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We have got some old 62.5um single-mode fiber links in our building. Network people told me, that Cisco 10GBASE-LRM with Cisco mode conditioning patch cables works fine on those cables and provides a stable 10GBit link.

Now we need to add a new direct link between servers over the same cable, and were considering Intel cards with Intel transceivers. Apparently 10GBASE-SR should not work over this cable (total link length is over 200m). Do I understand correctly that 10GBASE-LR transceivers should work just fine with these cable infrastructure? Which kind of patch cables should we use, single-mode patch cables, multi-mode patch cables, or mode conditioning patch cables?

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LR connections are single mode. You'll need mode conditioning patch cables on both sides but likely a different type than was in use for your LRM (which wants multimode, but with a smaller core).

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LR likely won't work at all over this fiber. Needs to be single mode end to end. – Dan Pritts Aug 18 '12 at 21:56… - the application in question can use the cited conditioning cables... this is what they're for. – rnxrx Aug 19 '12 at 1:38
Learn something new every day. Mode conditioning cables have other uses, FYI - in particular they are useful with 10GBASE-LRM. It's spec'd to work over 62.5 micron (old style) multimode; but it can go much longer distances over that fiber with the mode conditioning cable. – Dan Pritts Aug 23 '12 at 17:54

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