Information about Loss budget for transceivers.What is the loss budget for transceivers (SFP+ and XFP)?
The loss is calculated on a number of factors including cable length, fiber type, bandwidth, and attenuation. The data sheets for each SFP, which provides the attenuation and power info for each, are linked in the References section. The loss budget should be calculated with this information.
Additional information on this subject can be found at http://www.thefoa.org/tech/FAQS/FAQ-TEST.HTM#power.