Re: [re-ECN] ECN fundamentals pt2/2 (was: Re: Name for BoF?)

[Michael Menth <[e-mail]>]

Hi Bob,

Bob Briscoe schrieb:
> An example may help. Two options my own company offers to residential 
> customers for the same access rate today are:
> volume allowance         charge
> 10GB/month               GBP15/month
> 20GB/month               GBP20/month
> This is like saying basic access with zero usage is GBP10 then add 
> GBP5/10GB/month for usage. Even if this ISP only offered one tariff 
> (say GBP18/month) it still notionally includes GBP8 to put towards 
> capacity expansion - it's just a single average price where light 
> users contribute more to new capacity than is "proper" and heavy users 
> less.
>
> I would propose that a congestion allowance would replace this volume 
> allowance, so it might look like this:
> congestion-volume
> allowance                charge
> 10MB/month               GBP15/month
> 20MB/month               GBP20/month
> This assumes congestion is expected to be about 0.1% on average so 
> 1/1000 of average volume is congestion-volume. But with a 
> congestion-volume allowance you could transfer a lot more volume if 
> you did it at night or even at peak time if you used a protocol like 
> LEDBAT.
>

Is a congestion allowance in MB/month which is controlled by a simple 
counter at the access really helpful? This allows users to cause lots of 
congestion at the beginning of the month. I thought that a maximum 
congestion rate in KB/s which is controlled by a kind of token bucket is 
needed to do congestion policing and that this is one of the core 
concepts of re-refeedback to achieve fair bandwidth sharing among users? 
This corresponds rather to a maximum access speed  than to a maximum 
amount of volume allowance. A monthly volume allowance can be combined 
with both a maximum access speed and a maximum congestion rate.

True or not? Where's the fault?

Apart from that, I wonder whether a monthly congestion allowance or a 
maximum congestion rate can be sold to the customer because that is more 
abstract and harder to verify for the user. Even I do not know what I 
get for a congestion allowance of 1 MB/month or a maximum congestion 
rate of 10 KB/s. That was one of the criticisms I've heard when 
discussing about re-feedback. Opinions?

Regards,

    Michael

-- 
Dr. Michael Menth, Assistant Professor
University of Wuerzburg, Institute of Computer Science
Am Hubland, D-97074 Wuerzburg, Germany, room B206
phone: [phone] (new), fax: [phone]
mailto:[e-mail]
http://www3.informatik.uni-wuerzburg.de/research/ngn