Nortel Networks 450 - Manual (Page 244)

Using the BayStack 450 10/100/1000 Series Switch
B-4 302401-D Rev 00
1000BASE-LX Models
The 450-1LX and 450-1LR MDAs provide 1000BASE-LX (1300 nanometers,
long wavelength, Gigabit Ethernet) connectivity. The 450-1LX provides one
1000BASE-LX port. The 450-1LR provides one 1000BASE-LX port and one
LinkSafe redundant port.
Operating Range
Table B-5 lists the operating range for the 1000BASE-LX models:
Table B-4. Worst-Case 1000BASE-SX Power Budget and Penalties
Parameter
62.5 Micron
Multimode Fiber 50 Micron
Multimode Fiber
Units
Modal bandwidth as measured at 850 nm
(minimum, overfilled launch) 160 200 400 500 MHz · km
Link power budget 7.5 7.5 7.5 7.5 dB
Operating distance 220 275 500 550 m
Channel insertion loss 1 , 2 2.38 2.60 3.37 3.56 dB
Link power penalties 4.27 4.29 4.07 3.57 dB
Unallocated margin in link power budget 0.84 0.60 0.05 0.37 dB
1 Operating distances used to calculate the channel insertion loss are the maximum values specified in Table B-1 on
page B-1 .
2 A wavelength of 830 nm is used to calculate channel insertion loss, link power penalties, and unallocated margin.
Table B-5. Operating Range for 1000BASE-LX
Fiber Type
Modal Bandwidth @ 1300 Nanometers with
Minimum Overfilled Launch (MHz · km)
Minimum Range (Meters)
62.5 um MMF 500 2 to 550
50 um MMF 400 2 to 550
50 um MMF 500 2 to 550
10 um SMF N/A 2 to 5000
kombk.book Page 4 Tuesday, June 29, 1999 3:25 PM