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Introduction
Based on growing bandwidth and service demands, the ideal network would
be founded on an all fiber cable infrastructure. The expensive electronics located
along this high-speed network would be equipped with fiber interfaces to take
advantage of the medium’s bandwidth, resistance to EMI, better security, and
freedom from confining distance limitations.
That’s probably not your current network, however. The day may come when
fiber is strung end-to-end and all your networking gear is equipped with fiber
interfaces, but the copper-to-fiber transition is truly an evolutionary process that
won’t come all at once. It’s simply too expensive to abruptly replace all the
copper and all the old equipment—just because some parts of the network
require fiber. Planned migration is a better and more practical idea, using your
current copper infrastructure to maximize profits, while selectively deploying
fiber and fiber gear as needs arise and funds are available.
Media converters are a tactical element that facilitate the fiber network
evolution. Deploying media converters makes it possible to connect networks
that use dissimilar cabling. They are physical-layer devices that straddle two
types of media. In their most common application, they receive electrical signals
on one port and transmit optical signals out the other. Most often this involves
unshielded twisted pair (UTP) and fiber, although there are media converters for
almost every type of cabling: twisted pair, coaxial, multimode and singlemode
fiber. Likewise, there are media converters for most types of networks: Ethernet,
Fast Ethernet, Gigabit Ethernet, ATM, T1/E1, Fibre Channel, and SONET.
There are many preconceived notions and beliefs about media converters and
their usefulness. Myths about Media Converters will address the value they
provide.
Media Conversion
Myths about Media Converters
Myths about Media Converters
Page 1
The Myths…
Media converters don’t belong in my
network…
Media conversion is prolific in every fiber network. Once
you add fiber to your network, media conversion is
inevitable. The real question is where should the media
conversion occur. The switches, router and multiplexers
that populate the network produce electrical signals that
need to be converted before they can be transmitted on
fiber optic cabling. Media conversion can take place on the
network element, optical line card or blade within the
device or by an external media converter. So which
method offers the best value? The answer depends on the
current network infrastructure, capital budget, anticipated
network growth, deployment scale and maintenance
strategy. Often the most economical solution is the
external media converters.
Media converters add cost to my network…
Media converters can save you money. It’s not uncommon
for network equipment with fiber interfaces to cost more
than three times as much as similar gear with copper
interfaces. One network equipment manufacturer, for
example, charges six times as much for a fiber gigabit
network interface card (NIC) as for a copper one. Similar
markups are common for fiber switches and routers, too.
The optical component costs in reduced volumes drive a
majority of the cost increases. With media converters, you
can hang on to the copper equipment and still get the
benefits of deploying fiber. Additionally, optical line cards
also reduce the port density within a network element.
Therefore the high-density solutions touted by equipment
vendors are lost when optical interfaces are deployed.
Often not all of the interfaces require optics for distance
concerns. The required optical extensions may vary from
500 meter to 40 km. These requirements drive differing
optical components. Optical line cards or blades nail up a
set of circuits in a specific configuration, potentially
stranding capacity. Media converters allow you to manage
the diversity of the network and save capital costs.
Media converters are non-standards compliant
elements…
Media converters comply with IEEE802.3 physical layer
standards. This means that the media converter will work
with compliant equipment, including hubs, switches,
routers, and other media converters from any
manufacturer.
The benefit of external media converters is the flexibility
to add functionality to the network as standards evolve,
as well as flexibility in the speed and scope of
implementation. Equipment manufacturers will migrate
to these emerging standards at different rates. External
media converters can provide a faster evolutionary
migration path because of their focus. For instance, the
IEEE 80.3ah™ Ethernet in the First Mile standard has just
been released. Within the standard, a new Operation,
Administration and Maintenance sublayer has be been
defined to support loopback functionality and
performance management data. All major media
converter vendors have announced implementation plans
or products, while network equipment vendors are
delaying their decisions. This new functionality will
enable network engineers to more proactively monitor
their network performance and ultimately reduce
operational expenses. External media converters are
the only current pathway for this solution.
Types of Media Converters
Media converters can be categorized into the
following groups, all of which provide standards-
compliant media transitions and are likely to be
equipped with LEDs that provide power and status
information:
• Workstation units
• Unintelligent data center units
• Intelligent data center units
The distinction between workstation and data center
models is the number of transitions supported.
Workstation models, which are commonly used to
affordably bring fiber to the desk top, provide
transitions for a single pair of cables. Data center
models provide conversion for multiple cable pairs.
Robust management capability is the key difference
between intelligent and unintelligent data center
models. Intelligent models provide significant
management features, such as those described
earlier. An attribute more commonly found in
intelligent models is modularity. These devices
support line card diversity within the same modular
chassis, which makes them highly scalable. They
allow you to add conversion line cards of different
types as required.
Media converters add a point-of-failure in my
network and are not reliable…
Introducing any new device, active or passive, in the
network creates a new potential point-of-failure. The
critical question is how reliable is the new element and
can it be managed or monitored. Media conversion is a
mature, well-tested technology, having proven its
reliability for over a decade in millions of installations. The
introduction of managed multi-port systems provides
intelligence to the media conversion solution. The
platforms offer remote management and monitoring
tools via SNMP, RMON, TL1, and Telnet. The network
engineer is no longer blind to the operation of the media
converter device and can integrate its management into
the network-wide support system.
Media converters clutter up the workstation…
Traditional workstation media converter can create a
cable mess at the desktop. Often, fiber interfaces at the
wall plate require fiber optic cable to lie on the floor
where it can be stepped on or rolled over by a chair. The
converter may be inadvertently kicked or damaged.
These devices are not ideal in any environment. The best
solution is to have the media conversion take place
behind the wall plate where the optical interfaces and
cabling can be protected. Only the copper Ethernet,
which connects to the PC, is exposed. This media
conversion solution is available today and protects the
optical infrastructure better then a stand-alone unit or
fiber NIC.
There are no applications for media converters
in my network…
Media converters can be deployed in multiple
applications whenever the network employs mixed
media. Let's look at the most common applications.
Fiber to the Desktop (FTTD)
Gigabit Ethernet to the desktop is a reality. Fiber to the
desktop is no longer deployed simply to support the
bandwidth-hungry applications of the future. It’s
required now, to meet current challenges. For example,
fiber can be required because the distance between the
switch and the desktop is too great for copper cabling or
because the cable has to be routed through areas with
high EMI levels. There are two options in these cases;
each requires you to lay new fiber, but that’s where the
similarities end. You can start over by replacing the
copper switch and NICs with pricey fiber optic gear. Or
you can keep the existing infrastructure and augment it
with a more cost-effective solution utilizing media
converters to provide the transitions between UTP and
fiber. This is particularly true if only some connections are
too distant for copper or deployed in areas of high EMI.
Myths about Media Converters
Page 2
MAINFRAME
COMPUTER
CONTROLLER
PBX
FIBER
Media Converters
Media
Converter
COPPER
FIBER
MDF
COPPER
MDF
SERVER FARM
ENTRANCE
CABINET
WORKGROUP
HUB
FIBER CABLE
CAT 5+
CABLE
MULTIMEDIA
OUTLET
PA
TCH
CO
RD
Media
Converter
FTTD with media converters
Myths about Media Converters
Page 3
Intra-Office and Inter-Office Extensions
Connecting legacy electronics positioned greater than
100 meters apart is a prime application for the use of
cost-effective media converters to achieve the benefits of
fiber and extend the life of existing capital investments.
These optical extension can be within a single office,
spanning multiple floors or from one office location to
another. The ability to deploy multimode and singlemode
fiber solutions with the same platform provides flexibility
in extending signal a variety of distances. The alternative
to this configuration is to replace the Ethernet switches
with much more expensive optic models.
Network Element A
RJ45 Patch Panel
Network Element B
Ethernet Distribution Frame
RJ45 Patch Panel
Media Converter
Fiber Panel
Media Converter
Router
Ethernet Switch
Intra-Office Optical Ethernet Extensions
Media
Converter
Media
Converter
Media
Converter
Media
Converter
Media
Converter
MC PBX
Switch
OSP
Access
Product
WATC
WATC
WATC
WATC
WATC
WATC
WATC
WATC
WATC
Campus B
Campus C
MC – Main Cross-Connect
IC – Intermediate Cross-Connect
TC – Telecommunications Closet
WA – Work Area
Main Building
Sports Complex
Library
Housing Complex
Student Union
Administration
Building
Lecture Hall
WATC
WATC
WATC
WATC
WATC
WATC
Media
Converter
Media
Converter
Campus Area Network
The distance spanned by a campus area network is likely
to exceed the limitations of copper-based Ethernet.
Serving multiple locations from a centrally managed site
often requires multiple point-to-point Ethernet
extensions. Fiber media converters at one or both ends
are an ideal, cost-effective solution which preserves the
investment in legacy infrastructure.
Myths about Media Converters
Page 6
High Rise Apartment Buildings
In a high-rise apartment, Ethernet services are typically
delivered to the basement of the building through an
ADM, switch or router. Some of the customer hand-offs
may be in the basement while other are required to be in
the end user’s telecom closet. Media converters can
extend the Ethernet signals up the riser to the customer’s
demarcation point. New standards within the Ethernet
domain now allow one to manage the customer
demarcation.
Singlemode Fiber
Singlemode Fiber
Ethernet Switch
Media
Converter
Carrier Services
End-User
Media
Converter
End-User
Media
Converter
End-User
Media
Converter
High-Rise Apartment Application
Myths about Media Converters
Page 7
ADC Media Conversion Solutions
Work Area Solution
ADC’s solution for work area media conversion supports
10Base-T and 100Base-TX UTP and 10Base-FX, 100Base-
SX, and 100Base-FX multimode fiber with auto
negotiation. It is an uncluttered and cost-effective
solution, consisting of two simple components:
• An integrated media converter with conversion
circuitry behind the faceplate. Tx and Rx fiber cables
connect on the rear of the media converter – behind
the faceplate and protected from the office
environment. Each single port media converter fits
into any ADC 6000 multimedia outlet with a 2-port
opening.
• Local power supply through a compact power
adapter that mounts behind the PC or on the desk,
obtaining power through a standard PS/2 mouse
interface with a RJ45 patch cord. The media converter
can also be powered through the USB port of the PC
by means of a simple patch cord or through a
conventional AC/DC wall outlet power adapter.
OptEnet™ Optical Extension Platform
The ADC OptEnet media converter platform is a carrier-
class, intelligent, scalable platform capable of handling
any network’s Ethernet or SONET media transitions.
Integrated intelligence allows you to remotely monitor
system performance and transmit alarm conditions to
upstream operational support systems. A variety of
solutions are supported ranging from 10Mb/s Ethernet,
OC-12 and Gigabit Ethernet.
Key OptEnet features include:
• Modular design enables line card diversity within the
same chassis
• Auto-negotiation eliminates the need for optical line
card upgrade in network elements
• Redundant -48Vdc and AC power supplies
• SNMP, TLI and Telnet support
• Daisy-chain communication interfaces
• 10Base-T, 100Base-TX and 1000Base-T UTP
conversion to singlemode fiber
• Multimode to singlemode fiber conversions
• Medium Dependent Interface Cross-over (MDI-X),
which eliminates network collisions
• NEBS Level 3, UL and FCC standards compliant
Summary
Fiber cabling isn’t an all or nothing proposition. With
media converters there is a cost-effective, standards-
compliant, highly-reliable alternative that allows you to
deploy fiber where it’s required while maximizing your
investment in the existing copper infrastructure.
OptEnet Optical Extension Platform
Work Area Media Conversion
ADC Telecommunications, Inc., P.O. Box 1101, Minneapolis, Minnesota USA 55440-1101
Specifications published here are current as of the date of publication of this document. Because we are continuously
improving our products, ADC reserves the right to change specifications without prior notice. At any time, you
may verify product specifications by contacting our headquarters office in Minneapolis. ADC Telecommunications,
Inc. views its patent portfolio as an important corporate asset and vigorously enforces its patents. Products or
features contained herein may be covered by one or more U.S. or foreign patents. An Equal Opportunity Employer
1296849 10/04 Revision © 2002, 2004 ADC Telecommunications, Inc. All Rights Reserved
Web Site: www.adc.com
From North America, Call Toll Free: 1-800-366-3891 • Outside of North America: +1-952-938-8080
Fax: +1-952-917-3237 • For a listing of ADC’s global sales office locations, please refer to our web site.
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. beliefs about media converters and
their usefulness. Myths about Media Converters will address the value they
provide.
Media Conversion
Myths about Media Converters
Myths. Conversion
Myths about Media Converters
Myths about Media Converters
Page 1
The Myths
Media converters don’t belong in my
network…
Media conversion is prolific in every
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