Re: Bottlenecks and link upgrades

["Radu-Adrian Feurdean" <nanog () radu-adrian feurdean net>]

On Wed, Aug 12, 2020, at 09:31, Hank Nussbacher wrote:
> At what point do commercial ISPs upgrade links in their backbone as 
> well as peering and transit links that are congested?  At 80% capacity? 
>  90%?  95%?  

Some reflections about link capacity:
At 90% and over, you should panic.
Between 80% and 90% you should be (very) scared.
Between 70% and 80% you should be worried.
Between 60% and 70% you should  seriously consider speeding up the upgrades that you effectively started at 50%, and 
started planning since 40%.

Of course, that differs from one ISP to another. Some only upgrade after several months with at least 4 hours a day, 
every day (or almost) at over 95%. Others deploy 10x expected capacity, and upgrade well before 40%.