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)

(C) Herbert Haas 2005/03/11

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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.

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