AlibabaOptics

EDFA amplifier
EDFA used to drive the laser or led in FSO or optics communications http://www.alibaba.com/trade/search?SearchText=EDFA+amplifier&Country=CN&CatId=0&IndexArea=product_en&ssk=y

FSO
http://www.alibaba.com/product-gs/223040987/FSO_Free_Space_Optics_Link155M.html