Magnum DS 880
10 / 100 Dual-Speed
Stackable Hubs
Installation and User Guide
www
.
GarrettCom
.
com
Magnum DS880 Dual-Speed Stackable Hubs
Installation and User Guide (05/01)
Contacting GarrettCom, Inc
Please use the mailing address, phone and fax numbers and email address listed below:
GarrettCom, Inc.
47823 Westinghouse Dr.
Fremont, CA 9453-7437
Phone (510) 438-9071
Fax (510) 438-9072
email [email protected]
Federal Communications Commission
Radio Frequency Interference Statement
This equipment generates, uses and can radiate frequency energy and if not
installed and used properly, that is in strict accordance with the manufacturer's
instructions, may cause interference to radio communication. It has been tested and
found to comply with the limits for a Class A computing device in accordance with the
specifications in Subpart J of Part 15 of FCC rules, which are designed to provide
reasonable protection against such interference when operated in a commercial
environment. Operation of this equipment in a residential area is likely to cause
interference, in which case the user at his own expense will be required to take whatever
measures may be required to correct the interference.
www
.
GarrettCom . com
ii
Magnum DS880 Dual-Speed Stackable Hubs
Installation and User Guide (05/01)
The Magnum Line
ETHERNET C ONNEC TIVITY PRODUC TS
"DESIG NED AND MANUFAC TURED 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.
4K-Series Switches, 100 & 10Mbps, 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
Fan-Outs, 10Mb series
2, 4 and 8 Port Models
Transceivers, 10Mb and 100Mb series 10Mb Mini-Transceivers
and Coax Models, All Types - Apr, 01
www
.
GarrettCom . com
iii
Installation and User Guide (05/01)
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............................................................................................ 5
2.2.1 Magnum DS880 Chassis ......................................................................... 7
2.2.2 10 / 100 Speed Auto-sensing................................................................... 7
2.3 Stacking Magnum DS880’s ............................................................................... 8
2.4 Bridge Module between the 10Mb and 100Mb Domains ................................... 9
2.5 Up-link Switch on Port # 8 for Cascading........................................................... 9
2.6 Features and Benefits........................................................................................ 10
2.7 Applications ...................................................................................................... 11
3.0 INSTALLATION ...................................................................................................... 13
3.1 Locating Magnum DS880 Dual-Speed Hubs.................................................... 13
3.1.1 Table-Top or Shelf Mounting................................................................ 13
3.1.2 Wall (or Vertical Surface) Mounting..................................................... 13
3.2 Connecting Ethernet Media............................................................................. 14
3.2.1 Connecting Twisted Pair (CAT3, CAT5).............................................. 14
3.2.2 Collision Domain Diameter, Cable Distances and PDV Calculations... 14
3.2.3 Connecting to NICs which support Auto-Negotiation........................... 17
3.3 Powering the Magnum DS880 .......................................................................... 18
4.0 OPERATION............................................................................................................. 18
4.1 Dual-Speed Functionality................................................................................ 18
4.1.1 Software Transparency........................................................................... 20
4.2 Port Speed settings for 10,100 and 10/100Mbps Mode only........................... 20
4.3 Auto-negotiation and speed-sensing ................................................................ 21
4.4 LEDs ................................................................................................................ 21
4.5 Up-link Switch.................................................................................................. 21
5.0 TROUBLESHOOTING............................................................................................. 22
5.1 Before Calling for Assistance ........................................................................... 22
5.2 When Calling for Assistance............................................................................. 23
5.3 Return Material Authorization (RMA) Procedure............................................. 23
5.4 Shipping and Packaging Information................................................................ 24
APPENDIX A: WARRANTY INFORMATION ................................................................ 24
APPENDIX B: OPTIONAL 48VDC POWER SUPPLY, ADDENDUM ........................... 25
Revisions
Rev C 05/01 : 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 B 02/99 : Added optional 48vdc power supply addendum; Port Speed settings for
10,100 and 10/100Mbps Mode only; Connecting to NICs which support Auto-
Negotiation information; and Collision Domain Diameter, Cable Distances and PDV
calculations.
Rev A 10/97 : This revision is the initial release of the DS880 Dual Speed
Stackable Hubs user manual.
www
.
GarrettCom . com
iv
Magnum DS880 Dual-speed Stackable Hubs
Installation and User Guide(05/01)
1.0
1.1
SPECIFICATIONS
Technical Specifications
100 or 10 Mb/s per port, auto-sensing for speed. DS880 hubs support
two traffic domains, one at 100Mb/s and one at 10Mb/s, have eight RJ-45
ports, and are stackable up to 3 units high operating as one repeater.
Performance
When a port is operating at 100Mb/s:
Data Rate: 100 Mb/s
PDV (Path Delay Value) : 80BT, exceeds Class II
When a port is operating at 10Mb/s:
Data Rate: 10 Mb/s
Partitioning: Enforced after 63 consecutive collisions
Auto-reconnect: Occurs after one packet of error-free reception
Network Standards
100Mb: Ethernet IEEE 802.3u , 100BASE-TX
10Mb: Ethernet IEEE 802.3, 10BASE-T
Auto-sensing for speed: IEEE 802.3u
Packet-Processing Between Domains (internal 10/100 switch or bridge)
Filtering and Forwarding Rate from 100Mb ports: 148,800 pps max
Filtering and Forwarding Rate from 10Mb ports: 14,880 pps max.
Processing type : Store and Forward
Auto-learning : 8K address table, shared for both traffic domains
Packet buffers : 2MB,dynamically allocated & shared on both domains
Latency (not including packet time) : 100 to 10Mb : 5µs
10 to 100Mb : 5µs
CPU Type : State Machine
Maximum Ethernet Segment (or Domain) Lengths
10BASE-T (Unshielded twisted pair)
- 100 m (328 ft)
100BASE-TX (CAT 5 UTP)
- 100 m (328 ft)
Operating Environment
Ambient Temperature:
Storage Temperature:
32ºF to 122ºF (0ºC to 50ºC)
-20ºC to 60ºC
Ambient Relative Humidity: 10% to 95% (non-condensing)
Power Supply (Internal
)
AC Power connector : IEC-type, male recessed, rear of chassis
Power Input Voltage : 90 to 260 VAC (auto ranging)
Power Input Frequency : 47-63 Hz
Power Consumption : 20 watts max
.
www
.
GarrettCom . com
1
Magnum DS880 Dual-Speed Stackable Hubs
Installation and User Guide (05/01)
(1.1 Technical Specifications, continued)
48VDC Power Supply (Optional
)
Power Input Voltage : 36 to 72 VDC (auto ranging)
Terminal Block in rear: “-, GND, +”
Power Consumption: 20 watts max.
Network Cable Connectors - for the eight RJ-45 shielded female ports per hub
100Mb: Category 5 UTP/STP
10Mb: Category 3, 4, 5 UTP (Note: speed-sensing does not sense cable type)
Stacking Cable - stacking may be up to four DS880 hubs, or 32 ports
A stacking cable with 50-pin “SCSI” male connectors, shielded, 9 inches (23 cm)
long, is included with each Magnum DS880-A Dual-Speed add-on unit.
Switch, Manual
UP-LINK : MDI-X thumb-operated slide switch, converts RJ-45 port #8 from a
regular (=position) user segment port to a crossover (X position) up-link port for
On/Off connection to a central hub or another cascaded hub. The up-link port #8
is auto-sensing for speed, and the up-link works the same at 10Mb or 100Mb.
Packaging
Enclosure: High strength metal. Metal mounting brackets included.
Suitable for wiring closet shelf, wall or desktop mounting.
Dimensions: 9.75 in D x 8.5 in. W x 1.4 in. H ( 25cm x 22cm x 3.5cm)
Weight: 2.5 lb. ( 1.15 Kg)
Cooling method: Fan cooled, internal @ 9 cfm
LED Indicators
PWR : Steady On when power applied
BR : Bridge Module Indicator, On when 10/100 bridge module is installed
(Model DS880-B), Off when no bridge module is inside (DS880-A)
COL : Collision LEDs, one each for 100Mb and 10Mb speed domains
ACT : Common packet activity indicator, one for each traffic domain
100 (per port): Steady On when speed is 100Mbps , Off when speed is 10Mb,
flashing when auto-negotiating or when not connected (no LINK)
LK (per port): Steady On when twisted-pair link is operational
RX (per port): Activity, flashing when port is receiving data
Agency Approvals
UL Listed (UL 1950), cUL, CE
Emissions: meets FCC Part 15, Class A
Optional: NEBS L3 Certified
Warranty
Three years, return to factory
GarrettCom com
Made in USA
www
.
.
2
Magnum DS880 Dual-Speed Stackable Hubs
1.2 Ordering Information
Installation and User Guide (05/01)
Magnum DS880 Dual-Speed Stackable Hubs
Magnum DS880-A:
Dual-Speed 10/100 Stackable Hub with eight RJ-45
ports, each auto-sensing for 100Mb or 10Mb operation. Stackable
up to three units high, with all ports in one stack operating as two
separate traffic domains, one domain at 100Mb/s and one domain
at 10Mb/s. Includes stacking cable, internal auto-ranging power-
supply, cooling fan, and metal brackets for shelf or wall mounting.
Magnum DS880-B:
Same as Magnum DS880-A but includes an internal
switch module that bridges the two traffic domains, filtering and
selectively forwarding packets between the 100Mb and the 10Mb
domains. Stacks up to three DS880-A units. One DS880-B unit per
stack supports all ports at 100Mb or 10Mb communicating with
each other. The internal switch has 2Mb dynamic store-and-
forward packet buffers and 8K node addresses.
GarrettCom reserves the right to change specifications, performance
characteristics and/or model offerings without notice.
www
.
GarrettCom . com
3
Magnum DS880 Dual-Speed Stackable Hubs
Installation and User Guide (05/01)
2.0
2.1
INTRODUCTION
Inspecting the Package and Product
Examine the shipping container for obvious damage prior to installing this product;
notify the carrier of any damage which 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
1
1
1
1
1
Magnum DS880-A or DS880-B Dual-Speed Hub Unit
AC Power Cord (U.S. and other 115 vac locations only)
Stacking Cable, Model DS880-A add-on (no bridge inside) units only
Set of metal clips and screws for wall-mounting
Installation and User Guide
Product Registration Card
Remove the Magnum DS880 Dual-Speed Hub from the shipping container. Be sure to
keep the shipping container should you need to 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 your supplier. If you need to
return the unit use the original shipping container. Refer to Chapter 5, Troubleshooting, for
specific return procedures.
www
.
GarrettCom . com
4
Magnum DS880 Dual-Speed Stackable Hubs
2.2 Product Description - General
Magnum DS880 Dual-Speed hubs have eight RJ-45 ports, each 10/100Mb auto-
Installation and User Guide (05/01)
sensing. Each port can independently identify (via IEEE 802.3u auto-sensing) and accept either
100Mb or 10Mb Ethernet signals, adapting to match the best speed of the connected device.
There are two internal traffic domains in Magnum DS880 hubs, one for the 100Mb traffic and
one for the 10Mb traffic. The 100Mb users share the 100Mb domain’s bandwidth and the 10Mb
users share the 10Mb domain’s bandwidth.
Any DS880 port can connect into either the 100 or the 10Mb traffic domain, and can
also change from one traffic domain to the other at any time without affecting the speed of other
ports. The automatic per-port speed-sensing is continuous, allowing the connected devices to
change speed at any time without impairing the operation of the other ports and connected
devices.
DS880A
10Mb Hub
100Mb Hub
1
2
3
4
5
6
7
8
PWR
BR
UPLINK
Magnum
1
2
3
4
5
6
7
8
1
2
3
4
5
6
7
8
9
10 11 12
1
2
3
4
5
6
7
8
9
1
0
1
1
1
2
PWR
Stackable
PWR
8000E
AC
T
LK
RX
Hub
GARRETT
C
OL
Figure 2.2.1 : Magnum DS880 is functionally both a 10Mb and a 100Mb hub in one
As Magnum DS880 Dual-Speed units are stacked, the two shared traffic domains
automatically expand to support all of the ports in the stack. Any combination of 10Mb and
100Mb ports, up to the maximum of 32 ports (4 units) in one stack, can be in use at any time.
One DS880 Model, the Magnum DS880-B, includes an internal bridge or switch
module which interconnects the 10 Mb and the 100Mb traffic domains. This enables all users on
a DS880-B hub or a DS880 stack, whether 100Mb or 10Mb, to talk to each other. The internal
switch of the DS880-B filters and selectively forwards packets between the 10Mb and the
100Mb domains, maintaining peak performance in each domain unaffected by local traffic in the
other domain. The internal bridge is self-learning, with large address table capacity for up to 8K
node addresses. As networked nodes are added or removed or move from one speed domain to
the other, the DS880’s internal switch automatically keeps track.
www
.
GarrettCom . com
5
Magnum DS880 Dual-Speed Stackable Hubs
Installation and User Guide (05/01)
2.2
Product Description - General (continued)
Bridge Module
DS880B
DS880A
1
2
3
4
5
6
7
8
PWR BR
1
UPLINK
2
8
3
4
5
6
7
AC
CO
T
LK
L
R
X
1
2
3
4
5
6
7
8
PWR
BR
UPLINK
1
2
3
4
5
6
7
8
AC
CO
T
LK
RX
L
Figure 2.2.2 : DS880B is a DS880A with a bridge module built-in for 10 to 100 bridging
Only one DS880-B unit is needed to support a stack. Additional 8-port units of the
DS880-A “add-on” hubs . . . units that do not have the bridge module inside, and which cost less
accordingly . . . can be added to the stack, up to the 4-unit stack maximum. In a stack, the
DS880-B unit (illustrated below as the bottom unit) can be in any stack position.
1
1
1
2
2
2
3
3
3
4
4
4
5
5
5
6
6
6
7
7
7
8
8
8
1
1
1
2
2
2
3
3
3
4
4
4
5
5
5
6
6
6
7
7
7
8
8
8
UPLINK
UPLINK
PWR BR
100
LK
RX
ACT
COL
A
A
A
100 10
PWR BR
100
LK
RX
ACT
COL
100 10
PWR BR
UPLINK
100
LK
RX
ACT
COL
100 10
1
2
3
4
5
6
7
8
1
2
3
4
5
6
7
8
PWR BR
UPLINK
100
LK
RX
ACT
COL
B
100 10
Figure 2.2.3 : Stack of DS880’s, 3 @ DS880A’s and 1 @ DS880-B
DS880-A units can also be used without a DS880-B, whereupon they will function as
dual-speed stackable hubs. This could be desired if there is an external non-auto-sensing switch
(such as the Magnum 300ES Two-Port Switch) available to interconnect the two speed domains,
or if only 100Mb devices are connected and the 10Mb domain is unused (or vice-versa), or if
dual-speed operation with two unconnected and uncoordinated domains is needed for the
application.
Each DS880 has its own internal power supply, and is easily added to an existing 10
or 100Mb network. DS880s are suitable for wiring closet shelf, table-top or vertical mounting.
www
.
GarrettCom . com
6
Magnum DS880 Dual-Speed Stackable Hubs
2.2.1 Magnum DS880 Chassis
The Magnum DS880 chassis houses one main PC board, a bridge module daughter-
Installation and User Guide (05/01)
board in the Model DS880-B, and an internal power supply unit. The front side of the chassis
has eight RJ-45 twisted-pair ports and one cascading (UP-LINK) switch for Port 8 on the right.
LEDs to indicate operating status are on the left front side. There are power (PWR)
and bridge-inside (BR)
indicators for the unit.
There are activity (ACT)
1
2
3
4
5
6
7
8
1
2
3
4
5
6
7
8
PWR BR
UPLINK
100
LK
RX
ACT
COL
and collision (COL)
100 10
indicators for each of the
10Mb and 100Mb domains,
Magnum DS880 Dual-Speed Hub
set unto a “square” arrangement, for visual indication of the operating status of each domain.
And there are link (LK), receive (RX) and speed (100) indicators for each port. (See Section
1.1 “Specifications” for a technical description of the LEDs). The unit has a cooling fan on the
bottom left corner which sends warm air out away from the unit to the rear. Stacking cables
connect in the rear (see Section 2.3 for stacking information).
The AC power cord connector, a universal recessed-male IEC type, is in the left
rear of the chassis. The internal power supply is auto-ranging for any AC power input of 115 -
230 vac, 50 - 60 Hz. (An internal DC power supply is optional).
2.2.2
10 / 100 Speed Auto-sensing
All eight RJ-45 twisted pair ports support auto-sensing for speed, independent of the
other ports. Speed-sensing is performed by the DS880’s electronics in accordance with the
standards of the IEEE 802.3u auto-negotiation standard. If the connected device or node
indicates that it is capable of 100Mb speed, then operation on that port will be at 100Mb/s. If
the connected device does not positively indicate that it is capable of 100Mb speed, then the
operation on that DS880 port will be at 10Mb/s. Of course, the hubs’ auto-negotiation technique
is only for 10 / 100 speed, and does not provide for any full-duplex operation.
When a port is connected and LINK is present, the speed on that port that has been
sensed by the DS880 hub will be indicated by the ‘100’ LED for that port. The ‘100’ LED is ON
when 100Mb speed is sensed, and is OFF when 10Mb speed is in use. When a port is not
connected, the ‘100’ LED corresponding to that port will be blinking to indicate that it is trying
to auto-negotiate. (See section 4.3 for operation of the LED’s).
www
.
GarrettCom . com
7
Magnum DS880 Dual-Speed Stackable Hubs
2.3 Stacking Magnum DS880s
Up to four Magnum DS880s can be stacked to operate as one 10/100 dual-speed
Installation and User Guide (05/01)
repeater with up to 32 dual-speed ports. Normally, one Magnum DS880-B hub per stack is
needed to provide a
switched interconnection
between the two separate
OUT
OUT
IN
IN
100Mb and 10Mb traffic
domains in the stack.
Additional stacked units
are normally Model
DS880-A “add-on” units,
which cost less.
OUT
IN
OUT
IN
FAN EXHAUST
Figure 2.3 : Magnum DS880’s stacked. Cables connect between “Out” and “In” Ports
The DS880-B models with the bridge module inside look the same as the DS880-A
units (no bridge inside) from the outside. The “BR” LED on the front will light up when power
is applied to indicate that a DS880 is a -B (bridge inside) model. (The “BR” LED will be off if
the unit is a Model DS880-A). The DS880-B models cannot be stacked together, as their
internal bridges would not be able to function properly when more than one is present. (Note
that two DS880-B units may be cascaded to operate together, however). Use DS880-B models
un-stacked, or with only 1 Model DS880-B in a DS880 stack. See Section 2.7, Example 3.
When stacking DS880’s, please make sure to use only the shielded 9-inch long
stacking cable provided with each DS880-A unit. The cable length is designed to provide
proper operation of up to four DS880 units in a stack, and longer cables or unshielded cables are
not permitted as they will not operate properly at 100Mb speeds.
The 9-inch length is enough to provide for side-by-side stacking. This can be
convenient when locating the DS880s in a rack, for example, as two DS880s will fit side-by-side
on a tray in a standard 19” rack space.
When connecting DS880s in a stack, use the stacking cable to connect the “Out”
stacking port from one DS880 unit to the “In” stacking port of the other. Push in the cable
connectors until they snap in firmly. Also, leave space in the left-rear area for the exhaust of the
internal cooling fan in each DS880 unit. See Figure 2.3 above.
www
.
GarrettCom . com
8
Magnum DS880 Dual-Speed Stackable Hubs
Installation and User Guide (05/01)
2.4
Bridge Module between the 10Mb and 100Mb Domains
Bridge Module
Figure 2.4 : Internal view of
DS880-B with bridge
module installed
Magnum DS880-B’s contain a factory-installed bridge module to interconnect the two
traffic domains, filtering and selectively forwarding packets to allow only necessary packets to
cross between the domains. This enables all of the users and nodes connected into either
domain, whether 100Mb or 10Mb, to talk to each other, and it keeps local traffic on one domain
from consuming any of the bandwidth of the other domain.
The bridge operates in the store-and-forward mode, which filters out bad packets and
maintains optimum performance in both domains. Packet forwarding delay is only 5µs (plus
packet time), much less than traditional store-and-forward bridge products, enabling the
DS880s to maintain high network performance. The bridge has 8K node address capacity,
suitable for use in large networks. Addresses are self-learning so that filtering / forwarding of
10Mb and of 100Mb packets is maintained correctly even when users move their connection, or
change speed, or power down.
The DS880-B’s bridge module is implemented as a daughter board. DS880 units have
an LED on the front labeled ‘BR’ that will be ‘ON’ when the module is installed internally.
Power any DS880 unit on and if the BR LED is ON, it is a Magnum DS880-B unit.
NOTE : Only one Magnum DS880-B (with a bridge module built-in) is
allowed per repeater stack. Thus, if the DS880s in a stack have more than one
BR (bridge) LED ‘ON’, it is an illegal configuration.
2.5
Up-link Switch on Port 8 for Cascading
The unit has an up-link switch for Port # 8, located on the right-front side of the hub.
It enables the port’s cable to either connect to a user station ( = position) or to be cascaded to
another hub (X position). (See Section 4.4 for more details about up-link). Like all DS880
ports, Port # 8 is a dual-speed port which will sense the speed of the connected device. The up-
link switch operates the same, whether Port # 8 is connected to either 100Mb or 10Mb devices.
When the up-link port is used to cascade two DS880 hubs or stacks together, the auto-
sensing feature will cause the connecting link to operate at 100Mb speed.
www
.
GarrettCom . com
9
Magnum DS880 Dual-Speed Stackable Hubs
2.6 Features and Benefits
Supports 10 or 100Mb network connections on each of eight RJ-45 ports
Installation and User Guide (05/01)
„
Magnum DS880 Dual-Speed 10 / 100 hubs combine two logical hubs . . . one at 10Mb
and one at 100Mb . . . in one physical box supporting two traffic domains. Each port
can operate at either 10 or 100Mb, independently of the other ports.
„
Auto-sensing for speed, 10 or 100Mb on each port
All ports support 10/100 auto-negotiation for speed, operating separately on each
port. Any mix of 10Mb and 100Mb users can be connected to the ports. Speed-
sensing is continuous. Individual ports can change to 100Mb or 10Mb speed at any
time, adapting automatically to any changes in the connected device’s speed. Speed-
sensing complies with IEEE 802.3u, providing interoperability with other products.
„
An internal switch connects the 10 and 100Mb domains on Model DS880-B
Model DS880-B has an internal switch for filtering / forwarding traffic between the 10
and 100Mb domains, allowing all connected devices to talk to each other. High
performance switching provides full bandwidth in each domain, unaffected by local
traffic on the other domain. One DS880-B per stack supports switching for all ports.
„
Stackable for flexible expansion
Magnum DS880s can be stacked up to four units high for 32 ports, each 10 / 100 dual
speed. As additional units are added in a stack, the 10 and 100Mb traffic domains are
expanded automatically to support the new ports at either 10 or 100Mb speed.
„
Installation is “Plug and Play”, Operation is Transparent to Software
The Magnum DS880-B operates as a hardware switch, only forwarding those packets
from each domain that are needed on the other domain. Internal address tables are
self-learning, enabling users to change port connections or 10 / 100 domains without
affecting operations. The switch in the DS880-B will not affect any standard software
applications or SNMP network management platforms.
„
Small Enclosure Enables Use in Offices and Labs
The compact packaging of Magnum DS880s allows them to be installed in offices and
labs, or virtually any location within reach of a standard AC wall outlet. They comes
in a durable metal enclosure for table-top or wall-mounting. They have an internal
auto-ranging power supply for use worldwide. (Models with a 48vdc internal power
supply are optionally available).
www
.
GarrettCom . com
10
Magnum DS880 Dual-Speed Stackable Hubs
2.7 Applications
Installation and User Guide (05/01)
Example 1 : A Magnum DS880-B serves a small office with mixed speed requirements. Some
users operate at 100Mb, and some users and utility devices (such as print servers) run at 10Mb.
All share the same hub, and talk to each other via the bridge module inside. Any node can
change speed at any time without affecting network operation or impacting other users.
1
2
3
4
5
6
7
8
PWR BR
1
2
3
4
5
6
7
8
UPLINK
100
LK
RX
ACT
COL
Print Server
Router
100
100
100
Server
10
100
100
Users
Figure 2.7.1 : DS880-B connects combinations of 10Mb and 100Mb network devices
Example 2 : Where there are existing 10Mb hubs and users, they can easily be cascaded into
any port of the DS880-B. This allows simple plug-and-play addition of 100Mb ports to an
existing 10Mb network without having to change it. Nodes that are capable of 100Mb speed can
be moved to any DS880 dual-speed port, and will automatically operate at the higher speed.
The dual-speed ports on the DS880-B can be used for adding 100Mb users or for
accommodating existing high performance users. The 100Mb traffic does not use the bandwidth
of the 10Mb domain, so overall performance of the network is improved.
Figure 2.7.2 :
1
2
3
4
5
6
7
8
P
W
R
B
R
1
2
3
4
5
6
7
8
U
PLIN
K
10
0
A
C
CT
OL
L
R
K
X
DS880-B adds a new
100Mb domain to
existing 10Mb
network
Print Server
Router
10 Mb Hub
100
100
100
Server
1
2
3
4
5
6
7
8
9
1
0
1
1
1
2
100
100
Users
10
10
10
10
www
.
GarrettCom . com
11
Magnum DS880 Dual-Speed Stackable Hubs
Installation and User Guide (05/01)
Example 3 :
For additional expansion, DS880s can be expanded by stacking DS880-A “add-on”
units. The additional stacked ports are all auto-sensing dual-speed, and can be used at either
10Mb or 100Mb on a per-port basis.
The stacking cables connect the DS880 units and carry the signals for both the 100Mb
and the 10Mb domains. In a stack, all 10Mb ports are together in a 10Mb traffic domain while
all 100Mb ports are similarly together on a separate 100Mb traffic domain. When one DS880-B
unit with a bridge inside is present in a stack, its bridge will support all of the ports in the stack
and enable network traffic to move between the two stacked domains.
A Magnum DS880 stack operates as one dual-speed repeater. A dual-speed repeater is
both a 10Mb hub and a 100Mb hub at the same time. This means that the 10Mb traffic domain
obeys all of the rules of 10Mb shared Ethernet networks (hop counts, cable types, cable
distances, etc.) and can be treated as one 10Mb repeater accordingly. Separately, the 100Mb
traffic domain obeys all of the rules of 100Mb Fast Ethernet shared networks (hop counts,
PDVs, cable types, cable distances, etc.) and can be treated as one 100Mb repeater. Both traffic
domains function within the same physical DS880 hub or stack of hubs.
1
1
1
2
2
2
3
3
3
4
4
4
5
5
5
6
6
6
7
7
7
8
8
8
1
8
2
2
2
3
3
3
4
4
4
5
5
5
6
6
6
7
7
7
UPLINK
PWR BR
100
A
C
CT
OL
LK
RX
1
0
0
1
0
UPLINK
1
8
PWR BR
100
LK
RX
A
C
CT
OL
1
0
0
1
0
1
8
UPLINK
PWR BR
100
LK
RX
A
C
CT
OL
1
0
0
1
0
1
2
3
4
5
6
7
8
1
8
2
3
4
5
6
7
PWR BR
UPLINK
100
LK
RX
A
C
CT
OL
1
0
0
1
0
Figure 2.7.3 :
Stackof Magnum
DS880’s operate as
one 10/100 dual-speed
repeater
Print Server
Router
10 Mb Hub
100
100
100
Server
1
2
3
4
5
6
7
8
9
10 11 12
100
100
Users
10
10
10
10
When expanding an Ethernet or Fast Ethernet installation, the Magnum DS880 Hubs
are ideally suited for connecting servers and stations that have (or may have in the future ! )
mixed speeds. Each traffic domain or segment has its own local traffic with the Magnum
DS880-B performing bridge-isolation of one domain from the other, filtering and selectively
forwarding 10Mb and 100Mb packets between the two domains. This keeps the traffic between
the domains to a minimum and provides peak performance on both domains.
www
.
GarrettCom . com
12
Magnum DS880 Dual-Speed Stackable Hubs
3.0 Magnum DS880 Installation
Installation and User Guide (05/01)
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 500C.
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.
This chapter provides instructions for installing the Magnum DS880 hubs
3.1
Locating Magnum DS880 Dual-Speed Hubs
The location of a Magnum DS880 Dual-Speed Hub is dependent on the physical
layout of the network. Typically the hub is placed where combinations of 10Mb and 100Mb
network devices need to be connected to communicate with each other. The compact size of the
unit allows it to be conveniently placed in an office or lab area, and it can also be either shelf of
wall-mounted (see instructions in 3.1.2 below). Wall-mounting brackets are included, usable for
single units (but not for stacks). The width of two DS880 units will fit in a 19” rack when they
are side-by-side.
Locate an AC receptacle that is within six feet (2 meters) of the intended Magnum
DS880 site. The rugged metal case of the Magnum DS880 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 unit so that cooling can occur from the
small fan in the bottom-rear while the unit is in operation.
3.1.1
Table-Top or Shelf Mounting
The Magnum DS880 Dual-Speed Hub can be easily mounted on a table-top or any
suitable horizontal surface, and has four rubber feet to provide stability without scratching
finished surfaces. When stacked, the rubber feet also provide separation between units for the
exhaust of the rear cooling fan.
www
.
GarrettCom . com
13
Magnum DS880 Dual-Speed Stackable Hubs
3.1.2 Wall (or Vertical Surface) Mounting
Each Magnum DS880 Dual-Speed Hub is shipped with two metal mounting brackets
Installation and User Guide (05/01)
(and screws) to allow the unit to be mounted in nearly any desired orientation or position. The
brackets are attached to the metal hub case using one of the metal screws for each bracket and
attaching to the Magnum DS880 through the round hole of the bracket. A user-supplied screw
attaches the bracket to the mounting surface. It is recommended that the brackets be attached to
two opposite corners of the unit. When properly attached, the brackets will extend slightly
below the base of the unit to allow clearance for the rubber feet and the cooling fan exhaust.
3.2
Connecting Ethernet Media
The Magnum DS880 Dual-Speed Stackable Hubs can be connected to the following
two media types: 100BASE-TX and 10BASE-T. CAT 5 cables should be used when making
100BASE-TX connections. When the ports are used as 10BASE-T ports, CAT 3 may be used.
In either case, the maximum distance for unshielded twisted pair cabling is 100 meters (328 ft).
Media
IEEE Standard
10BASE-T
Connector
RJ-45
Twisted Pair (CAT 3)
Twisted Pair (CAT 5)
100BASE-TX
RJ-45
NOTE : It is recommended that high quality CAT. 5 cables (which work for both 10Mb and
100Mb) be used whenever possible in order to provide flexibility in a mixed-speed
network, since dual-speed ports are auto-sensing for either 10 and 100Mb/s.
3.2.1
Connecting Twisted Pair (RJ-45, CAT 3 or CAT 5, Unshielded or Shielded)
The following procedure describes how to connect a 10BASE-T or 100BASE-TX
twisted pair segment to the RJ-45 port. The procedure is the same for both unshielded and
shielded twisted pair cables.
1. Using standard twisted pair media, insert either end of the cable with an RJ-45 plug into
the RJ-45 connector of the port. Note that, even though the connector is shielded, either
unshielded or shielded cables and wiring may be used.
2. Connect the other end of the cable to the corresponding device.
3. Use the LINK LED to ensure proper connectivity by noting that the LED will be
illuminated when the unit is powered and proper connection is established. For Port #
8, if the LINK LED is not illuminated, change the setting of the up-link switch. If this
does not help, ensure that the cable is connected properly and that the device on the
other end is powered and is not defective.
www
.
GarrettCom . com
14
Magnum DS880 Dual-Speed Stackable Hubs
3.2.2 100Mbps Collision Domain Diameter, Cable Distances and PDV Calculations
The 100Mbps Collision Domain Diameter is the length of the longest path between
Installation and User Guide (05/01)
any two devices in a single collision domain. A collision domain is defined as a cluster of
network devices which are connected by means of a repeater or repeaters such that no bridging
devices are present between any two devices in the cluster. In order to install an IEEE 802.3u
compliant Fast Ethernet network, the collision domain . . regardless of the actual network
topology . . must be less than 512 BT (Bit Times). Bit Times are related to media type as shown
in Table 3.2.2a.
Table 3.2.2a: Worst case round-trip delay for Fast Ethernet media*
Media Type
Round-trip delay in
Bit Time per Meter (BT/m)
Fiber Optic
1.000
1.112
1.112
1.140
Shielded TP cable
Category 5 Cable
Category 3, 4 Cable
*Worst case delays taken from IEEE Std 802.3u-1995, actual delays may be less for a particular cable.
Contact your cable supplier for exact cable specifications.
Each Fast Ethernet device component also has an associated BT delay which depends
on the physical signaling system employed. Table 3.2.2b shows each Fast Ethernet device
component and the associated BT delay. A “DTE” is an end node, such as a user station. Note
that there is only one DTE pair associated with any device-to-device path.
Table 3.2.2b: Worst case round-trip delay for Fast Ethernet device components*
Component
Round-trip delay in Bit Times (BT)
2 TX DTEs
2 FX DTEs
100
100
1 FX and 1 TX DTE
100
1 T4 and 1 TX or FX DTE
Class I Repeater
127
140
Class II Repeater with any
combination of TX and FX ports
92 **
**Note, the delay is only 80 Bit Times for
the DS880, front-port-to-front-port.
*Worst case delays taken from IEEE Std 802.3u -1995.
To determine whether a prospective network topology adheres to the collision domain
diameter specification, the following formula should be applied to the worst case path through
the network. The worst case path is the path between the two Fast Ethernet devices (DTEs)
which have the longest round-trip time.
www
.
GarrettCom . com
15
Magnum DS880 Dual-Speed Stackable Hubs
Installation and User Guide (05/01)
PDV = (sum of cabling delays) + (sum of repeater delays) +
(DTE pair delay) + (safety margin)
PDV is the Path Delay Value of the worst case path. For the network to adhere to
IEEE standard, this value must be less than 512 BT. The safety margin is specified in BT and
may be a value between 0 and 5. This margin can be used to accommodate unexpected delays
such as extra long patch cable. A safety margin of about 2 to 4 BT is recommended.
A typical example of a PDV calculation is shown below, and is illustrated in Figure
3.2.2a. Here, an integrator wishes to cascade the 100Mbps collision domains of two Magnum
DS880 Hubs(each having a PDV of 80BT) for use with standard 100m Category 5 user cable
segments (i.e. from computer to hub) and needs to know how long the inter-repeater Category 5
cable segment, used to cascade the hubs, can be. The variable “X” represents the unknown
maximum cascade cable delay.
PDV = X + ((111 + 111) + (80 + 80) + (100) + 2 ) BT < 512 BT
512 > (X + 486) BT
X
< (512 - 486 ) BT, X < 28 BT
Twisted Pair cable length, TL < (28 BT) / (1.112 m/BT)
TL
< 25 meters
⇒
25 m maximum total length for Category 5 inter-repeater segment,
Cat. 5 cable for
cascading
where 111 is the BT delay for
1
2
3
4
5
6
7
8
PWR
BR
UPLINK
1
7
2
8
3
4
5
6
ACT
COL
L
K
RX
100m of Category 5 cable (1.112
BT/m* 100m), 80 is the BT delay
for each Magnum DS880, 100 is
the BT delay for the TX DTE pair,
and a safety margin of 2 was used.
1
2
3
4
5
6
7
8
PWRBR
UPLINK
1
7
2
8
3
4
5
6
ACT
COL
LK
RX
100 m Cat. 5 cables
to user devices
100 m Cat. 5 cables
to user devices
Figure 3.2.2a: Two cascaded Magnum DS880 hubs
The resulting value tells us that a Category 5 cable with a length of up to 30 meters
may be used to cascade the Magnum DS880s. Note that this inter-repeater cable length may be
increased by shortening the lengths of the 100m hub-to-user cable segments.
It is also possible to cascade a group of up to nine Magnum DS880s (serving up to 56
users with full-length 75m cables to each) by using short inter-repeater cable segments. The
following is an example of how to calculate the maximum allowable cascade cable segment
length. An illustration of this example is shown in Figure 3.2.2b, where the hub-to-user cable
www
.
GarrettCom . com
16
Magnum DS880 Dual-Speed Stackable Hubs
Installation and User Guide (05/01)
lengths are up to 100 meters for Cat 5 twisted pair. The variable “X”, the maximum hub-to-hub
cable delay, is calculated as follows:
PDV = X + ((100) + (80 + 80 + 80 )+ (83 + 83) + 2 ) BT < 512 BT
512 > (X + 508) BT,
X
< 4 BT
Twisted pair user cable length, TL < (4 BT) / (1.112 m/BT)
TL < 3.6 meters for two hub-to-hub cascading cables
⇒
2
meters (6 ft.) length max. for each of the cascade segments,
In the above example, 80 is the BT delay for 75m of Category 5 cable (1.112 BT/m), 80 is the
bit time delay for each Magnum DS880 front-to-front ports, 100 is the BT delay for the TX DTE
pair in the user stations, and 2 BT is the safety margin applied.
Figure 3.2.2b: Multiple
1
2
3
4
5
6
7
8
PWR BR
ACT
UPLINK
1
7
2
8
3
4
5
6
LK
RX
COL
cascaded Magnum DS880 hubs
Note that the cascading
of multiple Magnum DS880 hubs
is a capability beyond what
1
2
3
4
5
6
7
8
PWRBR
UPLINK
1
2
3
4
5
6
7
8
1
7
2
8
3
4
5
6
PWR BR
UPLINK
1
7
2
8
3
4
5
6
ACT
COL
LK
RX
ACT
COL
LK
RX
industry standards normally
permit, and is different from what
competitive Class II hub products
normally allow. This additional
cascading level and cable length is
2 meter Cat. 5 cable
for cascading
All user devices connected
via Cat. 5 twisted pair cable
of up to 75m length.
due to the relatively shorter bit time (80 BT actually measured, for front-port-to-port) delay of
the 100Mbps domain of the Magnum DS880 vs. the industry standard delay of 92 BT for Class
II repeaters. The installation flexibility and network growth potential is accordingly better with
Magnum DS880s than with hubs that merely meet the standard.
Table 3.2.2c shows maximum cable lengths for common network configurations using
industry standard repeater PDV numbers. Calculations such as above should be performed
using measured PDV data supplied by the equipment manufacturer in important installations.
Table 3.2.2c: Maximum segment lengths for common network configurations
Number Repeater
of Hubs Hop Count
Max. User
Segment Repeater (Cascade)
Max. Inter-
Notes
Lengths (m)
100.0
Length (m)
n.a.
1
2
2
3+
www
1
2
2
3
All ports TX
100.0
92.0
60.0
5.0
20.0
1.0
All ports TX
All ports TX
All ports TX
.
GarrettCom . com
17
Magnum DS880 Dual-Speed Stackable Hubs
Installation and User Guide (05/01)
Instructions for connecting the Magnum DS880 Dual-Speed Hubs to the various Fast
Ethernet media are given in the following sections.
3.2.3
Connections to NICs which support Auto-Negotiation
The Magnum DS880 Dual-Speed Hub will function properly with NICs (Network
Interface Cards) which support Auto-Negotiation. The Magnum DS880 will establish link with
any NIC which can send and receive the Fast Link Pulse (FLP) coding for the 100BASE-TX
signaling system. When connecting a NIC to the DS880, it may be necessary to reload the NIC
drivers on the user device if the NIC has been communicating with a protocol other than
100BASE-TX (such as 10BASE-T). When 100Mb operation is agreed and in use, the 100Mb
LINK/ACT LED is illuminated, steady ON if no traffic or blinking when there is traffic.
3.3
Powering the Magnum DS880
Magnum DS880 Dual-Speed Hub incorporates an internal universal power supply, and
has a recessed male IEC connector for the AC power cord in the rear. A six-foot 115 VAC 60Hz
power cord is supplied with each unit shipped within the United States and Canada.
Each Magnum DS880’s auto-ranging power supply supports installation environments
where the AC voltage is from 90 to 260 volts with an input frequency between 47 and 63 Hz,
and consumes a maximum of 20 watts. In order to power down the unit, simply unplug either
end of the AC power cable.
www
.
GarrettCom . com
18
Magnum DS880 Dual-Speed Stackable Hubs
Installation and User Guide (05/01)
4.0
OPERATION
This chapter describes the function and operation of the Magnum DS880 hubs.
Dual-Speed Functionality
4.1
The Magnum DS880-A handles the two different traffic domains separately (unless it
is stacked with a DS880-B). The DS880-B provides switched (bridged) connectivity between
the Ethernet (10Mb/s) and Fast Ethernet (100Mb/s) domains. It joins the two network domains
for unified operation, and filters/ forwards packets in both directions to maximize bandwidth
utilization and performance. Magnum DS880s are hardware plug-and-play devices. There is no
software set-up to be done at installation or for maintenance. The functions of the DS880s are
described in this manual.
Each time a packet is received on one domain of the bridge module, the decision is
taken to either to filter or forward the packet. Errored packets are always filtered. For good
packets, the filter and forward decisions are made based on the destination address contained in
each packet. If the destination address is on the same domain from which the packet originated,
then it is filtered and not forwarded to the other domain. If the destination address is not found
to be a match in the address table for the originating domain, then it is forwarded to the other
domain. If it is a new node address coming in which the switch did not previously know about,
it “learns” the new address and puts it in the correct port address table. See “Address Learning”
for more details.
This diagram below shows the filter / forward logic for both domains.
Magnum DS880-B
10Mb Domain : 10Mb packets are
100Mb Domain : 100Mb packets are
forwarded when the destination address is
NOT in the 100Mb domain address table.
forwarded when the destination addresse is
NOT in the 10Mb domain address table.
10Mb Domain : 10Mb packets are
filtered when the destination address is
in the 10Mb domain address table.
Bridge Module
100 Mb Domain
100 Mb Traffic
10 Mb Domain
10 Mb Traffic
10
BUS 100
100Mb Domain : 100Mb packets are
filtered when the destination address is
in the 100Mb domain address table.
Figure 4.1 : Filtering vs. Forwarding in Dual Speed 880-B
www
.
GarrettCom . com
19
Magnum DS880 Dual-Speed Stackable Hubs
Installation and User Guide (05/01)
Packet
Source
10 Mb
10 Mb
10 Mb
10 Mb
100 Mb
100 Mb
100 Mb
100 Mb
Source
Destination
Address
Not in table
In table
Not in table
In table
Not in table
In table
Address Table
Filter/Forward
Action
Forward
Filter
Forward
Filter
Forward
Filter
Address
Not in table
Not in table
In table
Maintenance
Add source to table
Add source to table
None
In table
None
Not in table
Not in table
In table
Add source to table
Add source to table
None
Not in table
In table
Forward
Filter
In table
None
Table 4.1: DS880 Dual-Speed Hub Functionality
1.
Address Learning (Address Table Maintenance)
The Magnum DS880-B bridge module is a state machine design which has a total
address table capacity of 8K addresses. With a large address table, a Magnum DS880 can serve
the needs of a medium-sized to large network. Table 4.1 shows what filter / forward action the
Magnum DS880-B will take in each packet-processing situation, and when a new node address
will be added to the internal Address Table. When a new node-address packet comes into a port
for the first time, then the new source address is “learned” at the same time that the packet is
forwarded. After learning, subsequent packets from the same node address are routinely
processed. The address tables are flushed periodically to update the network status and to purge
any inactive stations from the tables of both domains.
2.
Throughput Increase
By selectively forwarding packets from each domain to the other domain based on its
switching (bridging) logic, the Magnum DS880-B increases the available bandwidth for the
users on both sides of the network. As shown in Figure 4.1, it keeps the local traffic on each side
contained, preventing unnecessary packets and bad packets from traveling to the other domain
and using up bandwidth needlessly over there. This results in more available network
bandwidth on both sides and a throughput increase on for all users on both domains.
1.1
Software Transparency
4.1.1
The Magnum DS880-A and -B Dual-Speed Hubs need no software set-up and are
transparent to system and application software, including network management
software.
www
.
GarrettCom . com
20
Magnum DS880 Dual-Speed Stackable Hubs
Installation and User Guide (05/01)
4.2
Port Speed Settings for 10,100Mbps Or 10/100Mbps Mode only
10/100
Port 4
100
Port 3
Port 2
Port 1
SW3
SW2
ON
10/100
OFF
100
Port 8
Port 7
Port 6
Port 5
ON
OFF
Figure 4.2: Switch Settings for 10/100Mbps and 100Mbps Speed
The latest Magnum DS880 unit is equipped with Switches for setting Port Speed.
The SW2 and SW3 switches are located on the right side of the main board as shown in the
figure 4.2 above. These switches allow the user to set the speed at 10, 100Mbps or 10/100Mbps
auto-sense. The unit has been set at 10/100Mbps at the time of shipping.
The Switch SW3 represents port#1 to 4 and the switch SW2 port#5 to 8 as shown in the Fig 4.2
above. The switches has 8 Dip-switches each. Every two contiguous Dip-switches represent one
single port. To fix the speed at 100Mbps, both DIP-switch position have to slide towards the 100
side. In the above Fig 4.2 the Switch SW3 has
10/100
been fixed 10/100Mbps and Switch SW2 at
Port 4
Port 3
100Mbps. Setting the port at 10Mbps is little
port# 1,2,3 has been fixed at 10Mbps
Port 2
bit tricky. The user has to slide the odd number
Port 1
of Dip-switch to ON (or 10/100) position and
ON
OFF
even number to reverse
Figure 4.2a Speed settings at 10Mbps (OFF or 100) position as shown in the Fig 4.2a above.
www
.
GarrettCom . com
21
Magnum DS880 Dual-Speed Stackable Hubs
4.3 Auto-negotiation and speed-sensing
Installation and User Guide (05/01)
All eight RJ-45 ports independently support auto-negotiation for shared
10BASE-T and 100BASE-TX modes. When the ‘100’ LED is flashing, it means that the
corresponding port is sending out auto-negotiation pluses out that port. When a connection is
made, the other device should respond and both sides should agree to the speed being
advertised. Depending upon the device connected, it will either advertise at 10Mb or 100Mb
speeds. Silence means the port defaults to 10Mb.
When the ‘100’ LED is steady ON, the port has auto-negotiated for 100Mb
operation and is processing packets at 100Mb/s, When it is OFF, it is at 10Mb/s. If a DS880
port is connected to a non-negotiating device, it will default to 10Mb speed. Since Magnum
DS880s are hubs, they always operate in the shared or half-duplex mode on all ports.
4.4
LED’s
PWR
: Illuminates GREEN to indicate AC power is applied to the unit.
BR
: Bridge Module LED-
ON when a bridge module is present in the unit (model DS880-B)
OFF when no bridge module is present ( model DS880-A)
: Two collision LED’s, one for each traffic domain, 10 and 100Mb
Blinks intermittently when a collision occurs.
COL
ACT
100
: Activity (Send or Receive) for each traffic domain, 10 and 100Mb
: Speed LED, per port. Flashing when auto-negotiating (No LINK)
Steady ON when the port speed is 100Mbp/s, OFF for 10Mbp/s
: LINK LED, per port. Illuminates GREEN when a working
connection is established between the port and the attached device.
: Activity LED, per port. Flashes GREEN to indicate that the port is
receiving data from the attached device, i.e., there is activity on the
port.
LK
RX
4.5
Up-link Switch
The Magnum DS880s have one up-link slide switch,
UP-LINK
used with port 8. This allows repeater-to-repeater connections
without a special cross-over cable. It works the same for 10Mb
or 100Mb connections.
Set the slide switch to the “=” position for twisted pair cabling from the DS880
port to a user device, or to the “X” position for cross-over or up-link segment connections
from the DS880 port to a repeater or hub. Verify proper switch position by noting the port’s
LINK LED status, which is illuminated when a proper link is made.
www
.
GarrettCom . com
22
Magnum DS880 Dual-Speed Stackable Hubs
5.0 TROUBLESHOOTING
All Magnum Ethernet products are designed to provide reliability and consistently
Installation and User Guide (05/01)
high performance in all network environments. The installation of the Magnum DS880 10/100
Dual Speed Stackable Hub is a straightforward procedure (see INSTALLATION, Section 2.6);
the operation is also straightforward and is discussed in Section 4.
Should problems develop during installation or operation, this section is intended to
help locate, identify and correct these types of problems. Please follow the suggestions listed
below prior to contacting your supplier. However, if you are unsure of the procedures described
in this section or if the Magnum DS880 10/100 Dual Speed Stackable Hub is not performing as
expected, do not attempt to repair the unit; instead contact your supplier for assistance or contact
GarrettCom Customer Support.
5.1
Before Calling for Assistance
1.
If difficulty is encountered when installing or operating the unit, refer back to the
Installation Section of the applicable chapter of this manual. Also check to make sure
that the various components of the network are interoperable.
2.
3.
4.
Check the cables and connectors to ensure that they have been properly connected and
the cables/wires have not been crimped or in some way impaired during installation.
(About 90% of network downtime can be attributed to wiring and connector
problems.)
Make sure that an AC power cord is properly attached to each Magnum DS880 10/100
Dual Speed Stackable Hub unit. Be certain that each AC power cord is plugged into a
functioning electrical outlet. Use the PWR LEDs to verify each unit is receiving
power.
If the problem is isolated to a network device other than the Magnum DS880 10/100
Dual Speed Stackable Hub product, it is recommended that the problem device is
replaced with a known good device. Verify whether or not the problem is corrected.
If not, go to Step 5 below. If the problem is corrected, the Magnum DS880 10/100
Dual Speed Stackable Hub and its associated cables are functioning properly.
5.
If the problem continues after completing Step 4 above, contact your supplier of the
Magnum DS880 10/100 Dual Speed Stackable Hubs unit or if unknown, contact
www
.
GarrettCom . com
23
Magnum DS880 Dual-Speed Stackable Hubs
Installation and User Guide (05/01)
5.2
When Calling for Assistance
Please be prepared to provide the following information.
A complete description of the problem, including the following points:
a. The nature and duration of the problem;
1.
b. Situations when the problem occurs;
c. The components involved in the problem;
d. Any particular application that, when used, appears to create the problem;
2.
3.
An accurate list of GarrettCom product model(s)involved, with serial number(s).
Include the date(s) that you purchased the products from your supplier.
It is useful to include other network equipment models and related hardware,
including personal computers, workstations, terminals and printers; plus, the
various network media types being used.
4.
A record of changes that have been made to your network configuration prior
to the occurrence of the problem. Any changes to system administration
procedures should all be noted in this record.
5.3
Return Material Authorization (RMA) Procedure
All returns for repair must be accompanied by a Return Material Authorization
(RMA) number. To obtain an RMA number, please use this URL -
https://rma.garrettcom.com/rma/rma_request_noaccount.php to fill out the form. Please
have the following information readily available:
Name and phone number of your contact person.
Name of your company / institution
Your shipping address
Product name
Serial Number (or Invoice Number)
Packing List Number (or Sales Order Number)
Date of installation
Failure symptoms, including a full description of the problem.
www
.
GarrettCom . com
24
Magnum DS880 Dual-Speed Stackable Hubs
Installation and User Guide (05/01)
GarrettCom will carefully test and evaluate all returned products, will repair
products that are under warranty at no charge, and will return the warranty-repaired units to
the sender with shipping charges prepaid (see Warranty Information, Appendix A, for
complete details). However, if the problem or condition causing the return cannot be
duplicated by GarrettCom, the unit will be returned as:
No Problem Found.
GarrettCom reserves the right to charge for the testing of non-defective units
under warranty. Testing and repair of product that is not under warranty will result in a
customer (user) charge.
5.4
Shipping and Packaging Information
Should you need to ship the unit back to GarrettCom, please follow these instructions:
1. Package the unit carefully. It is recommended that you use the original container if
available. Units should be wrapped in a "bubble-wrap" plastic sheet or bag for
shipping protection. ( You may retain all connectors and this Installation Guide.)
CAUTION Do not pack the unit in Styrofoam "popcorn" type packing material.
:
This material may cause electro-static shock damage to the unit.
2. Clearly mark the Return Material Authorization (RMA) number on the outside of the
shipping container.
3. GarrettCom is not responsible for your return shipping charges.
4. Ship the package to:
GarrettCom, Inc.
47823 Westinghouse Dr.
Fremont, CA 94539-7437
Attn.: Customer Service
APPENDIX A: WARRANTY INFORMATION
GarrettCom, Inc. warrants its products to be free from defects in materials and
workmanship for a period of three (3) years from the date of shipment by GarrettCom.
During this warranty period, GarrettCom will repair or, at its option, replace
components in the products that prove to be defective at no charge other than shipping
and handling, provided that the product is returned pre-paid to GarrettCom.
This warranty will not be effective if, in the opinion of GarrettCom, the product
has been damaged by misuse, misapplication, or as a result of service or modification
other than by GarrettCom.
GarrettCom reserves the right to make a charge for handling and inspecting any
product returned for warranty repair which turns out not to be faulty.
Please complete the warranty card as this acts as a product registration, and mail
it to GarrettCom within two weeks of your purchase.
www
.
GarrettCom . com
25
Magnum DS880 Dual-Speed Stackable Hubs
Installation and User Guide (05/01)
APPENDIX B : Optional 48V DC Power Supply, Addendum
B1.0
SPECIFICATIONS - FOR DUAL-SPEED DS880 HUBS
Power Supply (Internal 48 VDC Option)
DC Power Connector: 3 terminals: “-“, “GND”, “+”
Input Voltage: 36 - 70 VDC (auto-ranging)
Power Consumption: Model DS880: 12 watt typical, 20 watts max.
With the exception of the power supply, all specifications and functions of
Magnum DS880-48VDC models are identical to those listed in Section 1.
B2.0
48V DC SOURCE OPTION, THEORY OF OPERATION
The 48VDC power option is designed using diodes inside on each DC power input
line behind the two external power connection terminals, so that the power from an external
POWER SWITCH
source can only flow into the hub. This
HUB
SUPPLY
allows the hub to operate only whenever
+
A+
A-
FUSE
-
DC power is correctly applied to the two
inputs. It protects the hub from incorrect
DC input connections. An incorrect
CHASSIS
GND
GND
polarity connection, for example, will neither effect the hub, nor its power supply internally, nor
will it blow the fuse in the internal power supply.
The power switch (included on premium-priced NEBS-certified units only) is used for
powering the hub on and off when it is placed into or taken out of service.
B3.0
APPLICATIONS
Magnum DS880 Dual-Speed Hubs are easily installed in a variety of applications
where 48 VDC power is used as the primary power source. The 48VDC power configuration
provides an Ethernet networking solution utilizing a special power supply in hubs with a proven
track record.
The solution is particularly useful in the telecommunication industry, where it is
common for facilities to operate on 48VDC power. Such companies include regular and wireless
telephone service providers, Internet Service Providers (ISPs) and other communication
companies. In addition, many high availability equipment services, such as broadcasters,
publishers, newspaper operations, brokerage firms and other facilities often use a battery backup
system to maintain operations in the event of a power failure. It is also frequently used for
computer system backup, management and operations monitoring equipment.
www
.
GarrettCom . com
26
Magnum DS880 Dual-Speed Stackable Hubs
B4.0 INSTALLATION
This section describes the installation of the 48 VDC power source leads to the 48
Installation and User Guide (05/01)
VDC power terminal block on the Magnum DS880s. (see figure below).
_
Figure B4.1: 48 VDC Terminal Block
GND
+
ON
on Magnum DS880-48VDC
OFF
The 48 VDC terminal block on
the Magnum DS880s is located on the rear
of the unit and is equipped with three (3)
screw-down lead posts. The leads are
36-70VDC
identified as negative (-), positive (+), and chassis ground (GND). The actual connection
procedure is very straightforward. To avoid the confusion of -48V or +48V power supply,
use a digital voltmeter to measure the output voltage and figure out the +VE Lead. The
more +VE voltage terminal lead from the +48V or-48V power supply should be
connected to the post leveled “+” and then the rest. Ensure that each lead is securely
tightened.
On the premium-priced NEBS-compliant Magnum DS880-48V models, an ON-OFF
switch is included, located in the rear at the power input. This can be used in conjunction with
power connections, and as a RESET for the hub’s electronics.
B4.1
UL Requirements
1. Minimum 14 AWG cable for connection to a Centralized DC power source.
2. Fastening torque of the lugs on the terminal block: 9 inch pound max.
3. Centralized DC Power Source cable securement, use at least four cable ties to secure
the cable to the rack at least 4 inches apart with the first one located within 6 inches
of the terminal block.
B5.0
OPERATION
Operation of the Magnum DS880s with the optional 48VDC power supply is identical
to that of the standard AC-powered models.
B6.0
TROUBLESHOOTING
Please refer to Section 5.0 for troubleshooting
www
.
GarrettCom . com
27
|