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Fiber: single or multimode?

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I'm new to fiber, never used it.

 

I'm installing a IP Camera system in my storage facility. The fiber has to be about 450 - 500 foot distance. The system will at most have 64 cameras (one day) but for now 6. I know the best way to send the data back to the server is via fiber but I've never used it. Some installers are recommending single mode while others are recommending multi mode. I know multi is less expensive and more useful in short distance while single mode is more expensive but can handle longer runs (excess of 2km which i don't need). Which should I be installing.

 

Also some installers are recommend LC connectors on each end while others are recommending SC connectors. I'm lost and don't want to end up with a system I can't use. Any input would be great, thank you

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I'm new to fiber, never used it.

 

I'm installing a IP Camera system in my storage facility. The fiber has to be about 450 - 500 foot distance. The system will at most have 64 cameras (one day) but for now 6. I know the best way to send the data back to the server is via fiber but I've never used it. Some installers are recommending single mode while others are recommending multi mode. I know multi is less expensive and more useful in short distance while single mode is more expensive but can handle longer runs (excess of 2km which i don't need). Which should I be installing.

 

Also some installers are recommend LC connectors on each end while others are recommending SC connectors. I'm lost and don't want to end up with a system I can't use. Any input would be great, thank you

 

You are starting at the wrong end of the issue.

 

The factors you should be considering are the cable distance and the bandwidth required (now and in the future).

 

This determines the fibre type (single mode or multi mode) and finally the end kit you select indictes which connector you need following consideration of first first two requirements.

 

Ilkie

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As far as I know 64 cameras at 15fps, 800x600 equates to 360mbps. A 1GB/s Ethernet would work but the distance is over 100 meters so i would have to repeat it and I rather not. So the length is 450-500 feet and the bandwidth needed is 360mbps. I'm sure we have to take into account other factors like network hand shaking and other administrative traffic but I believe any type of fiber will handle my needs easily.

 

I just need to make sure I know why some installers are recommending single mode rather than multi mode

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As far as I know 64 cameras at 15fps, 800x600 equates to 360mbps. A 1GB/s Ethernet would work but the distance is over 100 meters so i would have to repeat it and I rather not. So the length is 450-500 feet and the bandwidth needed is 360mbps. I'm sure we have to take into account other factors like network hand shaking and other administrative traffic but I believe any type of fiber will handle my needs easily.

 

I just need to make sure I know why some installers are recommending single mode rather than multi mode

 

You second time forget about fiber cable bandwidth

Read this:

http://www.arcelect.com/Calculating_fiber_loss_and_distance.pdf

http://en.wikipedia.org/wiki/Gigabit_Ethernet

 

So, if you have 2 km distance, 1Gbps link will not work with multimode cable, or you will need specific expensive gigabit multimode converters....

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As far as I know 64 cameras at 15fps, 800x600 equates to 360mbps. A 1GB/s Ethernet would work but the distance is over 100 meters so i would have to repeat it and I rather not. So the length is 450-500 feet and the bandwidth needed is 360mbps. I'm sure we have to take into account other factors like network hand shaking and other administrative traffic but I believe any type of fiber will handle my needs easily.

 

I just need to make sure I know why some installers are recommending single mode rather than multi mode

 

You second time forget about fiber cable bandwidth

Read this:

http://www.arcelect.com/Calculating_fiber_loss_and_distance.pdf

http://en.wikipedia.org/wiki/Gigabit_Ethernet

 

So, if you have 2 km distance, 1Gbps link will not work with multimode cable, or you will need specific expensive gigabit multimode converters....

 

That means that since my distance is less than 500 feet Multimode will work, right?

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As far as I know 64 cameras at 15fps, 800x600 equates to 360mbps. A 1GB/s Ethernet would work but the distance is over 100 meters so i would have to repeat it and I rather not. So the length is 450-500 feet and the bandwidth needed is 360mbps. I'm sure we have to take into account other factors like network hand shaking and other administrative traffic but I believe any type of fiber will handle my needs easily.

 

I just need to make sure I know why some installers are recommending single mode rather than multi mode

 

You second time forget about fiber cable bandwidth

Read this:

http://www.arcelect.com/Calculating_fiber_loss_and_distance.pdf

http://en.wikipedia.org/wiki/Gigabit_Ethernet

 

So, if you have 2 km distance, 1Gbps link will not work with multimode cable, or you will need specific expensive gigabit multimode converters....

 

That means that since my distance is less than 500 feet Multimode will work, right?

 

Yes, but also think about the future. If in a couple of years you will upgrade to megapixel and/or install a lot more cameras, then Gigabit Ethernet will not be sufficient bandwidth. The move to 10 Gigabit Ethernet transmission will require single mode fibre.

 

To simplify the next stage, choose your kit and check the optical budget of the kit you are going to use. Providing the planned installed fibre is under the stated budget allowing for ageing, the system should work.

 

Ilkie

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I forgot to ask a question. How should the multimode be terminated on each end? Some say SC while others say LC, what do you recommend?

 

Also I need to buy a network switch. It must be able to except fiber(above), withstand extreme temperatures (It will be in a storage unit in new england), and have at least 8 ports for 100/1000 Ethernet (cat6) connections. I would love if it had another minimum 6 ports at 10/100 with POE but I think i may need another switch for only the POE. Any recommendations on the product?

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fiber connectors are simply a matter of what inputs you have on your switches or adaptors. Make sure you get 50 micron fiber the 62.5 stuff will not support 1 gig. Hopefully your installer knows that the 50 micron stuff requires connectors that are also 50 micron. I think the 50 micron connectors are blue. I would also install some spare fibre when you do this if you need 6 strand get twelve If you leave the spares unterminated it does not add much to the cost.

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fiber connectors are simply a matter of what inputs you have on your switches or adaptors. Make sure you get 50 micron fiber the 62.5 stuff will not support 1 gig. Hopefully your installer knows that the 50 micron stuff requires connectors that are also 50 micron. I think the 50 micron connectors are blue. I would also install some spare fibre when you do this if you need 6 strand get twelve If you leave the spares unterminated it does not add much to the cost.

 

 

Thanks Jeromephone

 

I would have been in a world of trouble if i'd gone with the 62.5. This leads me to my next questions...why do i need even 6 strands instead? i thought a single strand of fiber would do the job. Once again I've never used fiber before so any information would help. So for now i'm going with single strand multimode at 50 microns unless you can convince me I need otherwise.

 

Thanks again guys, this is a huge help and it is appreciated

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It all comes down to money. The labor and expense of the install are a big part of the overall cost. Also if you ever want to run data (IP Cameras) Ethernet etc you need two strands. If a single fiber fails and you have another set already terminated you may be able to plug that into your switch and keep going. Check out the fiber prices to see the differences in the various fiber counts.

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It all comes down to money. The labor and expense of the install are a big part of the overall cost. Also if you ever want to run data (IP Cameras) Ethernet etc you need two strands. If a single fiber fails and you have another set already terminated you may be able to plug that into your switch and keep going. Check out the fiber prices to see the differences in the various fiber counts.

 

I mostly agree with your comments with a couple of small points.

 

50/125 fibre will offer better performance but it rarely used in the IT industry.

 

You will more likely find IT networking kit that uses 62.5/125 fibre.

 

There is no advantage in installing 50/125 fibre if the end kit is offers 62.5/125 connection.

 

Options are sometimes available for signly fibre transmission but most with use two fibre cores (Tx and RX). Single fibre equipment will be very much more expensive so as the reccomendation is to install 4 or 6 fibre cable (good advice), a two fibre option will be more cost effective.

 

I would suggest that you now identify the equipement you wish to use and this will confirm the technical details you need to specify regarding the fibre cable type and connectors.

 

Ilkie

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We have not installed anything other than 50 micron in the past couple of years and it s almost always for data. I am not sure as we don't get into the switches and such much but i think it is like installing cat6 cable and using a 10/100 switch you still only get the 10/100 but if you switch hardware you can go to 1000. Again I am not sure but a lc or sc connector sized for 50 micron will work with any switch that takes sc or LC it just will only do what the switch or media converter is rated at. I have asked my suppliers this question and I would like to hear if there is a different answer. I have had the experirnce of installing the wrong connectors ie 62.5 on 50 micron fiber very costly as it took quite a while to figure what was going on.

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So I think I know what I'm going to get. I need a 50 micron fiber cable that is multimode and has at least 4 strands.

 

I still haven't decided on the connectors yet but I see most people are using LC.

 

I need to pull this cable throw 450 feet of underground conduits. The pull cord was put in during installation so I believe it will be easier to do. I'm going to use a $&!t load of cable grease and do my best to pull this thing through while someone feeds it in.

 

Any ideas where I can get this cable from? Links would be appreciated. I'm also assuming about a $1 a foot is a good price and more than $1.70 is over priced

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fiber connectors are simply a matter of what inputs you have on your switches or adaptors. Make sure you get 50 micron fiber the 62.5 stuff will not support 1 gig. Hopefully your installer knows that the 50 micron stuff requires connectors that are also 50 micron. I think the 50 micron connectors are blue. I would also install some spare fibre when you do this if you need 6 strand get twelve If you leave the spares unterminated it does not add much to the cost.

 

 

How can I tell if a switch will support the 50 micron cable? Most installers are telling me I don't need it. What bandwidth will the 62.5 micron cable support over 450 feet? I used an IP calculator to figure out the worst case scenario if i setup 50 cameras at 15fps using 1200x1600 and it says I need 322 MB/s (http://www.video-insight.com/Support/Tools/IP-Bandwidth-Calculator.aspx)

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After looking at the following document I see that I can easily achieve 1Gb/s using 62.5/125 as long as i don't pass 220Meters (721 feet). This distance i am covering is 450 Feet so i will be going with the 62.5/125 because most equipment supports this type of cable.

 

I encourage any arguments that oppose my decision as I am very new to this.

 

http://www.imcnetworks.com/Adocs/Support/to-fibercaldist.pdf

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I would check the mfg website and talk to a rep. I think thats how I got the info a few months ago when I was going through the same drill. The 50 micron may be overkill but who knows what else might be running over the fiber it seems that everything is IP anymore. I am a big believer in overbuilding a bit. i know of a few buildings that are not that old that insisted on cat 3 wire because they could save so much on install costs. 4 years later they did it all over again.

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Guys,

 

Multimode went by the wayside years ago. I haven't installed multimode since 2007 and that's because I had a RAD serial to fibre multiplexor to support. As far as normal run of the mill IP gear goes no-one looks seriously at multimode. Single mode and multi mode cost around the same, Cost of burying fibre is usually the main expence. The ends supports can be more expensive but not as expensive as having to change from multi to single when no one supports it any more. There was a world wide shortage of single mode around 2005 that was because everyone was replacing their multi mode.

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I forgot to ask a question. How should the multimode be terminated on each end? Some say SC while others say LC, what do you recommend?

 

Also I need to buy a network switch. It must be able to except fiber(above), withstand extreme temperatures (It will be in a storage unit in new england), and have at least 8 ports for 100/1000 Ethernet (cat6) connections. I would love if it had another minimum 6 ports at 10/100 with POE but I think i may need another switch for only the POE. Any recommendations on the product?

 

Netgear has a 24 Port POE 10/1000 with GBIC Slots for fiber for around $700.00, GBIC's around $300.00

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Since when will 62.5 not support 1Gbps?

 

You don't need no fancy switches that accept SFP modules for fiber. Get some inexpensive media converters. 1Gbps less than 200 meters will be about 100 bucks for the pair.

 

Single mode would have issues on that short of a distance and would probably require attenuators to reduce the signal because it would be too hot.

 

There are 2 light waves used on Multimode. 800 nanometers for less than 200 Meters and 1300 Nanometers for less than 2000 meters.

 

Most of the inexpensive media converters are either SC or ST connectors.

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Guys,

 

Multimode went by the wayside years ago. I haven't installed multimode since 2007 and that's because I had a RAD serial to fibre multiplexor to support. As far as normal run of the mill IP gear goes no-one looks seriously at multimode. Single mode and multi mode cost around the same, Cost of burying fibre is usually the main expence. The ends supports can be more expensive but not as expensive as having to change from multi to single when no one supports it any more. There was a world wide shortage of single mode around 2005 that was because everyone was replacing their multi mode.

 

 

Multimode is going no where!

We put it in every day.

Government projects where money is no object are migrating to 50 micron and 50 micron laser optimized but short runs will be multimedia for a long time to come.

 

As a general rule Multimode is used from MDF to IDF closets and short run building to building.

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Since when will 62.5 not support 1Gbps?

 

You don't need no fancy switches that accept SFP modules for fiber. Get some inexpensive media converters. 1Gbps less than 200 meters will be about 100 bucks for the pair.

 

Single mode would have issues on that short of a distance and would probably require attenuators to reduce the signal because it would be too hot.

 

There are 2 light waves used on Multimode. 800 nanometers for less than 200 Meters and 1300 Nanometers for less than 2000 meters.

 

Most of the inexpensive media converters are either SC or ST connectors.

 

You can get 1G SFP mods for around $100 a pair.

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