Fibre Channel transmission speed

bbao used Ask the Experts™

hi FC experts

i am reading the Wikipedia article of Fibre Channel and got a bit confused about the transmission rates of FC described in the article.

Fibre Channel

in the table of Fibre Channel Speed Variants, the Line-Rates are from 1.0625 to 21.04 Gbaud (eq. Gbps??) while the throughput is from 200 to 5,100 MBps (Mbps??).

in the table of Optical Carrier Medium Variants, the speeds are from 100 to 400 MByte/s (eg. 1/8 Mbps??) for single-mode fibre and multi-mode fibre with varied Transmitters.

so basically... how fast is FC?  Gbps level or Mbps level?

does Line-Rate of FC mean the *internal* transmission speed of a FC switch, while Medium-Seed for the *external* speed between switches?? the bottleneck is here?

many thanks in advance.

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A 4Gbps FC has a linerate which means a bit is send or receive at 4Gbps.
Now, you have:
-Correction control to send/receive a BYTE
-Full-duplex which means they are adding the incoming and outgoing throughput to get 800MB/s

So, for this 4Gb FC example, you have:
-Incoming traffic at 400MB/s
-Outgoing traffic at 400MB/s

NB: Don't forget that 1Gbe Ethernet is "only" about 110MB/s
Top Expert 2014
Just an aside;
Those line rates are for the opto-electronics, the actual glass fiber doesn't have an associated line rate, some company in Japan has managed to crank it up to a terabit per second, must have some pretty fancy lasers.
bbaoIT Consultant


so that means its Line Speed (bandwidth) is from 1Gbps while the actual data transfer speed is from 100MB/s??
Yes, a 1Gbs line speed have a data transfer speed of about 110MB/s.

NB: Please note that a "full duplex" line would have this 110MB/s for a simultaneous inbound AND outbound traffic (A marketing bastard may even add those throughput ...but that is nonsense)

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