SX/LX Fiber Cable. 3

[Grenage]

Greetings,

I have never worked with fiber before, 99% of our network is copper with just one fiber connection between two buildings.

The fiber connection is 100mb and we would like to upgrade to 1gb. I believe the existing cable would suffice and I am assuming that it is multimode fibre.

The choice of transievers has been wittled down to 1gb-SX and 1gb-LX, I believe we need the SX.

My question is as follows:

Is it possible to tell multi-mode and single-mode fiber apart by simply looking at it? What are the differences between them?

If anyone could explain the distinction between LX and SX tranceivers I would also be most grateful.

Thank you.
Russell.

 

[jimbopalmer]

reading the sheath may help but looking at the fiber would not help much.

Multi-mode is 50 to 62.5 nanometers in a 125 nm protective layer, single mode is 9 nm in a 125 nm protective layer.

SX will go about 220 meters in 62.5 nm Multimode, while LX will go about 550 meters

SX uses Light Emiting Diodes while LX uses Laser Emitting Diodes, so SX is marginally safer and cheaper if the distance is right. (the sheath may also have distances on it so subtracting them can tell you haw long it is)

I tried to remain child-like, all I acheived was childish.

 

[evilcb]

This site will give you the info you require, and has links to more indepth sites.

http://www.arcelect.com/fibercable.htm

The difference between LC and SC is that LC is high density connector used by SFF GBIC modules

 

[GRMorris]

Thank you both for the information. I will have a close look at the cable and attempt to run some serial numbers through google.

 

[Jtodd]

I believe the LX and SX has more to do with the wavelength used. SX being the shorter wave length associated with the transmission type (850 for multimode and 1300 for singlemode) and LX for the longer wave length (1310 for multimode and 1550 for singlemode). So you need to know more about the existing transievers.
You should most definetly find out what kind of fiber you have in the ground first (your existing transievers might tell you more). Post the part numbers you find here (if you haven't found them through google yet. Some one might recognize them as one or the other.


Justin T. Clausen
Physical Layer Implementation
California State University, Monterey Bay

 

[Grenage]

Thank you, Jtodd.

I managed to find out that the transceivers are "SuperStack II 100Base-FX Modules", which use Multimode cable only according to 3Com.

As both of the new switches are HP, their literature as to which modules can be used with which cable is very informative.

I decided on 2 of the SX modules.

Thanks again.