User: SngBrdB

Re:If comcast want'sto do this

On: Comcast Defends Role As Internet Traffic Cop

I disagree with the analogy, and here's why. Comcast limits me to dl/ul speeds of 6Mbps down and 768Kbps up. In other words, Comcast has already put into place measures to prevent me from hogging the network, and these measures are built into the pricing scheme. Furthermore, Comcast has the ability to prioritize traffic to ensure each channel (user) is getting their fair share and not forced to wait for a "hog". In fact, if Comcast gave top priority to traffic on ports 80, 25, 110, and 443, there would be no need to limit p2p at all (imo). A more correct analogy would be an all-you-can-eat buffet where each diner gets one plate, and can't go back for a second plate until all other diners have gotten their equally-sized plates. Now before anyone jumps all over me about time-sharing, and how not everybody is expected to use their full allocation at once, I'd like to share some more information with you. Coax is typically quoted as having 30Mbps throughput. This is not correct. 30Mbps is a throughput per channel. From http://www.cable-modem.net/tt/primer.html:

A cable television system typically has 60 or more channels, and most of them are used for programming services like CNN, ESPN and HBO. These channels also can be used to offer high-speed Internet access. Each channel offers 27 mbps of downstream capacity and 10 mbps of upstream capacity, which is shared by a small cluster of homes. Because data traffic is bursty, several hundred cable modem users can surf at the same time without any loss of performance. If speeds begin to fall off due to heavy traffic, the cable operator can allocate more channel space to preserve high performance levels.

So guess what? At 6:00, when everyone turns their TV on to the nightly news at the same time? Same problem!! But you don't see your television signal heaving all over tuner... because Comcast knows they can't put more subscribers on a hub than will be simultaneously watching TV. ...See where I'm going with this? It's also very interesting that channel space is dynamic. If internet traffic is just another channel, can't it also be dynamic? A final bit of info, to give you perspective how much bandwidth coax really has: the Multimedia over Coax Alliance (members include Comcast, Cox, Verizon, and many others) looks to the capacities of existing and future technologies. They've done studies on HDTV and internet over coax, and results of these studies where presented at WinHEC 2007. http://mocalliance.org/en/index.asp From the site:

The Multimedia over Coax Alliance (known as MoCA(TM)) is an open, industry driven initiative promoting distribution of digital video and entertainment through existing coaxial cable in the home. MoCA's primary requirements are: * No new wires * No installation or truck roll * No interference with existing networks * If you have coax, it works. * Compliments [sic] any wireless network

At WinHEC 2007, MoCA presented the results of a field test performed using 250 homes. The PowerPoint presentation is available from Microsoft's download site: http://download.microsoft.com/download/a/f/d/afdfd50d-6eb9-425e-84e1-b4085a80e34e/CON-T477_WH07.pptx The goals of the field test were to use existing coax to provide simultaneous internet and stutter-free HDTV to multiple rooms of a house without impacting the other users on the network. This functionality has since been deployed to more than 200,000 homes. The results: * Speeds of >110Mbps net throughput in 97% of all outlets WITH NO CHANGES TO EXISTING SYSTEM! * Packet Error Rate less than 10-6 * Latency less than 5ms With "simple remediation", the results were 100% of homes achieved >95Mbps on *every* path in the home. Download the ppt, it's an