Quote:
Originally Posted by qasdfdsaq
........Ideally, everyone would run FTTH but it is far too expensive, and not really a practical upgrade path right now over the current DOCSIS cable architecture.
Though to be fair, the cable from the cabinet isn't a big problem either as it can carry several gigabits, it's the number of homes and cabinets sharing one bigger cable to the fibre/optical node/CMTS.......
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Fibre or coax. It's all the same in capacity terms. The limiting factor is the number of downstream channels deployed (which is theoretically limited by the number of 8 MHz slots that divid into the downstream spectrum).
As you know, this capacity is squeezed by contention which is a function of two things: (1) the number of downstream channels deployed to an optical node; (2) the sharing strategy of VM in alloting downstream channels to locality cabinets.
There are barely 100 downstream channels available in the full downstream spectrum. A large chunk of this spectrum is currently used for TV which squeezes down further the broadband available sepctrum. I'm not sure what that is - maybe 300 MHz so about 40 DS channels available to a local hub (e.g. RDNG, HAYE). Igni knows this stuff better than I do but you see where I'm heading.
The only way of making serious inroads into top end speeds is to mimprove the infrastructure quality so that it can run at a higher QAM rating. IMO that is almost a survival matter for VM.