Current trends in capacity planning and oversubscription

Sean Donelan sean at donelan.com
Fri Nov 12 23:52:20 UTC 2010


On Wed, 10 Nov 2010, Curtis, Bruce wrote:
>  If we take our current ISP bandwidth and increase it by 50% every 
>year for 5 years it would be about twice the 100 Mbps per 1,000 
>students/staff recommendation.

Is 50% growth each year typical these days?  In the dot-com boom days, 
people said 100% growth, other people have suggested 20% may be more 
reasonable now.  A problem with government network capacity 
planning/growth forecasts is you will be stuck with whatever you choose, 
too high or too low, for many years because the budget cycle is so long.

It would be great if there was some actual data available.  But it seems
more typical to benchmark/compare to do network capacity planning with 
other government agencies, so we end up with X-Mbps per Y,000 people.
Yes, I know it depends.  1,000 people downloading data from LHC 
experiments will be different from an administrative school office. 
The difference is the people using LHC data usually have someone who can 
figure out network capacity planning, while the people in an 
administrative school office may not have anyone.

So what is a reasonable network capacity for 1,000 students now and in 5 
years.




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