Quote:
Originally Posted by Ignitionnet
Due to excess complaining and either colouring threads due to or directly turning them to the capacity problems in his own area I as a general rule don't see his posts let alone respond to them, sorry!
Significance of bonding relates to statistical contention - the more members of a certain group that need to saturate their capacity to fill a pipe the less likely it is to happen.
100 x 10Mb users on a 100Mb pipe are far less likely to have 10% of them using capacity at the same time and maxing the pipe out than 10 x 10Mb users on a 10Mb pipe.
Now the contention ratio is the same, 10:1, however you need 10 people in the group of 100 to simultaneously max their capacity versus 1 person. The first situation is unlikely, the second one inevitable.
Even without upgrades bonding improves the equation, it's harder for say 150 customer to use 36Mb of upstream capacity than it is for 75 to use 18Mb.
For more on statistical contention Google is your friend, it's a well explained phenomenon both mathematically and practically in broadband networks.
The key part about the bonding was that to preserve the 10:1 ratio between downstream and upstream VM will need to bond 2 upstream channels as their current use of 16QAM only gives 18Mb of capacity. It's not about how good or otherwise it'll be, it literally has to be done and works fine so long as the network is managed properly in terms of number of customers on each segment and appropriate traffic management.
The key components of Virgin's problems right now are the number of customers per segment (too many) and the traffic management on 100Mb specifically (none).
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Ignition I am not mentioning my area in recent posts, but will remain to criticise VM. It seems you have took offense to the criticism heading VMs way.
Now another question which I hope roughbeast will repeat again so you will answer it.
You have just said statistical contention is important, this I agree with.
With that in mind and that there will be 200mbit user's on a 400mbit pipe like there is 100mbit user's on a 200mbit pipe, why do you think that will work when you just said having 10mbit users on a 10mbit pipe is poor. Yes its not quite the same 1 user 100% of capacity but 1 user 50% of capaicty isnt a whole lot better.
Also in regards to the bonding the top tier end user's speed are been doubled so the statistical contention remains the same.
So the question is
Example
You say smaller node sizes is better.
Yet you also say more users on same contention ratio sharing bigger pipe is better which contradicts the above.
So why dont VM merge say 4 segments into one large segment with 32 channels and 8 upstreams instead?
Having 200mbit users with 32 channels even tho the contention ratio is the same would be much better, in addition segments filled with students could be mixed with OAP segments to balance things out.