| Type |
Cable used |
IEEE standard | Distance |
| 10BASE2 (obsolete) |
Thick coaxial |
185 m |
|
| 10BASE5 (obsolete) |
Thin coaxial |
500 m |
|
| 10BASE-T (obsolete) |
UTP Cat 3 |
100 m |
|
| 100BASE-TX |
UTP Cat 5 |
IEEE 802.3u |
100 m |
| 100BASE-FX |
Fiber Multimode |
400 m |
|
| 1000BASE-LX |
LongWavelength Laser |
10
km (SM), |
|
| 1000BASE-SX |
ShortWwavelength Laser |
220 m with 62.5u MM 550 m with 50u MM |
|
| 1000BASE-ZX |
Extended wavelength |
100 km, SM |
Which wavelengths are used in optic fibers?
650nm,850nm in plastic optic fiber
850nm,1300nm in multimode graded index optic fiber
1300nm, 1490 to 1625nm in singlemode optic fiber
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Whether these are ultraviilet or infra-red?
We are ablel to see between 400nm to 700nm. Above 700nm is infra red. So fibers use infra red.
850,1300,1550 are the common wavelengths used in fibers.
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Why we have to use certain specific wavelengths like 850,1300,1550?
Attenuation is due to scattering and absorption.
When wavelength increases, attenuation decreases, That is why, we use above 850.
The frequencies lying between 850 and 1300 as well as between 1300 and 1500 are called as WATER BANDS.
The fiber is having water vapour. This vapour absorbs the em waves in these range very easily.
plastic fiber have low absorption, so even at 650nm we are able to use it.
====================================================
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1300nm is long wave, 850nm is shortwave
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