daveinpoway
Premium
join:2006-07-03
Poway, CA | reply to Mele20
Re: Powerboost is the lamest gimmick ever.
Have you had the time to paraphrase the info you received from Visualware? I would be interested in seeing it. |
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Pizz
Hi
join:2000-10-27
Astoria, NY
 ·Verizon Online DSL
 ·RoadRunner Cable
| reply to MacLeech
said by MacLeech  :said by NormanS : The technical limitations of bandwidth on the cable plant "Last Mile" seem to indicate that bandwidth is shared at the CMTS; a little closer to home than with DSL. Cable companies have to split nodes to "add bandwidth". Basically, the B/W on the "Last Mile" is fixed, and the only way to "add capacity" is to reduce the number of subscribers sharing that bandwidth. Theoretically, the sharing could come down to one customer per node; Make it CMTS ports instead of nodes. CMTS upstream/downstream ports are the limiting factor as that is where the bandwidth is limited (by DOCSIS channel specs). Each CMTS port transmits or receives a single DOCSIS channel. A single physical node can actually be several virtual nodes (thank WDM for that) and each can have multiple upstream/downstream data channels. ...but current DOCSIS 1 and 2 modems can only connect to 1 downstream and 1 upstream channel at a time. In the end, last mile congestion comes down to how many customers are sharing the upstream/downstream CMTS ports, how the channels on those ports are configured, and the average/maximum bandwidth usage per customer. The 38 mpbs downstream channel bandwidth per CMTS downstream port is eaten up pretty quick when users are configured with 10 or 15 mbps and then saturate their connection for hours. I know, it's nitpicking, but I hate when people describe nodes as the bandwidth choke point in cable systems. Well according to TWCNYC - everytime congestion happens, they do a physical node split. According to an engineer, they no longer do logical splits. So i'm guessing each node that is configured here in NYC really doesnt have the QoS that your side of the country does, and i wouldnt be surprised.
I heard that Adelphia was upgrading to docsis 2.0 - and comcast took over all those markets, while TWC was left with 1.1 - which basically made them upgrade to 1.1 cause adelphia was already there. Is there any merit to that MacLeech?
Wondering also if Adelphia would've went to powerboost. |
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MacLeech
The one and only
Premium
join:2001-07-14
SoCal
| said by Pizz :I heard that Adelphia was upgrading to docsis 2.0 - and comcast took over all those markets, while TWC was left with 1.1 - which basically made them upgrade to 1.1 cause adelphia was already there. Is there any merit to that MacLeech? That has no merit. Most of Adelphia had DOCSIS 2.0 gear, maybe not active though, and TWC owns huge portions of Adelphia systems in CA, NY, and PA.
The major systems that Adelphia gave up to Comcast were in Florida.
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Don't mind me, I'm just trying to help...
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Anonymous_
Anonymous
Premium
join:2004-06-21
127.0.0.1
clubs:
·RoadRunner Cable
·Time Warner Cable
 ·Time Warner VOIP
| reply to Pizz
said by Pizz :said by MacLeech :said by NormanS : The technical limitations of bandwidth on the cable plant "Last Mile" seem to indicate that bandwidth is shared at the CMTS; a little closer to home than with DSL. Cable companies have to split nodes to "add bandwidth". Basically, the B/W on the "Last Mile" is fixed, and the only way to "add capacity" is to reduce the number of subscribers sharing that bandwidth. Theoretically, the sharing could come down to one customer per node; Make it CMTS ports instead of nodes. CMTS upstream/downstream ports are the limiting factor as that is where the bandwidth is limited (by DOCSIS channel specs). Each CMTS port transmits or receives a single DOCSIS channel. A single physical node can actually be several virtual nodes (thank WDM for that) and each can have multiple upstream/downstream data channels. ...but current DOCSIS 1 and 2 modems can only connect to 1 downstream and 1 upstream channel at a time. In the end, last mile congestion comes down to how many customers are sharing the upstream/downstream CMTS ports, how the channels on those ports are configured, and the average/maximum bandwidth usage per customer. The 38 mpbs downstream channel bandwidth per CMTS downstream port is eaten up pretty quick when users are configured with 10 or 15 mbps and then saturate their connection for hours. I know, it's nitpicking, but I hate when people describe nodes as the bandwidth choke point in cable systems. I heard that Adelphia was upgrading to docsis 2.0 - and comcast took over all those markets, while TWC was left with 1.1 - which basically made them upgrade to 1.1 cause adelphia was already there. Selected areas Have 2.0 from the start
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dbmaven
There's no shortage
Premium,Mod
join:1999-10-26
Sty in Sky
clubs: |  reply to Xizer
(topic move) TWC Customer gripe Powerboost is the lamest gimmick
Moderator Action
The post that was here (and all 5 followups to it), has been moved to a new topic .. »Ventura County - long rant/issue. |
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