Yes, but in very specific cases such as older ZD, NZD fiber and SMF with 20 or more lambdas (at 2.5 Gbps or less) and with Ultra long haul and ultra DWDM 600 - 800 miles, 25 nm spacing and fiber with too high a water vapor content and/or higher impurities in the fiber. If you have less than optimum fiber you need the additional optics and electronics to make it perform. So my question is the same as the underliying one in your presentation which for Scott is what are you trying to do and there are several ways to reduce the cost or if you need the super neat, highest speed, longest run stuff you will pay for it. Side note, I liked your two presentations. john ________________________________________ From: Alex Pilosov [alex@pilosoft.com] Sent: Friday, April 25, 2008 1:58 PM To: John Lee Cc: Scott E. MacKenzie; NANOG Subject: RE: [NANOG] DWDM More Details On Fri, 25 Apr 2008, John Lee wrote:
In your talk, I agree that the CAN with your CWDM is not that expensive but you also mention that the tighter DWDM with long haul optics is expensive ie "Everybody knows how to do (active) xWDM by giving a lot of money to (insert vendor of choice]:"
When you talk about the tighter itu spacing for "real" DWDM and the lasers with fiber that can handle the power, jitter, chromatic dispersion et al. the optics you mention will not handle that.
We have all duct taped optical systems on campus for the lab "and across the state of Georgia" see the Peach Net map.
What is the largest number of lambdas you have actually run on a single fiber with your duct tape system and how bad was the optical cross talk? I'd be curious to ask reverse question, did anyone *have* real problems deploying duct tape systems, or power jitter chromatic dispersion is vendor mumbo jumbo designed to make you buy their gear?
(within the distance limits spec'd, 80km dwdm etc) -alex _______________________________________________ NANOG mailing list NANOG@nanog.org http://mailman.nanog.org/mailman/listinfo/nanog