Specifications

G
G7
STRUCTURED
CABLING
NETWORK CONNECTIVITY SYSTEMS
www.signamax-eu.com
10GBaseT and Structured Cabling
Gigabit Ethernet was, until recently, considered to be the limit that would be very difficult to overcome on
metallic structured cabling. Now it is obvious that 1Gbps will not be the maximum transmission rate that can
be achieved on copper twisted pair cables. The new 10GBaseT Ethernet standard that has recently been
published by the IEEE 802.3an group proves this. In the first stage, this new protocol with transmission
speeds of up to 10Gbps will be primarily employed in backbone distribution systems, SAN’s (Storage Area
Networks), and data centres.
At present, the organizations that are involved in setting the standards for structured cabling
(i.e. ANSI/TIA/EIA, CENELEC and ISO/IEC) are trying to find out:
1. Whether it will be possible to run 10GBaseT protocol on currently existing cabling.
2. The definition of new requirements for so-called third generation cabling systems specifically designated
for 10GBaseT.
1. Running 10GBaseT on currently existing cabling
It will be possible to run 10GBaseT for a distance of up to 55 m on current unshielded Category 6 cabling.
The factor that plays an important role in this length limitation is the so-called Alien Crosstalk (see below).
On the other hand, it is believed that current shielded Category 6 and Category 7 cabling will enable to run
10GBaseT even to the full distance (i.e. 100 m). On Category 5e cables, it will not be possible to operate
10GBaseT on any regular cable lengths.
2. New requirements for future cabling systems for 10GBaseT
A “new” Category 6 with bandwidth of up to 500 MHz will be defined. The cable attenuation will correspond
to the requirements for current Category 7. This new category will be referred to as “Augmented Category 6”
or “Category 6a” and will be defined in the upcoming structured cabling specification updates
(e.g. TIA/EIA 568B.2-10). These updates are currently available only in drafts and have not been published
for the wide public yet. The primary aim of the new category 6a is to achieve the full length also on
unshielded cabling.
Similarly to Category 6a, a “new” Category 7 will be defined. It will be referred to as “Augmented Category 7”
or “Category 7a” with bandwidth of up to 1,000 MHz (as compared to 600 MHz of the current Category 7).
One of the most important newly measured parameters for 10GBaseT (especially for unshielded cabling)
will be Alien Cross Talk. It is a parameter that measures crosstalk from external sources (e.g. other cables
in a bundle, electronic devices, telephones, etc.). Presently, it is being worked out how to measure the Alien
Cross Talk. It is estimated that the specifications for the above mentioned categories will be finished in 2007.