MM LC SFP's for ST to LC jumper cable

[hmc250000]

Does anyone know what SFP's will work with the cable specs in the attached files? I would think at the least they'll need to be Multi mode. What else do I need to be mindful of so I can ensure they are fully compatible with the cables? Thanks.

[Marvin Rhoads]

Both the packages you shared are multimode cables with LC at one end (for the SFP) and ST at the other end (typically for patch panels with ST connector types).

There are literally dozens of Cisco SFPs that would work with those cables. More important is what type of equipment you are plugging the SFPs into.

Working backwards from the $10 patch cable instead of from the $100s transceiver or $1000s equipment is an unusual question outside an academic (i.e. school assignment) scenario.

[hmc250000]

The link between both our IDF's is Fiber with the ST plugs. We use the ST to LC jumper cables to connect our switches to the fiber link. We see light in one of the cables but get no connection when we connected it to the switches. I have used Multimode SFP's (will get the exact model# tomorrow) on both sides. Is there a difference between the LX and SX SFP's? 

[Marvin Rhoads]

There's a significant difference:

LX SFPs use coherent light (laser) and thus require single mode cabling end to end.

SX SFPs use non-coherent light (LED) and require multimode.

A given link has to have only one type of SFP. That is, an LX-SX pair cannot ever establish a link.

http://www.cables-solutions.com/basics-1000base-sx-1000base-lx-sfp.html

[hmc250000]

Thank you. Got it working with a 1000BaseLX SFP on one end and a 1000BaseLX SFP (GLC-LH-SM) on the other end. However I'm baffled why it works because the cables are multi mode as in the pictures in the previous post. I'm guessing the run must actually be single mode. The cable guy told me he got the multi mode number specs from the fiber cable jack.

[Marvin Rhoads]

The bag labels you shared are for multimode jumpers. The actual cable type should be printed in very small letters every so often along the length of the jumper.

You can sometimes get single mode to "punch through" multimode over very short distances. It's never a good practice to do so however as the signal will be significantly degraded.

[amikat]

Hi,

In addition to single-mode fiber you can also use multimode fiber to connect 1000BaseLX SFPs if the fiber type is OM3 or OM4 (so called laser-optimized). The cables from your original post are of OM1 type however so you would need mode-conditioning patchcords should you decide to use these for the 1000BaseLX SFP.

Best regards,

Antonin