said by jasontaylor:
Ok, given the lack of a clear answer, perhaps I need to rephrase the q. Warning: this rephrasing is not for the math impaired.
1 HD channel is 4 mbps.
1 fiber optic cable is 26 Tbps.
1 terabit is 1048576 megabits.
Therefore, 26 Tbps / 4 mbps = 26 *1048576 / 4 =6815744 = about 7 million.
Therefore, 1 fiber optic cable can handle 7 million HD channels of data.
1 HD channel is a ~12-14 mpbs MPEG2 video stream. 1 SD channel is a ~3.8 mpbs MPEG2 video stream.
1 EIA 256 QAM, 6 Mhz wide, RF cable channel = ~38 mpbs usable data rate.
2-3 HD or 10 SD channels fit on a single 256 QAM RF cable channel.
Verizon FIOS fiber equipment carries a RF cable signal of 860 Mhz. This is on a separate light wave from the xPON data channels used for data.
860 Mhz = ~135 RF cable channels. These RF channels can be 256 QAM, 64 QAM, analog, or something else using a 6 Mhz wide analog carrier signal.
135 channels x 38 mbps = ~5.1 Tbps downstream broadcast data capacity.
135 QAM RF channels x 2 HD streams per QAM = 270 HD channels.
135 QAM RF channels x 3 HD streams per QAM = 405 HD channels.
Of course the actual number of HD channel is less due to the number of SD channels on the system.
To increase the number of channels carried, Verizon could:
1. Upgrade to MPEG4 or better. allows about double the number of HD channels per RF channel.
2. Upgrade RF bandwidth to 1 Ghz, allows for about 20 more RF channels and about 40-60 more HD channels.
3. Increase IPTV offerings beyond VOD, streaming channels only when requested. Possibly unlimited channels.
 Added pics above, taken from the attached PDF.--
If it's important, back it up... twice. Even 99.999% availability isn't enough sometimes.