[c-nsp] No Link between SFP-10G-LRM and X2-10GB-LX4?

[Jeroen van Ingen]

Mack,

On Mon, 2011-10-10 at 14:59 -0700, Mack McBride wrote:
> The LRM looks like the way to go for you if you are limited by SFP+ as
> the Andrew pointed out.

Only I'm not the OP :). Andrew is correct though, LX4 doesn't seem
available in SFP+.

> The Cisco spec is for 220M at 500MHz fiber on LRM.
> Basically with dispersion you will get shorter error free distance so
> although the LX4 is only listed for 500MHz it will work at lower modal BW.
> It just shortens the range.  Same is true for the LRM.
> It will work at lower modal BW but you get shorter ranges.
> You are probably close to the limit with 160M and 200MHz modal BW.
> And I would say you are over the 'rated' limit.
> For reference the 50 micro with 400MHz modal BW the rated limit is 100M.

Well, actually I'm using SFP+ LRM transceivers from HP (J9152A) which
*are* spec'd for up to 220 meters on 160MHz modal BW MMF. But we're
drifting off-topic here :). Thanks for all your thoughts though.


Regards,

Jeroen van Ingen
ICT Service Centre
University of Twente, P.O.Box 217, 7500 AE Enschede, The Netherlands