Re: What DNS Is Not

[bmanning () vacation karoshi com]

On Sun, Nov 08, 2009 at 07:42:18PM -0500, David Andersen wrote:
> On Nov 8, 2009, at 7:30 PM, bmanning () vacation karoshi com wrote:
>
> > On Sun, Nov 08, 2009 at 07:17:16PM -0500, David Andersen wrote:
> > > "Our trace-driven simulations yield two findings. First, reducing the
> >
> >                 -----------
> > > -Dave
> >
> >     a simulation is driven from a mathmatical model, not real world
> >     constructions.
>
> Hi, Bill -
>
> The paper is worth reading.
>
> "The paper also presents the results of trace-driven simulations that  
> explore the effect of varying TTLs and varying degrees of cache  
> sharing on DNS cache hit rates. "
>
> emphasis on *trace-driven*.  Now, you can argue whether or not their  
> traces are representative (whatever that means) -- they used client  
> DNS and TCP connection traces from MIT and KAIST, so it definitely has  
> a .edu bias, iff there is a bias in DNS traffic for universities vs.  
> "the real world", but to the extent that their traces represent what  
> other groups of users might see, their evaluation seems accurate.
>
>   -Dave

        I'm not debating the traces - I wonder about the simulation
        model.  (and yes, I've read the paper)

--bill