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What SFP module do I need?

Posted: Thu Apr 21, 2016 4:29 am
by rwrocket
fdfsd.jpg
The picture attached is of a cables only 10gig service we have with one of our upstream providers.

The information I have is that we need to connect to both ports 23 & 24 as one is TX and the other RX

This makes me inclined to think that it is single mode fiber

What I am not sure about is which SFP module I need on my router

probably be using something like a CCR1009 or CCR1036

I would like to get away with using only one SFP if possible.

Do I order a multimode SFP module and connect them with a SC to LC fiber patch lead?
OR do I need to buy a singlemode SFP module??? and if so do I then need two of them?

Logically in my head I think that a single multimode SFP connected to the two SC ports would work but I want to make sure before I order equipment

Rob.

Re: What SFP module do I need?

Posted: Thu Apr 21, 2016 4:54 am
by rcourtney
Singlemode and Multimode is how light internally travels through the glass strand.

On the outside of the yellow cables you should see some markings.
If you can post what is marked we can tell you if single or multi-mode.
What is on the other end of the bulkhead connector in your photo?

I will say there is a reason your provider is using what they are. Replacing your end
will not make it "work better". It is best to contact them.

For your info, light may be travel in both directions at the same time but usually requires
that it be on a different wavelengths. Special optical splitters allow both to be combined.

Re: What SFP module do I need?

Posted: Thu Apr 21, 2016 5:03 am
by rwrocket
The cable is LOOPED

so 23 goes into 24

I asked about this and was told that we need to use both ports (TX and RX) and it was looped for testing but we are free to remove the cable and insert our own.

I also found reference to duplex SMOF in the order for connection between demarc and our rack which makes me fairly sure this is single mode fiber.

So that being said...

I am planning to use one of these:
http://routerboard.com/Splus31DLC10D

it says it has dual LC, so couldn't I use a LC to SC patch lead to connect to both ports 23 & 24 and that should work?

Re: What SFP module do I need?

Posted: Thu Apr 21, 2016 8:26 am
by Mazutti
it says it has dual LC, so couldn't I use a LC to SC patch lead to connect to both ports 23 & 24 and that should work?
If the wavelenght used by your provider is the 1310nm (both TX/RX), and you´re within the 10km transceiver range, then yes, it should.

Re: What SFP module do I need?

Posted: Thu Apr 21, 2016 5:19 pm
by rcourtney
Ok since your order shows SMOF (Single Mode Optical Fiber) we are further along.

They are testing the light path with the same wavelength by looping and then measuring the loss for
round trip. Still good so far.

We still are guessing on the wavelength. Are you paying for dark strands? (they just connect two points together
no gear provided in between) Then you would order for both locations.

Normally they can provide you with SFP modules or a media converter for you if they are joining you to
a backbone service.

If dark strands, ask for path loss.

If the installer used the base per the wavelength used.
Blue is the 1310nm module
Yellow is the 1550nm module
Purple is the 1490nm module

So we might be correct ordering 1310nm modules.

Re: What SFP module do I need?

Posted: Fri Apr 22, 2016 9:22 am
by rwrocket
Thanks all

the 31DLC10D worked

Now I just need to find if there is a switch mikrotik make that has dual power and supports it

Re: What SFP module do I need?

Posted: Fri Apr 22, 2016 10:13 am
by pe1chl
Normally yellow cable = single mode fiber and orange cable = multimode fiber.
One or two connections is a different topic.
Two connections = separate fiber for each direction
One connection = same fiber used in two directions (different wavelength)

All of them must match or it will not work, there is no universal solution.