Hey all I am just wondering before I do this if its possible to connect 2 SFP sockets to each other in order to bring in the fiber connection and then take it back out the same way? enter image description here So in the image above, Pin 1 would hook up to Pin 1 on the second SFP socket. Pin 2 would hook up to Pin 2 on the second SFP socket, etc etc...

I'm doing this so that I can bring in the SFP connection into a server case and then once inside the server case I need to hook it up to a motherboard inside there that has the SFP connection.

To better illustrate what I am trying to accomplish: enter image description here

this is what the ONT fiber hook up looks like that I am wanting to use (green connector). enter image description here

  • \$\begingroup\$ you gotta be kidding me. i'm looking to learn about actually interfacing this stuff with power and fpga \$\endgroup\$ – flow Jan 13 '18 at 4:27

I would expect that this isn't possible due to the I2C configuration interface and other system status/control signals defined on the connector. You would also need the appropriate power supplies on the board for the modules, so it couldn't be a passive adapter or passthrough board. To coordinate the TX/RX high-speed differential pairs, you would also need to swap pins and likely include DC blocking capacitors on those lines.

What pre-SFP interface are you planning on using? If you are using a consistent optical interface, you could look into short fiber jumpers that have a socket for exposing to the user and use just one (rather than three) SFP on the internal board.

  • \$\begingroup\$ Its just a motherboard firewall that has a SFP+ socket on it. I do not want to run the fiber into the server and connect it to the motherboard. I rather have it connect on the outside of the server and have a short fiber cable from inside connect to the motherboard. \$\endgroup\$ – StealthRT Aug 7 '16 at 16:44
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    \$\begingroup\$ My additional suggestion was to go Motherboard->Fiber Jumper->panel-mount optical connector->Other fiber. This keeps the signal optical when crossing the server case boundary and makes it easy to (dis)connect as required without any custom hardware. \$\endgroup\$ – user2943160 Aug 7 '16 at 17:20
  • \$\begingroup\$ happen to have some links to those needed components? \$\endgroup\$ – StealthRT Aug 7 '16 at 18:19
  • \$\begingroup\$ @StealthRT Here's one digikey.com/product-detail/en/te-connectivity-amp-connectors/… and one that mounts in a round hole digikey.com/product-detail/en/assmann-wsw-components/… \$\endgroup\$ – DoxyLover Aug 7 '16 at 20:34
  • \$\begingroup\$ (I have not tested SFP+, just copper and optical SFP). On optical SFPs, the I2C interface is mostly for monitoring and retrieving data (model, type, speed), it is not really needed for setting up communications. Of course, you must activate the TX and correctly power the SFPs. There can be slight differences between each model. \$\endgroup\$ – TEMLIB Aug 7 '16 at 22:57

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