Systran SCRAMNet SC150 User manual

SCRAMNetÒ
ÒÒ
Ò+
++
+Network
Media User’s Guide
Document No. D-T-MU-MEDIA###-A-0-A7

FOREWORD
The information in this document has been carefully checked and is believed to be accurate; however, no
responsibility is assumed for inaccuracies. Systran reserves the right to make changes without notice.
Systran makes no warranty of any kind with regard to this printed material, including, but not limited to,
the implied warranties of merchantability and fitness for a particular purpose.
ãCopyright 2002 Systran Corporation. All Rights Reserved.
®is a registered trademark of Systran Corporation.
SCRAMNetÒis a registered trademark of Systran Corporation. U.S. patent #4,928,289
STÒis a registered trademark of the AT&T Corporation.
ULTRA FOX™ is a trademark of the Optical Cable Corp.
Any reference made within this document to equipment from other vendors does not constitute an
endorsement of their product(s).
Revised: January 22, 2002
Systran Corporation
4126 Linden Avenue
Dayton, OH 45432-3068 USA
[phone] (U.S. only)
[phone]

Copyright 2002 i MEDIA USER’S GUIDE
TABLE OF CONTENTS
1. INTRODUCTION ......................................................................................................................................1-1
1.1 How To Use This Manual.........................................................................................................1-1
1.1.1 Purpose...................................................................................................................1-1
1.1.2 Scope......................................................................................................................1-1
1.1.3 Style Conventions ..................................................................................................1-1
1.2 Related Information ..................................................................................................................1-1
1.3 Quality Assurance.....................................................................................................................1-1
1.4 Technical Support .....................................................................................................................1-2
1.5 Ordering Process.......................................................................................................................1-2
2. PRODUCT OVERVIEW ...........................................................................................................................2-1
2.1 Overview...................................................................................................................................2-1
2.1.1 Transmitter and Receiver Pairs ..............................................................................2-1
2.1.2 Network Cabling....................................................................................................2-1
2.1.3 Connectors .............................................................................................................2-1
3. MEDIA ACCESS CARDS.........................................................................................................................3-1
3.1 Overview...................................................................................................................................3-1
3.2 Fiber-Optic MAC......................................................................................................................3-1
3.3 Coaxial MAC............................................................................................................................3-1
3.3.1 Modes of Operation................................................................................................3-2
3.4 Redundant Operation ................................................................................................................3-4
4. COAXIAL CABLE ....................................................................................................................................4-1
4.1 Overview...................................................................................................................................4-1
4.2 Coaxial Construction ................................................................................................................4-1
4.3 Specifications............................................................................................................................4-2
4.4 Cable Noise...............................................................................................................................4-2
4.4.1 Static Noise ............................................................................................................4-2
4.4.2 Common Mode ......................................................................................................4-2
4.4.3 Crosstalk ................................................................................................................4-2
4.5 SMA Connector ........................................................................................................................4-2
5. FIBER-OPTIC CABLE ..............................................................................................................................5-1
5.1 Overview...................................................................................................................................5-1
5.2 Fiber Construction ....................................................................................................................5-1
5.2.1 Multimode Cable....................................................................................................5-1
5.2.2 Singlemode Cable ..................................................................................................5-1
5.2.3 Protective coating...................................................................................................5-1
5.2.4 Nomenclature .........................................................................................................5-3
5.3 Specifications............................................................................................................................5-3
5.3.1 Standard Link Fiber-Optic Specifications ..............................................................5-3
5.3.2 Long Link Fiber-Optic Specifications....................................................................5-3
5.3.3 Fibre-Optic Cables .................................................................................................5-4
5.4 Cleaning....................................................................................................................................5-5
5.5 Fiber-optic Connectors..............................................................................................................5-5
5.5.1 Connector Requirements........................................................................................5-5
5.5.2 ST Connector .........................................................................................................5-6
6. FIBER OPTIC BYPASS SWITCH ............................................................................................................6-1
6.1 Overview...................................................................................................................................6-1
6.2 Functionality.............................................................................................................................6-1
6.3 Benefits.....................................................................................................................................6-1
6.4 Bypass Mode ............................................................................................................................6-2
6.5 Inserted Mode ...........................................................................................................................6-2
6.6 Considerations ..........................................................................................................................6-3
7. PERFORMANCE.......................................................................................................................................7-1

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Copyright 2002 ii MEDIA USER’S GUIDE
7.1 Overview...................................................................................................................................7-1
7.2 Fiber-optic Cable ......................................................................................................................7-1
7.2.1 Light-Power Budget...............................................................................................7-1
7.2.2 Bandwidth-Length Budget .....................................................................................7-2
7.2.3 Signal Skew ...........................................................................................................7-3
7.3 Coaxial Cable............................................................................................................................7-5
8. BIT-ERROR RATE....................................................................................................................................8-1
8.1 Overview...................................................................................................................................8-1
8.1.1 Signal-to-noise Ratio..............................................................................................8-1
8.1.2 Calculations............................................................................................................8-2
8.1.3 Tables.....................................................................................................................8-2
FIGURES
Figure 3-1 Fiber-Optic MAC..........................................................................................................................3-1
Figure 3-2 Coaxial Media Access Card ..........................................................................................................3-2
Figure 3-3 Redundant Transceiver Operations ...............................................................................................3-4
Figure 3-4 Cabinet Kit with Dual Media Access Cards..................................................................................3-6
Figure 4-1 Coaxial Construction.....................................................................................................................4-1
Figure 4-2 Coaxial Dimensions ......................................................................................................................4-1
Figure 4-3 SMA Connector ............................................................................................................................4-2
Figure 5-1 Fiber-optic Cable (side view)........................................................................................................5-2
Figure 5-2 Fiber-optic Cable (end view).........................................................................................................5-2
Figure 5-3 ST Connector – 3M Model 6100...................................................................................................5-6
Figure 6-1 Ring with Bypass Switches...........................................................................................................6-2
Figure 6-2 Fiber Optic Bypass Switch Connections .......................................................................................6-4
Figure 7-1 Data Flow......................................................................................................................................7-4
TABLES
Table 7-1 Typical Connector Losses ..............................................................................................................7-2
Table 7-2 Examples Of Fiber-optic Extender Cable Order Numbers .............................................................7-3
Table 8-1 Bit-Error Rate Calculation Table 1.................................................................................................8-3
Table 8-2 Bit-Error Rate Calculation Table 2.................................................................................................8-3
Table 8-3 Bit-Error Rate Calculation Table 3.................................................................................................8-4
Table 8-4 Bit-Error Rate Calculation Table 4.................................................................................................8-4

Copyright 2002 1-1 MEDIA USER’S GUIDE
1. INTRODUCTION
1.1 How To Use This Manual
1.1.1 Purpose
This document describes the network cabling hardware accessories for the SCRAMNet+
Network.
1.1.2 Scope
This manual provides information about the Media Access Card (MAC), coaxial cable,
fiber-optic cable, the Fiber Optic Bypass Switch, fiber-optic cable performance, and bit-
error rate.
This information is intended for systems designers, engineers and network installation
personnel. You need at least a systems level understanding of general computer
processing, and hardware operation to effectively use this manual.
1.1.3 Style Conventions
· Hexadecimal values are written with a “0x” prefix. For example, 0x03FF.
· Switch, signal and jumper abbreviations are in capital letters. For example,
RSW1, J5, etc.
· Register bits and bit ranges are specified by the register identification followed
by the bit or range of bits in brackets [ ]. For example, CSR6[4], CSR3[15:0],
ACR[1,2].
· Bit values are shown in single-quotes. For example, set bit 15 to ‘1.’
1.2 Related Information
SCRAMNet Network Cabinet Kit Hardware Reference (Doc. No. D-T-MR-CABKIT) - A
physical and functional description of the Compact and Expanded cabinet kits, including
installation.
1.3 Quality Assurance
Systran Corporate policy is to provide our customers with the highest quality products
and services. In addition to the physical product, the company provides documentation,
sales and marketing support, hardware and software technical support, and timely product
delivery. Our quality commitment begins with product concept, and continues after
receipt of the purchased product.
Systran’s Quality System conforms to the ISO 9001 international standard for quality
systems. ISO 9001 is the model for quality assurance in design, development, production,
installation and servicing. The ISO 9001 standard addresses all 20 clauses of the ISO
quality system, and is the most comprehensive of the conformance standards.
Our Quality System addresses the following basic objectives:
· Achieve, maintain and continually improve the quality of our products through
established design, test, and production procedures.

INTRODUCTION
Copyright 2002 1-2 MEDIA USER’S GUIDE
· Improve the quality of our operations to meet the needs of our customers,
suppliers, and other stakeholders.
· Provide our employees with the tools and overall work environment to fulfill,
maintain, and improve product and service quality.
· Ensure our customer and other stakeholders that only the highest quality product
or service will be delivered.
The British Standards Institution (BSI), the world’s largest and most respected
standardization authority, assessed Systran’s Quality System. BSI’s Quality Assurance
division certified we meet or exceed all applicable international standards, and issued
Certificate of Registration, number FM 31468, on May 16, 1995. The scope of Systran’s
registration is: “Design, manufacture and service of high technology hardware and
software computer communications products.” The registration is maintained under BSI
QA’s bi-annual quality audit program.
Customer feedback is integral to our quality and reliability program. We encourage
customers to contact us with questions, suggestions, or comments regarding any of our
products or services. We guarantee professional and quick responses to your questions,
comments, or problems.
1.4 Technical Support
Technical documentation is provided with all of our products. This documentation
describes the technology, its performance characteristics, and includes some typical
applications. It also includes comprehensive support information, designed to answer any
technical questions that might arise concerning the use of this product. We also publish
and distribute technical briefs and application notes that cover a wide assortment of
topics. Although we try to tailor the applications to real scenarios, not all possible
circumstances are covered.
Although we have attempted to make this document comprehensive, you may have
specific problems or issues this document does not satisfactorily cover. Our goal is to
offer a combination of products and services that provide complete, easy-to-use solutions
for your application.
If you have any technical or non-technical questions or comments, contact us. Hours of
operation are from 8:00 a.m. to 5:00 p.m. Eastern Standard/Daylight Time.
· Phone: [phone] or [phone]
· E-mail: [email protected]
· Fax: [phone]
· World Wide Web address: www.systran.com
1.5 Ordering Process
To learn more about Systran products or to place an order, please use the following
contact information. Hours of operation are from 8:00 a.m. to 5:00 p.m. Eastern
Standard/Daylight Time.
· Phone: [phone] or [phone]
· E-mail: [e-mail]
· World Wide Web address: www.systran.com

Copyright 2002 2-1 MEDIA USER’S GUIDE
2. PRODUCT OVERVIEW
2.1 Overview
Cabling a SCRAMNet+ Network involves four hardware elements:
· The specific transmitter and receiver pairs used by SCRAMNet+
· The fiber-optic cable, which comes in various diameters and optical quality, or
the optional coaxial cable
· The connectors used to link the cable to the transmitter or receiver. Connectors
may also be used to pass the cable through a bulkhead. Connectors also are used
to hook separate cables together into one longer cable. However, this causes
additional power loss and should be avoided.
2.1.1 Transmitter and Receiver Pairs
The transmitter and receiver pairs provide an interface between the network ring and the
SCRAMNet Network node. The fiber-optic transmitter and receiver pairs convert the
incoming light signals to electronic signals, and outgoing electronic signals to light
signals. The coaxial transmitter and receiver pairs convert incoming 50-ohm terminated
single-ended signals to 100 K Emitter Coupled Logic (ECL) differential drive-and-sense
signals, and reverses the process for outgoing signals. The transmitter and receiver pairs
may be on a MAC depending on the SCRAMNet+ product. The MAC can be configured
to completely isolate the node from the network ring.
2.1.2 Network Cabling
The ring topology and bi-polar transmission protocol dictates that there must be two
transmitters and two receivers on each network node. This requires two cable pairs
connecting each node into the network.
Two types of cable are offered: fiber-optic and coaxial cable. Cabling is chosen based on
the distances involved in the application, and whether radio frequency interference (RFI)
or electromagnetic interference (EMI) is likely. Fiber-optic cabling will eliminate the
effects of this interference on the network, where coaxial cabling will not. Coaxial cable
can be used in networks where RFI and EMI are not present in sufficient intensity to
interfere.
2.1.3 Connectors
The fiber-optic cable uses the STâtype connector. The coaxial cable uses the SMA type
connector.

PRODUCT OVERVIEW
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Copyright 2002 3-1 MEDIA USER’S GUIDE
3. MEDIA ACCESS CARDS
3.1 Overview
The MAC receives and transmits network messages. There are two types of MAC; fiber-
optic and coaxial. The MAC can be used on all SCRAMNet host interface boards, cabinet
kit boards, and on the Quad Switch.
3.2 Fiber-Optic MAC
The fiber-optic MAC receiver converts light signals to electronic signals and passes them
to the host. The transmitter converts electronic signals to light signals and sends them on
to the network.
The fiber-optic MAC is available in standard fiber optic (820 nm wavelength) for short
distances and long fiber optic (1300 nm wavelength) for long distances.
BOTTOM VIEW
RECEIVE PAIRTRANSMIT PAIR
INTERNAL/EXTERNAL
POWER JUMPER
Figure 3-1 Fiber-Optic MAC
This fiber-optic card has two power options; host power and standby or battery power.
Jumper J2 in Figure 3-1 controls the power options. Pins 1 and 2 are for normal host
power, and pins 2 and 3 are for standby power. The standby or battery power requires
external connection via the auxiliary connection on the cabinet-kit board or the host-
interface board if no cabinet kit is installed.
3.3 Coaxial MAC
This board receives and transmits messages over coaxial cable. The receive and transmit
signals on the host side are 100 K ECL differential-level drive and sense.
The board, shown in Figure 3-2, can be configured to completely isolate the coaxial
cables from the host, to connect to common (signal) ground, or to the chassis ground. It
can be powered by the host, standby (via the accessory connector), or phantom power. It
can also be configured to supply the control signals to the Quad Switch (C version or

MEDIA ACCESS CARD
Copyright 2002 3-2 MEDIA USER’S GUIDE
higher) via phantom levels on the coaxial cables. (This eliminates the need for the
auxiliary cable on the Quad Switch.)
TRANSMIT PAIR RECEIVE PAIR
BOTTOM VIEW
Figure 3-2 Coaxial Media Access Card
3.3.1 Modes of Operation
The jumpers are installed only from one row of the header to the other. Do not install
between two pins on the same side of the header.
ISOLATE MODE (Default for nodes)
J506 jumper position 1
J507 jumper position 1
J508 jumper position 1
The coaxial outputs are transformer-coupled by high frequency baluns (line-balance
converters), and this is the only connection between the host and the cables. This results
in very high common-mode rejection and no ground loops between systems.
To tie the shields of the coaxial to circuit common (signal) ground, move the jumper on
J506 to position 2.
To tie the shields of the coaxial-to-chassis ground, move the jumper on J506 to position
3.
321
4321
32
1
J506
J507
J508

MEDIA ACCESS CARD
Copyright 2002 3-3 MEDIA USER’S GUIDE
PHANTOM FO_RELAY MODE
Quad Switch End Host End
J506 jumper position 1 J506 jumper position 2
(for shields-to-circuit common) OR
J506 jumper position 3
(for shields-to-chassis common)
J507 jumper position 2 J507 jumper position 3
J508 jumper position 1 J508 jumper position 1
The FO_RELAY output is coupled by a lowpass filter to all the coaxial connectors center
conductors. This allows this “phantom” signal to be decoupled at the other end of the
cables for control purposes. This is used by the Quad Switch (‘C’ version or higher) to
eliminate the need for the accessory cable for control.
PHANTOM SUPPLY MODE
J506 jumper position 2 (for shields-to-circuit common) OR
J506 jumper position 3 (for shields-to-chassis common)
J507 jumper position 4
J508 jumper position 3
The Accessory External power is coupled by a lowpass filter to all the coaxial connectors’
center conductors. This allows this “phantom” power to be decoupled at the other end of
the cables for powering other devices. The primary purpose is to circulate a “backup”
supply for other coaxial MACs that are attached to nodes that may lose power.
Effectively, all the Accessory External power supplies of all the powered nodes are
paralleled. Each powered node is capable of supplying power to its own MAC plus two
others, as a minimum.
321
4321
321
J506
J507
J508
321
4321
321
J506
J507
J508

MEDIA ACCESS CARD
Copyright 2002 3-4 MEDIA USER’S GUIDE
BACKUP PHANTOM SUPPLY MODE
J506 jumper position 2 (for shields-to-circuit common) OR
J506 jumper position 3 (for shields-to-chassis common)
J507 jumper position none
J508 jumper position 2
J508 jumper position 3
This mode can be used alone or in conjunction with the Phantom supply mode. This
mode routes the power coming into the accessory connector from an external supply
(possibly a battery supply to the coaxial MAC). This supply will be connected in parallel
with others of its type and with the on-node “Accessory External supplies” if this is used
in conjunction with the Phantom supply mode.
OTHER MODES
.
NOTE: There are other possible combinations that may be desired. Contact Systran for
assistance because some combinations, other than those above, could be destructive.
3.4 Redundant Operation
Redundant operation requires two sets of MACs with two sets of dual fiber-optic cables
connecting all nodes on the network ring. There are four transmitter lines and four
receiver lines. This configuration ensures network ring message integrity on a node-to-
node basis in the event of the failure of one MAC.
Messages are always sent on both transmitters but only one receiver per node is selected
to pull in data from the network to the node. Figure 3-3 shows the redundant transceiver
configuration and data flow for the particular link selected. All nodes transmit on T1 and
T2. Node A is receiving on R1, Node B on R2, and Node C on R1.
<
<
<
<
<
<
<
<
<
<
<
<
>
>
>
>
>
>
>
>
>
>
>
>
R1 T1 R1 T1
T2 R2
R2 T2 R2 T2
T1 R1
NODE A NODE B
NODE C
Figure 3-3 Redundant Transceiver Operations
Consider the three-node network configuration shown in Figure 3-3. If node A detects
transmission errors from node C or its own receiver is failing, then node A will
321
4321
321
J506
J507
J508

MEDIA ACCESS CARD
Copyright 2002 3-5 MEDIA USER’S GUIDE
automatically switch to the alternate receiver. This does not disrupt the transmission to
node B since both transmit lines are transmitting to both receivers. Only the receiver on
node A is switched. Some incoming data to node A may be initially lost, but will be
retransmitted by the originating node when its message does not return within the time-
out range if error-correction protocol is used. Nodes B and C will continue to operate on
the primary links.
.
NOTE: On power-up, it may be necessary for one node to transmit a message to
establish carrier.
Figure 3-4 shows the P2 Cabinet Kit with dual Media Access Cards for redundant
operation.

MEDIA ACCESS CARD
Copyright 2002 3-6 MEDIA USER’S GUIDE
Figure 3-4 Cabinet Kit with Dual Media Access Cards

Copyright 2002 4-1 MEDIA USER’S GUIDE
4. COAXIAL CABLE
4.1 Overview
SCRAMNet+ can use coaxial cables for distances up to 30 meters in environments where
RFI/EMI emissions are not prevalent. SCRAMNet+ uses an RG-58U cable with an SMA
type connector.
If a coaxial cable SCRAMNet+ installation encounters significant signal errors, then
convert to fiber-optic cable. The noise levels are probably too high for safe coaxial cable
operation.
4.2 Coaxial Construction
SCRAMNet+ coaxial cable is composed of paired, shielded conductors terminated with
SMA connectors. Maximum node separation using coaxial is 30 meters. The
recommended coaxial cable is RG-58U.
BLACK
PVC JACKET
CELLULAR (FOAM)
POLYETHYLENE
DIELECTRIC
COPPER CONDUCTOR
TINNED COPPER
BRAID SHIELD
Figure 4-1 Coaxial Construction
18 AWG
0.116"
0.195"
Figure 4-2 Coaxial Dimensions

COAXIAL CABLE
Copyright 2002 4-2 MEDIA USER’S GUIDE
4.3 Specifications
Requires any coaxial cable capable of a 50-ohm load, RG-58 or better.
4.4 Cable Noise
There are basically three types of noise that may affect the coaxial cabling of a
SCRAMNet network:
· Static
· Common Mode
· Crosstalk
4.4.1 Static Noise
This refers to signal distortion due to the electrical fields radiated by a voltage source,
which has coupled into the signal-bearing circuit. Simple shielding of the full circuit is a
typical means of mitigating this type of interference. It is critical that the shield be
continued to, and completely encompasses, the transmitting and receiving ends of the
circuit if high levels of noise reduction are required. Effective grounding of the shield is
also required. Non-grounded or “floating” shields only partially reduce the effect of the
noise. However, it only needs to be grounded at one end to eliminate ground loops, and
the coaxial Media Access Card provides for this.
4.4.2 Common Mode
Common mode interference is the result of currents flowing between different potential
grounds located at various points within a system. Receivers with very high common-
mode rejection ratios minimize this type of interference. The coaxial Media Access Card
has a very high common-mode rejection in isolated mode.
4.4.3 Crosstalk
This refers to the superimposition of either pulsed DC or standard AC signals carried on
one wire pair to another wire pair in close proximity. The most effective means of
mitigation is removing parallel cables to a distance far enough away from each other to
eliminate the crosstalk.
4.5 SMA Connector
Figure 4-3 shows the dimensions of the SMA coaxial connector.
Figure 4-3 SMA Connector

Copyright 2002 5-1 MEDIA USER’S GUIDE
5. FIBER-OPTIC CABLE
5.1 Overview
Fiber-optic cabling is 62.5/125 micron multi-node, with ST connectors. There are three
types of fiber-optic cable.
· Commercial-grade cables with ST connectors:
Standard commercial grade cables designed to interconnect computers within
a standard environment (duplex pair)
· Hardened Cables with ST connectors:
Cables designed for rugged applications. Hardened cables are mud and water
immersible (matched pairs).
· Plenum-rated cables with ST connectors:
Lightguide building cables designed to run within a building environment.
Plenum cables are fire resistant with a fluoropolymer jacket and are Plenum
listed (duplex pair).
5.2 Fiber Construction
Optical fibers have an all-dielectric construction. The central, circular glass core
propagates the optical signal. Core diameters can vary from 10 microns to over 1000
microns. The layer of glass or plastic cladding surrounding the core serves two purposes.
First, it protects the core from contamination and damage. Secondly, it causes the light
signal to bend back toward the core axis. This bending effect results in a “zigzag” light
path or mode. When there are multiple light paths, the fiber-optic cable is referred to as
multimode. When the fiber is limited to one path, it is called singlemode fiber.
5.2.1 Multimode Cable
Multimode cable includes both step-index and graded-index fibers. In step-index
multimode fiber, the refraction indices between core and cladding are distinctly different.
In graded-index multimode fiber, the indices gradually change from the center to the
outside of the core. This is made possible through the use of layers, each of which has a
slightly greater refraction index. This results in the light rays traveling in the outer layers
to travel faster through the core medium than those at the axis. The effect is to produce
curved paths and to equalize the propagation times.
5.2.2 Singlemode Cable
Singlemode fiber is constructed with only one path—down the axis. The core of a
singlemode fiber must be kept to a diameter of perhaps 10 microns. Singlemode fibers
are typically used for long distance runs.
5.2.3 Protective coating
Figure 5-1 and Figure 5-2 show the various layers of the fiber-optic cable construction.
The outer layer of a fiber-optic cable is the protective coating. This coating is usually
made of epoxy acrylates, and the diameter will vary according to the cable construction.
In “loose buffer” cables, the fiber is free to move within a larger diameter tube. Loose
buffer cables provide the fibers significant protection from external mechanical forces.

FIBER OPTIC CABLE
Copyright 2002 5-2 MEDIA USER’S GUIDE
“Tight buffer” cables usually have another buffer over the 500 micron protective coating.
Tight buffer cables are generally more flexible, and tend to be smaller in diameter than
loose buffer tube cables.
PVC JACKET
STRENGTH
MEMBER
BUFFER CLADDING - 125 MICRONS
SILICA CORE - 62.5
KEVLAR
PVC
Figure 5-1 Fiber-optic Cable (side view)
PVC
KEVLAR
PVC
A
CRYLATE
COATING
FIBER
Paired Fiber Cable
Figure 5-2 Fiber-optic Cable (end view)