R&M Data Center Handbook

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In addition, the advantage of factory preassembled
cabling systems comes up
during installation in the form of time
savings, which also saves costs. In case
capacity must be expanded because of an
increase in IT devices, these cabling
systems and in turn the actual IT application
can be linked to one another and put into
operation easily and as quickly as possible
by internal operational personnel.
These ready-to-operate systems for so-called
“plug-and-play installations” are often freely
configurable as well, and have reproducible
quality that is of the highest quality and
therefore excellent transmission properties.
Pre-assembled shielded cable fitted with 6 A modules from R&M
In addition, no acceptance test is required after these cabling systems are installed, as long as the cables and
connection elements were not damaged during the installation. Furthermore, these solutions provide high investment
protection, since they can be uninstalled and reused.
Trunk cable fitted with MPO/MTP ® connectors from R&M
The increase in density of glass fiber cabling in data centers has led
to parallel optic connection technology, and in turn to innovative
multi-fiber connectors that are as compact as an RJ45 plug
connection. Multi Fiber Push-On (MPO) technology has proven itself
to be a practicable solution in this area. This is because four or even
ten times the number of plug connections must now be provided to
ports for 40/100 gigabit Ethernet. This high number of connectors
can no longer be managed with conventional single connectors.
This is why the multi-fiber MPO connector, which can contact 12 or
24 fibers in a minimal amount of space, was included in the IEEE
802.3ba standard for 40GBase-SR4 and 100 GBase-SR10. It is
therefore clear that an MPO connector with 12, 24 or even up to 72
fibers can no longer be assembled on site. The use of the MPO
connectors therefore always also implies the use of trunk cables
which are pre-assembled and delivered in the desired length.
Please find more detailed information on parallel optic connection technology using MPO in section 3.10.1.
3.9.3 Plug Connectors for Twisted Copper Cables
The RJ45 connection system has been being developed
over decades, from a simple telephone plug to a highperformance
data connector. The RJ45 plug and jack
interface was defined by ISO/IEC JTC1/SC25/WG3 as
the international ISO/IEC 11801 standard, and is considered
a component in universal cabling systems. It is
used as an eight-pole miniature plug system in connection
with shielded and unshielded twisted copper cables.
The RJ45 is the most widely distributed of all data
connectors, and is used in both the area for connecting
terminal devices like PCs, printers, switches, routers,
etc. – in the outlets and on connection/patch cables – as
well as in distribution frames for laying out and distributing
horizontal cabling.
The transmission properties of the RJ45 connection system are essentially determined through its small dimensions.
Parameters like frequency range, attenuation, crosstalk and ACR are significant in determining transmission
behavior. Crosstalk is especially critical, since pairs which are guided separately in the cable must be laid over
one another in the connection system (1-2, 3-6, 4-5, 7-8).
Connector characteristics must be adapted to those of the cable within the structured cabling system. In order to
compare and adjust these characteristics, connectors, like data cables, connection cables, patch cords and other
cabling components, are defined by the categories already mentioned.
R&M Data Center Handbook V2.0 © 08/2011 Reichle & De-Massari AG Page 113 of 156