 
Kfedka
Premium
join:2005-05-06
Spokane, WA | Not enough bandwidth? Why not enough bandwidth, enless there are 10 tv's in the house watching hd channels. | |
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 | GHz
join:2002-01-02
Needham, MA
| Re: Not enough bandwidth? I'm no cable expert, but it doesn't matter how many TVs are watching, it's a media transport limitation. A cable system works like a giant hub, and all cable channels are broadcast to all end-users, regardless of whether they are watching them or not. So you're already at-capacity, the only way to add more channels is to free up bandwidth by dropping unused channels. What they are proposing here is a switched media system, where not all channels are broadcast at the same time... channels are essentially on-demand, which means you can add as many channels as you like.
Someone correct me if I'm way off-base :P | |
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Alpine
Premium
join:2000-01-11
Atlanta, GA | Re: Not enough bandwidth? I think you hit it on the head...
Adam | |
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cdru
Go Colts
Premium,MVM
join:2003-05-14
Fort Wayne, IN
| Essentially it's VoD at the node level. If anyone on a particular node wants say ESPN, then it gets broadcasted. If no one wants to watch QVC, then that bandwidth is not allocated for that channel.
Say you have 100 different channels and a node has 100 different receivers. At worst, you really are no worse off (network overhead aside) as all 100 stations would still be broadcasted. But if 1 or more of those receivers watched the same channel as another, you'd start saving bandwidth for other uses.
To make full use of this though nodes need be smaller. The larger the node you are on, the more likely the number of distinct channels increase. It's more likely a node of 500 customers would be watching more channels then a node of 100 customers.
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Go Colts | |
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thender2
Glamour Profession
Premium
join:2004-05-16
Staten Island, NY
| A 1080i channel with equal quality to OTA tv is 17 mbps.
This is real quality - not directv, overcompressed-because-satelite-bandwidth-sucks bandwidth.
Three TVs is 51 mbps.. that's a lot. Cable can't handle this at peak hours. Looking at all the prior posts in the front page news, most major cable ISPs can't even handle internet, much less more HDTV.
I forsee a day where your TV shows "you have exceeded your monthly limit as specified by the fair use portion of the TOS" instead of 24 at 9 PM on Monday night.
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The Problem With Music.
Our Rationale
Time to rewrite the DMCA. | |
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| | Enlightener
join:2006-01-28
Cedar Park, TX
 ·AT&T U-Verse
| Re: Not enough bandwidth? Cable is multicast not point to point like IPTV. It's not three people watching the same channel that causes the bandwidth usage, it's three people watching different channels that causes it. With SDV the slots are allocated as people ask for the channel.
I actually see SDV as a pretty good solution. It eliminates 50% of the bandwidth waste. Combine that with DOCSIS 3.0 providing more bandwith and ultimatly putting less people on a node and I think cable has bandwidth for years to come. The question is: are those things cost competive compared to just going pure fiber. | |
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| | valuepac0
join:2001-05-30
Santa Monica, CA
| said by thender2  :A 1080i channel with equal quality to OTA tv is 17 mbps. This is real quality - not directv, over compressed-because-satelite-bandwidth-sucks bandwidth. Three TVs is 51 mbps.. that's a lot. Cable can't handle this at peak hours. Looking at all the prior posts in the front page news, most major cable ISPs can't even handle internet, much less more HDTV. I forsee a day where your TV shows "you have exceeded your monthly limit as specified by the fair use portion of the TOS" instead of 24 at 9 PM on Monday night. 1080i signal = 19.1 mbits, 720p signal = 15.3 mbits. Each Analog channel takes 6 MHz of freq, most cable networks in the US are 550 MHz, 750 MHz or 960 MHz. You can fit 6-8 digital channel or 2 HD channel in the same spot as 1 analog channel… I believe with QAM256 you are able to get 38.1 mbits per 6 mhz…
SDV will work the same way that current cable system works on the stand point on the node it doesn’t matter if 1 person or a 100 are watching. What SDV does is allocate frequencies to certain channels dynamically, much like DHCP work for a cable modem or your home network. So for instance let’s say I'm the first person to watch DiscoveryHD in my neighborhood, you tune to the channel on your cable box, the box sends out a signal to the node saying I want to watch discoveryhd. It checks to make sure I pay for the channel, and then allocates a frequency to that channel. Now let’s say Fred, 8 house down, also wants to watch discoveryhd at the same time as I am watching it. He tune to the channel on the cable box, the box sends out a signal to the node saying I want to watch discoveryhd. It checks to make sure I pay for the channel, and then sees that someone else is watching it on the node and what frequency is allocated to that channel on the node, it then uses the same frequency and tunes in without using anymore bandwidth. So doesn’t matter if 1 or 100 are watching it, or if you have the same channel on 10 TVs in your house. | |
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thender2
Glamour Profession
Premium
join:2004-05-16
Staten Island, NY |  Re: Not enough bandwidth?
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join:2005-04-13
Denton, TX | Very nice explanation! So if this is true, it would actually be good if on one node 1,000 people were watching "24" or the Super Bowl because, essentially, it would only be like allocating a frequency for 1 person? | |
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linflas
join:1999-08-18
Manassas, VA
·Verizon FIOS
| So the problem really is the current situation where you have digital and analog being delivered over the same cable? From what you posted it seems to me this problem self corrects if the digital switchover takes place in February 2009 as currently scheduled. | |
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madisonjar
join:2005-08-26 | Re: I hope... Directv with the New Mpeg4 has been compared to OTA and found to be almost identical with very comparable quality in many areas.....while they did DOWNREZ (notice no HD LITE) with Mpeg2, Mpeg4 seems to be full Blow HD. | |
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Neyland
join:2003-02-04
USA | Re: I hope... Regardless of the MPEG compression, do they lower either the bit rate or the resolution below 1920x1080? | |
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dvd536
as Mr. Pink as they come
Premium
join:2001-04-27
Phoenix, AZ
| Re: I hope... said by Neyland :Regardless of the MPEG compression, do they lower either the bit rate or the resolution below 1920x1080? All satellite does.
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You can never be too rich, too thin or have too much Bandwidth | |
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scooby
Premium
join:2001-05-01
Schaumburg, IL
| I don't know if anyone has found a way to find out the resolution or bitrate being used on the mpeg4 locals. From what I have seen they are close to OTA but not like what Comcast offers. Untouched, uncompressed, no downrez'ing. Passed to the customer as they are received.
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SunRocket - You get what you pay for! | |
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toadlife
Premium
join:2004-05-03
Lemoore, CA
 ·AT&T Yahoo
| Re: I hope... said by scooby :I don't know if anyone has found a way to find out the resolution or bitrate being used on the mpeg4 locals. From what I have seen they are close to OTA but not like what Comcast offers. Untouched, uncompressed, no downrez'ing. Passed to the customer as they are received. I just switched from Comcast, who only offers plain analog cable in my town, to DirecTV.
DirecTV does downsize their 1080im channels quite a bit, but for the most part the channels look fantastic.
I can tell that they downsize because my TV has a zoom mode that you can choose the native resolution of the channel. When I select this, the channel doesn't fill up the whole screen.
The resolution of my TV is 1320x768, so I could take a photo of the TV with an HD channel on and calculate the size using a paint program. My best guess would be they are resizing them down to something like 1280x640.
yeah, I guess it sucks that they downsize, but I'm only paying 20 more dollars a month than I did for Comcast's crappy analog service and get about 40 more channels - and the HD channels look nice to me.
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Break yourself from the Windows admin nipple...
»nonadmin.editme.com | |
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Mr anon
@il.us
| What about... the digital errors I'm seeing, they are comming back and getting worse than the were before. I thought we'd escape it a few more years after we went back to all analog but eh.
The more tI thnk about this the more I'm thinking its a bit more than what has been said. First thing is where you place the switch, too high and too many channels will be used most of the time, too low and the bandwidth savings are there but there is still stress on getting the data to that point.
I think I'll work and that in an all digital delivery system it just makes sense.
Do you think it would be harder or easier for cable systems to change their delivery medium? | |
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inteller
Sociopaths always win.
join:2003-12-08
Tulsa, OK
1 edit | simple solution to high def problem get rid of crappy standard def channels. no one needs HSN, HD or otherwise. I would rather watch grass grow on Sunrise Earth than watch crappy shopping channels.
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"WHEN THE LAUGH TRACK STARTS THEN THE FUN STARTS!" | |
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footballdude
Premium
join:2002-08-13
Imperial, MO
| Re: simple solution to high def problem said by inteller :no one needs HSN, HD or otherwise. I would rather watch grass grow on Sunrise Earth than watch crappy shopping channels. I agree, but someone's buying up that crap. Otherwise they wouldn't be there.
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What's certain about Darwinism is that it would take less time for (1) a single-celled organism to evolve into a human being through mutation and natural selection than for (2) Darwinists to admit they have no proof of (1) - Ann Coulter | |
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N3OGH
Bear patrol must be working like a charm
Premium
join:2003-11-11
Philly burbs
·Verizon FIOS
·Verizon Online DSL
| Re: simple solution to high def problem Yeah, shiftless houseFraus and empty nesters that have nothing better to do then spend cash on useless trinkets rather than save for retirement...
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Never ask what sort of a computer a guy drives. If he's a Mac user, he'll tell you. If not, why embarrass him? -Tom Clancy | |
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alfnoid
Premium,MVM
join:2002-02-18
| I'm dreading it... Only because I don't watch all that much tv and I only have analog service. I don't want a box for each tv in my house.
It isn't the end of the world, but I don't want to have to provide a credit card to them to get a box (no they don't do this everywhere, but in some places they do) nor do I want to deal with the box let alone pay for multiple ones just to get service period. Especially on my HTPC which does just fine with the analog I have now.
I'm sure that it will happen sooner or later, but here is my vote for later. | |
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Cjaiceman
Premium,MVM
join:2004-10-12
Parker, CO
 ·Comcast Workplace
·Comcast
| Re: I'm dreading it... said by alfnoid :Only because I don't watch all that much tv and I only have analog service. I don't want a box for each tv in my house. ...nor do I want to deal with the box let alone pay for multiple ones just to get service period. I would not mind having a box for each TV, but I do not want them to charge you for it. I have the digital package w/ HD for my main tv, but just regular analog on the other two TV's. I would not mind moving them to SDV, but there should be no additional cost. I think thats the only way they will get it to fly with the main customers, otherwise they will start doing the model of Satellite, and I don't like paying per TV for standard channels.
Another thought I just had is it will help prevent people from stealing cable as they will no longer be able to get standard TV w/o a box registered on Comcast's system. That should also help lower prices (or at least keep them from going up more).
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Hot Jamz 94FM »cjaiceman.is-a-geek.com/hotjamz/hotjamz.pls | |
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MadMANN
Premium
join:2005-08-19
·Comcast
| Re: I'm dreading it... I predict that sooner or later, the whole "box rental" fee will no longer be broken down. More than likely, they will include it in the price of packages. IE, you want the "Gold" package on four sets: $xx.cc.
Plus, they get cheaper for the providers and smaller in size every time a new series comes out. The Motorola DCT-700 is the size of a cable modem.
Also, don't forget the 2way cable card in the future (if they can make the TV manufacturers follow a standard). | |
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HorseTooth
@mellon.com
| That's why Dish network is great.... their boxes control 2 TVs... half the boxes... and thus half the $$ you're spending on the boxes. You get all the channels you're paying for on all your TVs too.
Plus, if it's a DVR you can watch the recorded content on either TV. Bea-u-ti-ful.
Cable companies could do this... but it's not in their interest to find ways to save their customers money or give them better features unless they are forced to by the competition. | |
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Mr Anon
@il.us
| I was dreadning that too but someone brought up a good idea and it could be a possible product by now. Basically there would be a box like the netpop the phone company has on your house (even if its a condo or appartment, there is one somewhere!) Bascially there they'd put a unit that would durn the all digital broadcast back to analog and serve it up to you. How expensive would that be I dunno and it would still not provide the extra service just basic expeanded and maybe a few others but no rental or on demand. Also my other nitpick with digital is that I can tell a digital channel from analog and neither look at good as broadcast with a good antenna. Can't win them all I guess. | |
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ColorBASIC
8-bit Fun
Premium
join:2006-12-29
Corona, CA
| They don't have to compete with DTV's "100" HD channels Each local Comcast cable system only has to carry the few national HD channels along with locals while DirecTV is trying to broadcast every single HD local.
DirecTV's 100 channel claim is a bit misleading as individual subscribers won't be seeing it. They'll get a few HD locals along with a few HD premiums like perhaps Universal HD, FoodTV HD, Nat Geo HD, and so on. | |
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| Enlightener
join:2006-01-28
Cedar Park, TX
·AT&T U-Verse
1 edit | Re: They don't have to compete with DTV's "100" HD channels While I don't believe D* will have it done by the end of this year, the writing really is on the wall for each market to get close to 100 HD channels. They have spent the last year getting 3-4 HD locals in dozens of markets over the last year and the next step will be to start lighting up as much HD national as content providers will soon be stepping up to the plate.
See:
»www.tvpredictions.com/askswanni012507.htm | |
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| GhostDoggy
join:2005-05-11
Duluth, GA
| Considering that DirecTV cannot even deliver high-definition content without down-rezzing and over-compressing it first, I say that the 100 HD channels claim is more like 25 channels of crap. As such, I doubt Comcast or anyone else needs to worry about what crap DirecTV id shoveling these days. | |
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cypherstream
Looking forward to the future of things.
Premium,MVM
join:2004-12-02
Reading, PA
clubs:
| It's about time It's about time Comcast looks into this technology. Time Warner has been VERY successful in recovering much needed bandwidth using SDV. Originally only Scientific Atlanta boxes and software had the capability for SDV, but Motorola is getting into the game. It's a matter of time until more providers follow. The only drawback is that channels on the switch will not be accessible from one way cable cards. The Comcast system in my area is just about full, and its 750 MHz. Going SDV would be much more cost effective than upgrading to 1 GHz.
I don't care how its delivered to me, as long as the signal gets to my house. Let them do whatever magic they need to compete with other providers (FIOS, DirecTV, Dish, U-Verse, etc.) | |
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floydb_1982
join:2004-08-25
Kent, WA |  My TV is not HD compatibale
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| RadioDoc
58ef2c0
Premium,ExMod 2000-03
join:2000-05-11 | Re: My TV is not HD compatibale Nothing. | |
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TomLe8
join:2002-02-01
Modesto, CA
| Channel tracking abilities? Doesn't seem like anyone's thinking of the 'viewer habit' tracking capability of SDV.
I'm not familiar with cable as it is now, but can cable companies see what channel you're watching and track your viewing habits? If so, then I guess SDV is no worse. But if not, then everyone should be afraid of SDV. | |
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Comcast's High-Def Push