Re: [Add] What to do in this potential working group

[Martin J. Dürst <[e-mail]>]

Hello Stephen, others.

On 2019/08/22 05:41, Stephen Farrell wrote:

> But that wasn't quite what I intended. ISTM clear that having O(1)
> TRRs in the world would be over-concentrated. I think it's maybe
> equally clear that with a different per-LAN recursive (which is
> kinda like today) it'd be extremely hard to authenticate those
> as TRR-like entities - so perhaps O(10^7) is too many TRRs. I do
> think considering "how many TRR-like things would be good" is a
> relevant (research?) question that could affect protocol design
> and implementations and deployments.
> 
> For example, if there's an answer at all and O(100) were that
> answer, that might change how a DoT/DoH client might usefully
> spread it's queries over those vs. if the answer were O(10^4).

I know where you want to get at, but due to the properties of the Big-O 
notation, O(1), O(10^7), O(100), and O(10^4) are all the same (because 
they are all constants, and constant factors are eliminated in Big-O 
thinking). Please check your sources if you don't remember this, or 
never have had the chance to study it. I can suggest sources if necessary.

If you want to say "about 1" or "about 100", then ~1 or ~100 or so may 
be appropriate.

In order (sic!) for Big-O notation to become useful, we have to assume 
we have a number of /n/ clients. Then, sensible answers involving Big-O 
notation may be O(n^0.5) or some such. O(n^0.5) would mean that a 
reasonable number of "TRR-like things" would be on the order of the 
square root of the number of clients.

Of course I have no idea whether it would be O(n^0.5) or O(n^0.1) or 
O(log n) or any other kind of order. A first guess will put the result 
between 1 (not O(1)) and O(n), but that's obvious and not very useful. 
However, there should be people who understand the theoretical 
framework(s) that may give more precise answers. And there should be 
people who know how to design and run experiments to get some more 
precise ideas.

Regards,   Martin.