====== SFP module (Small Form-factor Pluggable) ======

SFP modules followed on from [[rb:gbic|GBIC]] modules and are used in both ethernet and fibre channel switches (and others too), they are usually optical I/O modules although RJ45 copper Ethernet ones are available. Ethernet modules are most commonly 1GB/s but 10GB/s and higher are available. SFP used for Fibre channel can be 1 or 2GB/s but most common is 4GB/s.


===== LC Fibre =====


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All the optical interfaces are either single or multimode fibre terminated on LC connectors.

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===== RJ45 =====


Although less common, SFP modules can have an RJ45 socket for copper connectivity.

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===== WDM Fibre =====

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Another option is Wavelength Division Multiplex SFP which use two different wavelength for Tx and Rx, so only needing one fibre. This example uses SC single mode ( SC == Stick 'n' Click )

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As this used two wavelengths, the SFP needs an optical splitter, and will have both a laser and receiver on the two prism ports.

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I'm guessing here, but I believe the laser is mounted at the rear with the 3 pins connection to the PCB, and the RX connecctions are on the side with flexible connection to the PCB.
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Closeup of the Prism housing and SC recepticle.