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Media Converters
Introduction
Using Media Converters
Black Box Explains
Media Converters.
It seems simple enough: To convert
between different media, you need a
media converter. However, it's not as
simple as that. There are three different
types of media converters, and you need
to find the right type for your scenario and
application.
Switched Media Converter
The most common type of media
converter is the switched media converter.
These are economical, easy to build and
simple to install. A switched media
converter uses standard chipsets for
switches, which enables the converter to
run different speeds. Switched media
converters autosense 10-, 100- or 1000-
Mbps speeds.
However, many things you encounter
with a switch also apply to a switched
media converter. Not all Ethernet frames
(packets) pass through the switched media
converter and you may experience some
latency.
If you need a media converter for your
office network — for internet, e-mail,
printing and file sharing — you can't go
wrong with a switched media converter.
Transparent Media Converter
These media converters are fully
transparent within their designated
protocol. So any frame coming in on "Side
A" gets converted and is output on "Side
B" in the same manner. Because most
media converters are generally converting
optical to copper Ethernet, only a
conversion from electrical to
opto-electronic is done.
Unfortunately, these media converters
need to run on the same speed on both
sides. This applies to the bandwidth (10,
100 or 1000 Mbps) and the half-/fullduplex
setting.
Protocol-transparent Media Converter
The other main use of a media
converter is to change between singlemode
and multimode. In this case, a
protocol-transparent media converter that
works transparently and is independent
from the can work Ethernet, Token Ring,
ATM and Fibre Channel because they just
adopt the wavelength. They're available
for different speeds.
Why is this so important to know
Today, IP networks are used for more
than just sending e-mail, accessing the
Internet and print servers. Special devices
exist for transferring audio, video, KVM,
telephony and other services. Because not
all these devices work with standard TCP/IP
communication at standard frame length,
you could experience unexpected results.
For example, audio data transferred by
UDP broadcast traffic have frames blocked
by switches where "Broadcast Storm
Protection" is enabled. And there are
proprietary systems sending very big
frames (Jumbo frames), which normal
switched media converters block as well.
Switched media converters also produce
latency on your IP network, although one
switched media converter will not do any
harm. However, having more than one in
your IP network can degrade your
roundtrip time.
Switched media converters are easy and
economical, but make sure they're best for
your applications.
Advantages of Media Converters
Cost Comparison
Fibre Ethernet Switches can be very expensive. At the end of
2009, a 16 port branded fibre switch (low end) was costing upwards
of £4K, whilst a branded Gigabit Fibre Switch module for a core
switch, was typically costing just under £10K. Black Box Media
Converters allow you to use existing fully functioned twisted pair
switches and convert to fibre externally. This option can also
provide flexibility and future proofing in one easy to install
solution, at the same time as dramatically reducing the costs
involved.
A fully functioned 16 port twisted pair Gigabit Ethernet switch
can cost as little as £150 depending upon model, and combined
with a 16 port Gigabit media conversion chassis, a total solution of
under £3.5K provides all the functionality required. But in
addition, if the type of cable changes again, i.e. from a MultiMode
cable to a Single-Mode cable, the chassis, power supply and any
management system can be kept and only the actual cards will
need to be replaced. A lot of the cards provide 10/100/1000Mbps
connectivity on the twisted pair port and enable you to begin
converting at either 10 or 100Mbps, yet provide all the future
proofing you need to take you right up to 1 Gigabit to the
desktop. This saves having to buy a 10/100Mbps fibre media
converter now, and replace it in a year or two with a gigabit
version. So if you are using a 10/100 or 100Mbps switch currently,
but are thinking of moving to Gigabit later on, purchasing a Black
Box 10/100/1000Mbps Media Converter system will provide all the
connectivity you require today and tomorrow.
Some of our latest Media Converters use SFP sockets for the
fibre port. The advantages of SFP sockets is that they are another
way of providing future proofing. SFP modules are very convenient
and easy to use and also very easy to replace, without the expense
of replacing the entire switch. And SFP’s can be replaced one port
at a time, reducing the need to buy new switches just because a
few ports are now using fibre.
Moving up to 10Gigabit Ethernet networks, XFP’s provide the
same functionality as SFP’s but provide the 10Gigabit speeds
required for today’s high speed core networks.
Available in copper (CX4) and both multimode and single-mode
fibre versions, these XFPs provide the same future proofing as SFP’s
in one compact, easy to install, practical solution.
Purchasing an XFP based 10Gigabit Ethernet switch now, means
you can provide the high speed network required today, whilst
always being ready for the higher speed networks of tomorrow.
Black Box XFP’s – because you don’t know what the future will
bring.
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