Difference between FC and SX

[James Kim(LG)]

Hello,

We recently ordered some RX server with a SX/FC combo card. I am very new to SX(IEEE 802.3Z) ethernet type, and have a question.
I never thought or had doubt about difference between FC and SX. But after ordering this unit, I am very curious about the difference of two.
What difference between FC and SX makes one technology support 2/4/8Gbps and another only support 1Gbps? They are using same LC cables to transfer data. Also, if they are same data transfering technologies, what makes SAN switches differ from LC switches? What makes SAN switches more expensive than Fiber Ethernet?

[Uwe Zessin]

FC layer 1 uses different clocking (even at 1 GigaBit) and FC layer 2 uses a different frame format on the media.

FC is not such a mass-market as SAN and one of the rules is not to lose a single frame.

[Cass Witkowski]

The SX connector is for Ethernet. The FC connector is for SAN. Both use fiber cables but completely different beasts.