Hi all, I am new to fiber cabling. I have some basic questions. Been reading about multimode 50/125 plenum cables. The 10G cost more then non-10G. Can I use the 10G on 1G speed ? (without any special attenuators, etc.). My thought was to cable two buildings using the 10G 50/125 and currently use 1GB media converters at each end. Then later when more speed is needed/bandwidth I can get 10GB converters. Any thoughts on this ??
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10G vs 1G mulitmode 1
- Thread starter bithead9
- Start date
mikeydidit
IS-IT--Management
My thoughts are, if you run single mode fiber now, you will about as future proof as you can be. We began our network on 62.5 MM fiber and its still in place but we are also adding SM to all of our closets.
Also as of now, the only limitations on SM fiber is the technology to make it do more. Not a better grade of fiber.
"A people that values its privileges above its principles soon loses both."
- Dwight D. Eisenhower (1890-1969), Inaugural Address, January 20, 1953
For the best response to a question, read faq690-6594
Also as of now, the only limitations on SM fiber is the technology to make it do more. Not a better grade of fiber.
"A people that values its privileges above its principles soon loses both."
- Dwight D. Eisenhower (1890-1969), Inaugural Address, January 20, 1953
For the best response to a question, read faq690-6594
There are now 3 "standards" for fiber. 2 are multi-mode and 1 is singlemode. singlemode has always been more expensive in terms of the equipment that connects to it. (It uses 1310 and 1550 nm laser wavelengths.) Rules of thumb: the thinner the fiber, the longer you can send a signal. Hence singlemode fiber size is 8 microns. If you are planning on a 10Gig backbone at any time, I would strongly recommend installing singlemode fiber. Multimode, which uses less expensive electroncs, has recently changed a bit. The "new" standard is 50 micron ("laser enhanced") and the older 62.5 micron. If you are installing new, install a hybrid cable that contains both singlemode and 50 micron multimode (this cover you for whatever you need to do, now and later). You only need to remember that 50 micron mm fiber has to be all 50 micron, from end to end. (you cant have a 62.5 patch cable anywhere in your run) 50 micron will work with all existing 1Gb multimode (usually either an 850 nm laser or LED transmission). 10Gig will run over 50 micron fiber for shorter distances (UP to 300 meters) with cheaper transceivers (electronics). If you are going with 10Gig from scratch, you may want to just use all singlemode. The 10Gig-LR will shoot down Singlemode fiber up to 10 KM! This way you will have reliable transmissions and distance wont be an issue. Singlemode, 10Gig with some very expensive electronics (laser hardware) can shoot up to 70 KM.
So, new install, install hybrid 50Micron/SM combo cables, then you are covered for all conditions now and for the future.
So, new install, install hybrid 50Micron/SM combo cables, then you are covered for all conditions now and for the future.
you can run 10G on 62.5 as long as the run is under 720' feet
Allan Goodson
Estimator
3D Datacom, Inc.
Allan Goodson
Estimator
3D Datacom, Inc.
- Thread starter
- #6
Thanks to everyone for the replies. One last thing. I thought that with short runs of singlemode you need attenuators (the light is too strong?) - whereas multimode usually does not have that issue. I like the idea of a hyrind (or simply sm) but want to avoid complications.
at what point (with sm) do you need attenuators? Of course cost is an issue for this job as it is a elementary school campus. If tranceivcers for singlemode are very high cost I will probably HAVE to go with the mm. There will be 3 pairs of tranceivers connecting 4 buildings. All under 1800 feet.
at what point (with sm) do you need attenuators? Of course cost is an issue for this job as it is a elementary school campus. If tranceivcers for singlemode are very high cost I will probably HAVE to go with the mm. There will be 3 pairs of tranceivers connecting 4 buildings. All under 1800 feet.
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1
- #7
The need for attenuators will depend on the output strength and receive sensitivity of your transceivers. Gotta read the spec on them and do the math (output - cable loss = receive specs).
If you're talking just media converters at either end, SM aren't that much more expensive than multimode, and since SM glass is cheeper than laser opt. 50mn (there is non-laser opt which isn't 10G) it may actually be more cost effective to go with SM in the first place.
If you've got the budget, I'd put in both SM and LOMM then use what ever electronics fit you budget right now.
Justin T. Clausen
Physical Layer Implementation
California State University, Monterey Bay
If you're talking just media converters at either end, SM aren't that much more expensive than multimode, and since SM glass is cheeper than laser opt. 50mn (there is non-laser opt which isn't 10G) it may actually be more cost effective to go with SM in the first place.
If you've got the budget, I'd put in both SM and LOMM then use what ever electronics fit you budget right now.
Justin T. Clausen
Physical Layer Implementation
California State University, Monterey Bay
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