Re: Digital Island sponsors DoS attempt

[Ian Cooper <ian () the-coopers org>]

At 09:45 -0500 2001-10-26, Quibell, Marc wrote:
> Curious Chris,
> What IP's are they probing? LAN IPs? Or just the DNS server as they claim?

Er, what if the DNS "server" happens to also be the host generating the query?

> And what then do these pings have to do with [quote from D.I.] "finding the
> nearest servers from our customers (Microsoft) to you"? What good does it do
> to ping to find distances,
> since the timing on the internet is not a constant, and neither are the
> pops, routes, hops...etc. This is why we use routing tables that are not
> constant...

It's one additional measure that probably wasn't available 
beforehand. One could also potentially correlate with what the 
routing tables are suggesting to see if there's a "better" way to get 
content out of a different surrogate to the requesting host(s).

Routing tables define reachability but aren't so hot at determining 
the actual performance of an end-to-end connection.  If you're only 
interested in the packets getting there "eventually" then that's OK. 
If you need the packets to get there in the most optimal manner (and 
yes, "optimal" can mean many things) then you probably need to look 
at some other way to do things.

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