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What does the Ethernet standard dictate for the meaning of 1 Gb ethernet?

Does it dictate full duplex 1 Gbps, or a shared pipe between the two directions?

merlin2011
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1 Answers1

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https://en.wikipedia.org/wiki/Gigabit_Ethernet

Half-duplex gigabit links connected through hubs are allowed by the specification, but the specification is not updated any more and full-duplex usage with switches is used exclusively.

ceejayoz
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    This is also highlighted by the specs of an enterprise-level switch - a 24 port gigabit switch will have 48gbps of switching capacity. I think even virtually all consumer switches have a back plane capacity matching the number of ports at full duplex. – Mark Henderson Aug 19 '14 at 21:29
  • @Mark_Henderson even some very pricey enterprise gear is "over-subscribed", where the switching fabric cannot handle all ports at line rate. Sometimes the limitation is not bits per second, but packets per second. The venerable Cisco Catalyst 6500 series is notoriously over-subscribed, and even the latest Broadcom Trident 2 based switches from numerous vendors cannot fill all 10 GbE ports with small packets. – rmalayter Aug 20 '14 at 00:59