Converting SFP to USB

[malwarebuster]

I want to convert serial data from an SFP interface to an isochronous USB stream and vice versa. The signal coming over the SFP is ESCON/SBCON, transmitted at about 200mbps, monodirectional, and with 8/10b encoding. I plan to use an EZ-USB FX2 unit to handle the USB data, and SFP breakout boards are fairly readily available. I wanted to as what I should be using as the intermediary chip to convert the serial data from the SFP to the parallel data stream the EZ-USB expects. I have read about serdes, but these seem to be primarily for higher-speed applications than mine. I think that my signal is too fast for a microcontroller, although I am probably wrong/not looking in the right places. I have also considered using an FPGA, but I don't know what features to look for to meet my needs. I would appreciate any information you can give me on what the best part for this job might be and what to look for when getting it. I am hoping for a solution under $100, but I am open to whatever would work best.

Thank you for any information you can provide.

[m k]

Best part is many times a wrong question, answer is subjective and given variables too many.

Maybe now you already have some thoughts how some more precise solution is better than other first but worse after a second thought.

Is mono directional equal to half-duplex?

If you're tapping SFP you may need two receivers, just like with BaseT connections.
Nowadays one can expect that fast hubs are readily available.