Information Technology Reference
In-Depth Information
There will be a gradual move from the current 100 Mbps network speeds to
1000 Mbps, and soon to 10 Gbps. There are even higher speeds in development.
There may be no immediate need (or budget) to convert your entire network to
1000 Mbps, but you should probably not install any new cable that will not serve
that speed. And you will be surprised how quickly you will develop a need for at
least some of the connections to be gigabit.
So, how do you plan for the future? How do you put in a 1000 Mbps network?
Should you use copper wire or consider fiber? Can you hedge your bets? Let's see.
100/1000 Mbps Networking Compatibility
If you currently are using 10/100 Mbps Ethernet or 16 to 100 Mbps Token-Ring,
you may not be using LAN wiring components that will move you to higher speeds
such as 1000 Mbps. Or you may be getting along (maybe limping along) on 10
Mbps for your current network. These lower speeds are much less demanding in
their need for transmission media than the high-speed networks, such as Fast
Ethernet and Gigabit Ethernet.
For example, 10BaseT will run at a workstation-to-hub distance of 100 m on
Category 3 cable. If you try to upgrade such a network to 10 times the speed, how-
ever, it will probably fail. Gigabit speeds would be impossible.
So, what can you do if you may need to upgrade to 1000 Mbps? The answer
is to install a LAN wiring system that meets the performance specifications for the
higher speed now; it will operate very satisfactorily at the lower speed for the pres-
ent and will provide additional service as you upgrade to high speeds.
One sure way to provide such a wiring system is to use the TIA/EIA-568-C
standard for a Category 6 or Augmented Category 6 (AC6) cable system. 1 Even
Category 5e wiring is designed to support full 1000 Mbps speeds, and Cat AC6 and
7 will go to 10 Gb. At the same time, Category 5e, 6, AC6, and even 7 2 wiring will
fully support lower network speeds, such as 10/100BaseT Token-Ring, and CDDI
as well as intermediate speeds for ATM and Fast Token-Ring. For that matter, it will
also support voice, ISDN, and T1/E1 circuits very nicely. Table 4.1 shows a table
that summarizes the supported uses of Category 3-7 installations.
“True” Category 5e, 6, AC6, and proposed Cat 7 wiring should be used for a
single application, not shared between data and voice, for instance. If your needs are
uncertain, you may wish to overwire your workstations by pulling more than one
1 Although Augmented Category 6 is an emerging standard, most manufacturers already have compo-
nents that meet the requirements.
2 Category 7 may use connectors that are not compatible with lower categories, but you can get
adapter cords.
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