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New Member

How to select fiber?

Hi all,

I am still a man lack of experience now. My company want to implement fiber network and I need to choose what kind of fiber to use now. I just know 100FX and 1000Base-X, 1000Base-SX and they have different disance limit and speed. But is there any different that ( Beside the cost) ? And can I use FX interface in one end and SX in other end of a fiber? And it seem's that the 1000Base-x and 1000Base-SX are the same and have no difference? Also I hear that " The fiber has xx core " How to choose the "core" of the fiber? Thank You!

Best Regards

Teru Lei

3 ACCEPTED SOLUTIONS

Accepted Solutions

Re: How to select fiber?

When you are installing a Fiber backbone you should keep in mind that it must last for many years. It is not conservative to presume that future backbones will run on 10Gig or more.

Your Fiber cables must be able to transport these signals. With conventional 62,5/125 cable you won't get anywhere due to the pulse widening effect of the cable. It is better to pick a cable with a 50/125 core. This is generally known as single mode fiber. For example Avaya (Lucent) has a new 50/125 cable that is already guaranteed to deliver 10Gig. This is called: Lazrspeed.

SX and LX are just indicators for the output power of a module. This is related to the distance you want to cross (signal loss) and has not too much to do with the type of fiber cable that you use. It is OK to try and save on the transceivers but once your cabling is in place you need to rely on it for a long time. Do not try to save money on the quality of the fiber cable.

Regards,

Leo

New Member

Re: How to select fiber?

Dont worry so much on the hardware. Focus on the fiber. The laser can always be upgraded (and it willļ).

You must decide on multi mode or single mode fiber. This decision should be base upon:

1. The distance of the link.

2. The bandwidth needed (symbol rate).

3. The amount of cost the project can consume.

Here is a web page that will give you a little more info on the pros and cons of each.

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

New Member

Re: How to select fiber?

Distance is a major factor. Fiber size is also an issue. Distance will dictate fiber size. The following link will have all the information you need for GBIC specs.

http://www.cisco.com/en/US/products/hw/routers/ps314/prod_module_configuration_guide09186a008007c781.html

A company called MRV also sells a GBIC Multimode Extender.

Multimode fiber comes in two flavors 62.5/125 micron very common in US at least, and 50/125 micron (international standard)

Single mode fiber also comes in two flavors 9 micron and 8 micron.

By experience run about double the amount of strands that you think you will need. Later on other applications will come up that will require connectivity.

4 REPLIES

Re: How to select fiber?

When you are installing a Fiber backbone you should keep in mind that it must last for many years. It is not conservative to presume that future backbones will run on 10Gig or more.

Your Fiber cables must be able to transport these signals. With conventional 62,5/125 cable you won't get anywhere due to the pulse widening effect of the cable. It is better to pick a cable with a 50/125 core. This is generally known as single mode fiber. For example Avaya (Lucent) has a new 50/125 cable that is already guaranteed to deliver 10Gig. This is called: Lazrspeed.

SX and LX are just indicators for the output power of a module. This is related to the distance you want to cross (signal loss) and has not too much to do with the type of fiber cable that you use. It is OK to try and save on the transceivers but once your cabling is in place you need to rely on it for a long time. Do not try to save money on the quality of the fiber cable.

Regards,

Leo

New Member

Re: How to select fiber?

Dont worry so much on the hardware. Focus on the fiber. The laser can always be upgraded (and it willļ).

You must decide on multi mode or single mode fiber. This decision should be base upon:

1. The distance of the link.

2. The bandwidth needed (symbol rate).

3. The amount of cost the project can consume.

Here is a web page that will give you a little more info on the pros and cons of each.

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

New Member

Re: How to select fiber?

Distance is a major factor. Fiber size is also an issue. Distance will dictate fiber size. The following link will have all the information you need for GBIC specs.

http://www.cisco.com/en/US/products/hw/routers/ps314/prod_module_configuration_guide09186a008007c781.html

A company called MRV also sells a GBIC Multimode Extender.

Multimode fiber comes in two flavors 62.5/125 micron very common in US at least, and 50/125 micron (international standard)

Single mode fiber also comes in two flavors 9 micron and 8 micron.

By experience run about double the amount of strands that you think you will need. Later on other applications will come up that will require connectivity.

New Member

Re: How to select fiber?

Thanks all of you. The statement and web links give me enough knowledge.

Best Regards

Teru Lei

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