Cisco HFR

Interestingly the OC-768 card has a max transmit power of 5dB and is
short-range optics only.

The 300-pin-MSA for OC768 has a SR spec of TX 0..+3dBm, RX min -5dBm.
Dispersion is max 40ps/nm.

As far as I know there are no 2R or 3R
regeneration solutions for long haul 40Gb/s circuits, nor are there any
DWDM systems that can do 8, 16 or 32 40Gb/s wavelengths.

Incorrect. There are transponders that put a 40G signal in a 10G DWDM
optical system. (You have to move a step up from morse code to make the
side-bands fit..) And they atleast run in 80 chanel systems.

-P

What is the range of this, how often do you need to amplify and regen the
40G signal compared to 10G? Can 10G optical amplifiers be used?