08-12-2011 04:42 AM
I'm facing 2 sites with only 350 meters distance between them, but I need 4 or even 8Gb speed, so we're implementing LW SFPs, but do I need attenuators or am I fine ?
I found the specs of the LW SFP, but I'm not sure how to read these. The output power is 0.5 to -8.4dBm, but it's the input power which I don't quite understand. How do I calculate how much attenuation I need to be sure I dont fry my SFPs ?
08-12-2011 05:24 AM
If you're using standard 10-km LW (1310 nm) SFP or SFP+ modules they're good for any distance between 2 and 10,000 meters, so you don't need attenuators.
ELW lasers such as 1550 nm or WDM-spectrum might require extra attenuation but these lasers are normally only used for truly longhaul links.
Hope this helps,