port options. The switching capability allow the Magnum 4K8R to support
multiple workgroup smoothly with its own switched 100Mbps or 10Mbps domain.
Normally the 4K8R is equipped with an optional internal 48VDC power
supply (See Appendix A). There is an additional option of a dual-source 48V input (See
Appendix B).
The DC power feed options and the high quality and versatility make the Magnum 4K8R
a good high-availability choice for Telcos, ISPs, broadcast equipment, medical,
brokerage firm, financial facilities and Industrial Environment.
2.2.3 Fiber-port modules, 100Mb fiber
Fig.2.2.3 Fiber-Port Modules, FPM-ST, FPM-SC, FPM-MTRJ
The fiber port module is optional for Magnum 4K8 Switch. In a fiber port
module, all of the fiber ports are of the fixed speed at 100Mbps or 10Mb, either multi-
or single-mode, and different connector type. Multi-mode 100Mbps models are available
with ST, SC, and MTRJ connections. Single-mode 100Mbps models are available with
SC connectors.
The 100Mb fiber port modules on the Magnum 4K8 normally are set (factory
default) to operate in full-duplex mode for best fiber distance and performance. On the
Magnum 4K8, the user may select full- or half-duplex mode per-port with an internal
jumper setting (See Section 3.4) for the flexibility to adapt to any type of Fast Ethernet
devices.
On Magnum FPMs, there are two LED’s per fiber port. The Link (LK) LED
indicates “ready for operation” when lit), and an LED indicates Receiving Activity
A L A L
A

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(ACT) on the port. A fiber cable must be connected to each 100Mb port and a proper link
LK lit) must be made with the device at the other end of the cable in order for the LK
LEDs to provide valid indications of operating conditions.
2.2.4 Fiber-port modules, 10 Mb fiber
The 10Mb model FPM10-MST fiber port module is the
same as the 100Mb FPM-MST, except for 10 Mb speed rather
than 100Mb speed. It supports distances according to the
10Base-FL standard, i.e., 2Km distance for multi-mode fiber.
(Single-mode for 10km distance may be available as a special
order).
2.2.5 10/100 Dual-speed Switched ports, RJ-45 (copper)
The Magnum 4K8 copper has 8 port dual speed 10/100Mb switched. RJ-45
ports. The 10/100Mb switched ports are independently N-way auto-negotiating (as a
default setting),
for operation at 10 or 100Mb
speed in full- or half-duplex mode. They independently move to half-duplex mode at 10
Mb or at 100Mb speed if the device at the other end of the twisted pair cable is half-
duplex or is not an auto-negotiating device.
There are three LED’s for each port. The LK/Act (Link/Activity) steady ON
for Link with no traffic and blinking indicates port is receiving and transmitting. The
Speed LED indicates operation at 100Mb speed when ON and at 10 Mb speed when OFF
(when auto-negotiation is not disabled). The F/H LED is ON to indicate full-duplex
operation and OFF to indicate half-duplex mode. A twisted pair cable must be connected
into each RJ-45 10/100Mb port and a proper Link (LK lit) must be made with the device
at the other end of the cable in order for the LEDs to provide valid indications of
operating conditions.
The port#1 is equipped with a Media Dependent Interface-Crossover (MDI-
X) push-button switch to simplify cascaded or up-link connections.
A L
1 2 3 4 5 6 7 8
POWER
ERROR L/A
SPEED
F/H
UPLINK
= X

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2.2.6 Frame Buffering and Latency
The Magnum 4K8 are store-and-forward switches. Each frame (or packet) is
loaded into the Switch’s memory and inspected before forwarding can occur. This
technique ensures that all forwarded frames are of a valid length and have the correct
CRC, i.e., are good packets. This eliminates the propagation of bad packets, enabling all
of the available bandwidth to be used for valid information.
While other switching technologies such as "cut-through" or "express" impose
minimal frame latency, they will also permit bad frames to propagate out to the Ethernet
segments connected. The "cut-through" technique permits collision fragment frames,
which are a result of late collisions, to be forwarded to add to the network traffic. Since
there is no way to filter frames with a bad CRC (the entire frame must be present in order
for CRC to be calculated), the result of indiscriminate cut-through forwarding is greater
traffic congestion, especially at peak activity. Since collisions and bad packets are more
likely when traffic is heavy, the result of store-and-forward operation is that more
bandwidth is available for good packets when the traffic load is greatest.
To minimize the possibility of dropping frames on congested ports, each
Magnum 4K8 Switches dynamically allocates buffer space from an 1MB memory pool,
ensuring that heavily used ports receive very large buffer space for packet storage.
(Many other switches have their packet buffer storage space divided evenly across all
ports, resulting in a small, fixed number of packets to be stored per port. When the port
buffer fills up, dropped packets result.) This dynamic buffer allocation provides the
capability for the maximum resources of the Magnum 4K8 unit to be applied to all traffic
loads, even when the traffic activity is unbalanced across the ports. Since the traffic on
an operating network is constantly varying in packet density per port and in aggregate
density, the Magnum 4K8 Switches are constantly adapting internally to provide
maximum network performance with the least dropped packets.
When the Switch detects that its free buffer queue space is low, the Switch
sends industry standard (full-duplex only) PAUSE packets out to the devices sending
packets to cause “flow control”. This tells the sending devices to temporarily stop
sending traffic, which allows a traffic catch-up to occur without dropping packets. Then,
normal packet buffering and processing resumes. This flow-control sequence occurs in a
small fraction of a second and is transparent to an observer. See Section 4.6 for
additional details.

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Another feature implemented in Magnum 4K8 Switches is a collision-based
flow-control mechanism (when operating at half-duplex only). When the Switch detects
that its free buffer queue space is low, the Switch prevents more frames from entering by
forcing a collision signal on all receiving half-duplex ports in order to stop incoming
traffic.
The latency (the time the frame spends in the Switch before it is sent along or
forwarded to its destination) of the 4K8 Switches varies with the port-speed types, and
the length of the frame is a variable here as it is with all store-and-forward switches. For
10 Mb-to-10 Mb or 10 Mb-to-100Mb or 100Mb-to-10 Mb forwarding, the latency is 15
microseconds plus the packet time at 10 Mb. For 100Mb-to-100Mb forwarding, the
latency is 5 microseconds plus the packet time at 100Mb.

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2.3 Features and Benefits
100Mb switching services for large, high performance Ethernet LANs
Magnum 4K8 Switches provide Fast Ethernet switching on all ports.
They perform high speed filter/forward operations on the traffic, giving
each port’s segment a full 100Mb (or 10 Mb) of bandwidth.
Option to configure a fiber port (port 9), all fiber connector types
Fiber port modules are available with 100Mb mm ST, SC, VF-45, MTRJ
single-mode SC, and 10 Mb ST-type connectors. The configuration of the
fiber port, in the factory or in the field, allows the 4K8 Switches to adapt
to mixed and changing fiber types in any application.
Manual Switch “F-H” for user configurable
The Manual switch “F-H” allows the user to setup port#9(fiber port) as
per their convenience to 100Mbps full-duplex at “F” and half- duplex at
“H” mode by sliding the manual switch under the FPM Port.
Eight RJ-45 (copper) ports, 10/100 auto-negotiation
RJ-45 ports provide twisted pair segment connections, with N-way auto-
negotiation per port and full and half manual settings for optional port.
Full-duplex or Half-duplex operation, auto-sensing
All fiber and RJ-45 (copper) ports are capable of half- or full-duplex,
individually selected. All RJ-45 ports support 10/100 auto-negotiation.
Rack-mounting may be std or “reverse”,19 inch, ETSI or 23” Telco
The standard rack mounting provides Ethernet ports and status LEDs in
front, service connections (power input and Ethernet cables) in the rear.
“Reverse” rack mounting provides status LEDs in front and all cabling
connections in the rear. Standard 19’ rack mount brackets are included,
while ETSI and 23” Telco are optional.
Plug-and-Play installation for high performance switching
Magnum 4K8 Switches are self-learning for node addresses. They
can be placed into operation without complex set-up procedures,
even in large networks. They operate transparent to system software.
Standard AC power input, -48VDC, 24VDC, or 125VDC is available
Standard AC power input is IEC plug, auto-ranging for worldwide use. For
special applications, models with –48VDC, 24VDC, or 125VDC are
available. Dual source DC input can also be selected and configured on the
–48VDC, 24VDC, and 125VDC input models.
Extended Temperature Operation
The Magnum 4K8 has been tested for operation at temperatures of –5’C to
55’C. NEBS-certified models have been tested to a greater range per
NEBS Level 3 requirements. For details, email m[email protected]

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2.4 Applications
Magnum 4K8 Switches offer high performance and flexibility, and are easily
used in a variety of applications including client/server computing, performance
upgrades of departmental networks, and collapsed backbone applications. The Dual-
Speed characteristic of the 4K8 Switches enables them to inter-connect a series of
subnets (one subnet per 4K-Series Switch) in a LAN traffic center. The subnet
connections may be via either optional fiber or twisted pair cabling, and may be
100Mbps or 10 Mbps speed and full-or half-duplex mode.
The mixed-media capability is ideal for upgrading existing Ethernet LAN
networks, where existing cabling must be accommodated. The fiber-built-in media
capability is ideal for integrating future-proof fiber cabling into the LAN structure.
Example1: In general application, a Switch is needed to provide a Fast Ethernet
backbone. The backbone consists of four high-speed LAN segments, each operating
over 100MB full-duplex fiber lines. In addition to interconnecting the fiber backbone
segments in the network center, the Switch needs to provide high-speed switched support
for two central servers, for a 100MB connection to a router, and for a dual-speed hub
serving a local workgroup of over a dozen users, printers, etc.
The Magnum 4K8 equipped with one optional Fiber port and eight RJ-45 ports
provides an economical solution, configured with 8 switched ports ( 10/100 RJ-45) in a
rack-mount box. No Media Converters are needed. The Fiber FPM can be selected to
provide any 100Mbps fiber media connector type desired. FPMs with multi-mode or
single-mode fiber types are available.
This requirement for connecting local devices over twisted pair cabling is
handled by the Magnum 4K8 with one optional Fiber-Port Module. The FPM provides a
switched port for distance with high bandwidth throughput to the connected network
away from the present network.
Since 100Mb fiber Ethernet has severe distance limitations at half-duplex, it is
necessary in high speed backbones to operate fiber links in the full-duplex mode. Many
low-end switches that only have RJ-45 N-way 10/100Mb ports would need to have a
media converter on each fiber line. But most media converters do not support auto-
negotiation and would not enable the fiber backbone lines to operate full-duplex. But the

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Magnum 4K8 . . . with optional switched fiber ports at 100Mb speed, with full-duplex
mode as a default setting on fiber ports, and with some RJ-45 N-way 10/100Mb ports as
well. . . handles this application readily.
Figure 2.4a: The Magnum 4K8 provides a 100Mb fiber backbone with high
bandwidth facility.
Example 2:
In another situation similar to Example 1 above, a central Switch is needed to
provide for a 8-segment 100Mb fiber Fast Ethernet backbone with switched copper
support for 1 high speed local servers and 5 personal network setup for each different
departments. In addition, the router and 1 port for future expansion.
The Magnum 4K8 switches fit nicely in this environment with future
backbone expansion. The 8 switched copper ports are handled with Magnum 4K8.
Should the number of servers expand, more than one server can be serviced by a
switched 4K8 port by using any of 10/100Mbps switched port.
Fig 2.4b: Magnum 4K8 provides a 100Mb backbone Switch.
100Mb Fiber Link
segment
1 2 3 4 5 6 7 8 9 10 11
12 13 14 15 16
X
UPLINK
LK/RX
PORT
100
1 2 3 4 5 6 7 8 9 10 11 12 1314 1516
PWR BR
COL 10
COL 100
Magnum DS8016 Stackable Hub
Magnum800E
Workgr oup Hub
100Mb /s
GARRETT
LINK
RX LINK RX
PWRCOL 1 2 3
45 6 7 8
100Mb Servers
100Mbps Workstations
Tx Rx
UPLINK
FH
= X
2SW
UPLINK 3 4 5 6 7 8
1SW
Magnum DS80F Dual Speed
Personal Hub
PORTS 1SW 2SW 3 4 5 6 7 8
Link/Act
Speed
F/H
Power
Error
GAR RET T
12V, 1.5Amps
1 2 3 4 5 6 7 8
A L
POWER
ERROR L/A
SPEED
F/H
MAGNUM 4K-Series
Ethernet 10/100 Switch UPLINK
= X
FH
Router

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3.0 Installation:
This section describes installation of the Magnum 4K8 Switches, as well as connection of
the various Ethernet media types.
Before installing the equipment, it is necessary to take the
following precautions:
1.) If the equipment is mounted in an enclosed or multiple rack
assembly, the environmental temperature around the equipment
must be less than or equal to 50
0
C.
2.) If the equipment is mounted in an enclosed or multiple rack
assembly, adequate air flow must be maintained for proper and
safe operation.
3.) If the equipment is mounted in an enclosed or multiple rack
system placement of the equipment must not overload or load
unevenly the rack system.
4.) If the equipment is mounted in an enclosed or multiple rack
assembly, verify the equipment’s power requirements to prevent
overloading of the building/s electrical circuits.
5.) If the equipment is mounted in an enclosed or multiple rack
assembly verify that the equipment has a reliable and
uncompromised earthing path.
6.) If the intra-building wiring (cabling) is involved with
this product(NEBS), then it is recommended to have shielded
cable and the shield is grounded at both ends.
3.1 Locating Magnum 4K8 Switches
The location of a Magnum 4K8 Switch is dependent on the physical layout of
the network. Typically the Switch is placed in a central wiring location where groups of
network devices need to be connected in order to communicate with each other. These
Switches are typically rack mounted in a wiring closet see Section 3.3.2 below), but
because they have rubber feet they can also be installed on a shelf or table top.
Locate an AC receptacle that is within six feet (2 meters) of the intended
Magnum 4K8 Switch site. The rugged metal case of the Magnum 4K8 Switch will
normally protect it from accidental damage in a lab or workplace setting. Maintain an
open view of the front to visually monitor the status LEDs. Keep an open area around
the sides of the unit so that cooling can occur from the small fan on the top of the main
switching chip, while the unit is in operation.