The 40km optics will require optical attenuators for distances somewhere below 20km, possibly for 10km or less. They will certainly require optical attenuators for 4km distances. Chris -----Original Message----- From: Stephen Sprunk [mailto:stephen@sprunk.org] Sent: Thursday, December 13, 2007 1:52 PM To: Chris Cole; Mikael Abrahamsson Cc: North American Noise and Off-topic Gripes Subject: Re: IEEE 40GE & 100GE Thus spake "Chris Cole" <chris.cole@finisar.com>
The 40km/10km cost ratio is between 1.6x and 2x, depending on the source.
The 10km/4km cost ratio is between 1.15x and 1.3x, again depending on the source.
If those numbers translate into prices (not costs), then I'd prefer to see 40km and 4km optics, with no 10km optics. The important point is that the 40km optics neet to be able to handle 4.1km links with no attenuators, preferably without any human tuning at all. You only pay the extra capital cost once (if there even is any, due to more volume of fewer parts), but you pay labor and sparing over and over. S Stephen Sprunk "God does not play dice." --Albert Einstein CCIE #3723 "God is an inveterate gambler, and He throws the K5SSS dice at every possible opportunity." --Stephen Hawking