Range using single-mode SFPs across multi-mode fiber

Keegan Holley keegan.holley at sungard.com
Wed Dec 14 21:50:10 CST 2011


I stand corrected, but I haven't dealt much with 100BASE-FX.  I was just
talking in terms of 1G/10G.


2011/12/14 Mark Foster <blakjak at blakjak.net>

>  On 15/12/11 16:38, Keegan Holley wrote:
>
> 2011/12/14 oliver rothschild <orothschild at gmail.com> <orothschild at gmail.com>
>
>  Thanks to all who responded to my clumsy first question (both on
> matters of etiquette and technology). The group I work with (we are a
> small project acting as a last mile provider) was in the midst of
> deploying this solution when I posed the question. We put the single
> mode Juniper SFPs (LX) on to a run of approximately 1670 meters.
>
>
>  How did you end up with a MM run this long?  SX optics are only rated at
> 500 meters at best.  Even with mode conditioning jumpers more the 1km is a
> risk.  I'm glad it held up during testing though.  Just out of curiosity
> did you purchase dark from a provider?  Is it inside of a building?
>
>
> Um.. check that.
>
> https://en.wikipedia.org/wiki/Multi-mode_optical_fiber
>
> "Typical transmission speed and distance limits are 100 Mbit/s for
> distances up to 2 km (100BASE-FX<https://en.wikipedia.org/wiki/100BASE-FX>),
> 1 Gbit/s to 220–550 m (1000BASE-SX<https://en.wikipedia.org/wiki/1000BASE-SX>),
> and 10 Gbit/s to 300 m (10GBASE-SR<https://en.wikipedia.org/wiki/10_Gigabit_Ethernet#10GBASE-SR>
> )."
>
> The old OM1 installations I used to work on started out as 10Mbit hubbed
> ethernet links and on the odd occasion would run out to close to 2km within
> a campus.  They were progressively upgraded with the flow of:
>
> 10FX on 3Com Linkbuilder Kit
> 100FX on 3Com Corebuilder Kit and Allied Telesyn 100FX Media converters
> 1000SX on a variety of 3Com, Nortel and Cisco kit out to ~220m
> 1000LX via Mode-Conditioning out to ~900-1000m.
>
> The OM1 only got retired when the distance was >900m or there was budget
> to put new fibre on the run, in which case we ran SMF and rigged LX drivers.
>
> Mark.
>
>
>
>
>


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