HP 180 Degree Turn User Manual

Page 21

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Note

GE and 10GE use synchronous
physical sublayer !!!
Recommendation: Don't use GE over
copper wires

Radiation/EMI
Grounding problems
High BER
Thick cable bundles (especially Cat-7)

Both GE and 10GE are synchronous physical technologies on fiber. It not
recommended to use GE over copper wires anymore although 802.3ab would
specify it. This is because the whole electrical hardware (cables and connectors)
are re-used from older Ethernet technologies and have not been designed to
support such high frequencies.
For example the RJ45 connector is not HF proof. Furthermore, shielded twisted
pair cables require a very good grounding, seldom found in reality. The Bit Error
Rate (BER) is typically so high that the effective data rate is much lower than
GE, for example 30% only.