Reviews:
 ·ProLog
 ·DIRECTV
| Possible, hopefully we can cut through all that noise Sure this is possible. At least with the Cisco uBR10012 S-CDMA with logical channel support was available since software release 12.2(33)SCC. Anyone familiar with Cisco can check out the documentation here:
»www.cisco.com/en/US/docs/ios/cab···p1047623
Those sub 20 MHz area's are really noisy. Also what about Scientific Atlanta based systems. A lot of those I see the SA DAVIC return up as high as 20 MHz. That put's a little roadblock in how many channels you want to squeeze in from 22 ~ 40 MHz. The Moto systems can be configured to shoot upstream as low as 8 MHz, leaving about 11-42 as your CMTS playground in a perfect noise free world. I'm not as knowledgeable in the SA set top area to know how low they can configure their return.
Squeezing in 4 x 6.4 MHz 64QAM channels in the upstream is quite a challenge. Also you alienate all the DOCSIS 1/1.1 modems. I know as of Dec 2009 Comcast stopped supporting DOCSIS 1.0 modems, which is great.
Now 1.1 modems can work with S-CDMA, but I don't think they can do it at 64QAM. Here's a great pdf presentation from Ron Hranac of Cisco regarding deploying 64QAM in the upstream:
»chapters.scte.org/rockymtn/docum···blic.pdf
This guy is like a God to cable RF. He is a genius, and anyone half interested in the technical sides of things should really read this guy's work. |
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 kpfx
join:2005-10-28
San Antonio, TX
·RoadRunner Cable
| I do remember both Motorola and Scientific Atlanta (er... I mean Cisco now) were working on moving their cable box returns to the CMTS, so that should also free up some more upstream spectrum for DOCSIS bonding.
Motorola's DVRs and HD receivers have been shipping with a DOCSIS modem built-in since day 1. I believe its similar with SA too... |
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Reviews:
·ProLog
·DIRECTV
1 edit | said by kpfx:I do remember both Motorola and Scientific Atlanta (er... I mean Cisco now) were working on moving their cable box returns to the CMTS, so that should also free up some more upstream spectrum for DOCSIS bonding. Motorola's DVRs and HD receivers have been shipping with a DOCSIS modem built-in since day 1. I believe its similar with SA too... Yeah the latest ones, but what about the legacy set tops? Just force people to swap them out? Motorola ones are fine, they all work down really low. I'm going to do a little more research for the SA/Cisco set tops, particularly the Explorer 2200 and 3200 which are popular no frills models.
SA2200 - Only DAVIC transmitter (not DOCSIS)
»www.cisco.com/en/US/prod/collate···5b36.pdf
SA3200 - Only DAVIC
»www.cisco.com/en/US/prod/collate···5b93.pdf
SA4200 (and later) DOCSIS support
»www.cisco.com/en/US/prod/collate···5c44.pdf
As of SA System 4 release, DOCSIS only return is supported:
»www.cisco.com/en/US/prod/collate···8888.pdf |
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MRCUR
join:2007-03-09
Columbia, PA | reply to cypherstream
Why aren't you working for Comcast Cypher? You know your s@1t. |
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netcoolPremium
join:2008-11-05
Englewood, CO
kudos:9 | reply to cypherstream
said by cypherstream:Sure this is possible. At least with the Cisco uBR10012 S-CDMA with logical channel support was available since software release 12.2(33)SCC. It's going to require a lot of linecard swaps first, most of the 10ks have MC5X20Us and not the H cards. |
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