Contention/Oversubscription maths

Adam Armstrong lists at
Fri May 27 15:58:50 UTC 2011

On 27/05/2011 15:23, Jay Ashworth wrote:
> ----- Original Message -----
>> From: "Adam Armstrong"<lists at>
> Residence customers will tolerate a lot more oversubscription than business,
> enterprise, and server going on down the list of oversubscription, but
> happily *up* the list of "how much can I charge".  Remember that QoS and
> load shaping don't work all that will across the internet at large,
> but they work pretty decently inside a single switch; you can prioritize
> customers who are willing to pay extra for it.  The problem is similar
> to airline bookings; it is possible, in the immortal words of Dave Barry,
> to envision a situation -- this will happen in your lifetime -- where
> no two customers pay exactly the same price.  :-)
We're hoping we don't have to do any QoS or shaping, as we don't want 
any links to be saturated. From the data i've gotten it seems that is 
possible with many hundreds of 100Mbit customers on a 1000Mbit backhaul.

The 1G product is the exception to that, and it's a little unclear where 
that sits, probably in a box labelled "here be failure".


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