Extreme Networks BlackDiamond 10808 Installation Manual page 41

Total optical system budget for the SX mini-GBIC is 11.5 dB. Extreme Networks recommends that 3 dB
of the total budget be reserved for losses induced by cable splices/connectors and operating margin.
While 8.5 dB remains available for cable-induced attenuation, the 1000BASE-SX standard specifies
supported distances of 275 meters over 62.5 micron multimode fiber and 550 meters over 50 micron
multimode fiber. There is no minimum attenuation or minimum cable length restriction.
Total optical system budget for the LX mini-GBIC is 13.5 dB. Measure cable plant losses with a 1310 nm
light source and verify this to be within budget. When you calculate the maximum distance attainable
using optical cable with a specified loss per kilometer (for example 0.25 dB/km), Extreme Networks
recommends that 3 dB of the total budget be reserved for losses induced by cable splices/connectors
and operating margin. Thus, 10.5 dB remains available for cable-induced attenuation. There is no
minimum system budget or minimum cable length restriction because the maximum receive power is
the same as the maximum transmit power. There is no minimum attenuation or minimum cable length
restriction.
Mini-GBICs are Class 1 laser devices, and they operate at 3.3 V. Use only Extreme Networks-certified
mini-GBIC devices.
41