Quote:
Originally Posted by Horizon
Ok, a few questions:
Would it be accurate to say that 16 channels or 800mb is the maximum download capacity available in any one area? And potentially using the most extreme example, that 800mb has to serve the following:
6 large street cabinets of 96 customers each = 576 customers in one launch cabinet.
5 launch cabinets of 576 customers each = 2880 customers at one node.
Thus one node at its maximum capacity has to share 800mb between 2880 customers. Is that correct so far?
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These extrapolations have been attempted many times. In densely populated areas, cabs are usually fully subscribed and many a horror story exists about splitters in the cab.
So your 2880 customers per optical node is a maximum where no splitters are used. The node serves a service group of 16 downstream channels and the CMTS aims to load balance customers onto 8 channel bonding groups by some algorithm or other that can be tweaked by the admin.
In my area, I have examined street cabs and have assessed that an optical node probably services not more than 500 customers. I did a sensibility check on that. The Liberty Global web site says that VM passes 12 million homes and has 4 million cable broadband customers. That's 33%. In my area there are c. 3,000 homes passed. We have 2 optical nodes in Winnersh - so that's c. 500 customers per optical node.
Does that help?
So, make of that what you will.