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DrDrew
That others may surf
Premium
join:2009-01-28
SoCal
kudos:17

4 edits
reply to jasontaylor

Re: [HD] Is Verizon lying about HD?

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downloadVerizon FIOS···ment.pdf 3,229,017 bytes
Verizon FIOS FTTP deployment PDF
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.

[edit] Added pics above, taken from the attached PDF.

--
If it's important, back it up... twice. Even 99.999% availability isn't enough sometimes.


ITALIAN926

join:2003-08-16
kudos:2
Nice response drew, but how could they increase to 1Ghz ? I thought thats where Moca lived, above 860Mhz?


More Fiber
Premium,MVM
join:2005-09-26
West Chester, PA
kudos:32
said by ITALIAN926:

I thought thats where Moca lived, above 860Mhz?

Indeed. Channel C4 is used for MOCA WAN. It is a 50Mhz frequency band from 875-1025Mhz.
--
There are 10 kinds of people in the world; those who understand binary and those who don't.


Zero

join:2009-07-01
Collegeville, PA
reply to ITALIAN926
You're right they can't because of MoCA, which is why they didn't start out with a 1GHz plant. Only options 1 and 3 are viable and only option 1 is mature enough to be implemented now.


DrDrew
That others may surf
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join:2009-01-28
SoCal
kudos:17

2 edits
reply to ITALIAN926
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MOCA has several bands. IF the provider is using up to 1 Ghz, they should probably use MOCA band D so it doesn't interfere.

Slide from this presentaion:
»www.mocalliance.org/CEDIA/presen···tion.pdf

Verizon didn't start with 1 Ghz because at the time they launched, the boxes weren't available to do 1 Ghz. It's possible now, but doesn't provide a huge benefit for the costs involved. Especially since all the 1 Ghz capable boxes also do MPEG4.


ITALIAN926

join:2003-08-16
kudos:2
Dr Drew, they couldnt do that because there are a BILLION 5-1000Mhz coax splitters in the field right now.


DrDrew
That others may surf
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join:2009-01-28
SoCal
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said by ITALIAN926:

Dr Drew, they couldnt do that because there are a BILLION 5-1000Mhz splitters right now in the field.

That 1000Mhz isn't a hard cut off.

The signal above 1000 Mhz still passes on the majority of 5-1000 Mhz splitters. They just aren't performance tested or rated for a known amount of loss above 1000 Mhz. MOCA equipment was designed with that in mind.
--
If it's important, back it up... twice. Even 99.999% availability isn't enough sometimes.