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Re: censored? corrected [Steve Pizzo cited in The Spotlight]
In article <[email protected]>,
Rich Salz <[email protected]> wrote:
> >Originally DNS was just a handy user-friendly thing, but then
[...]
> Hunh?
>
> The Arpanet always used hostnames.
Sorry. But still, then intent was to be user-friendly (right?), and
a side effect was to make it possible to renumber without anyone noticing.
Renumbering didn't affect the health of the net until recently, with
CIDR, where blocks of IP addresses could be aggregated arbitrarily.
A provider might now get 10.11.12/22 (i.e., a 22-bit-long prefix), and
then assign customers 10.11.12/24, 10.11.13/23, &c., with only one entry
in the backbone routing tables. To make this work you have to renumber
when you change providers. Fortunately, we have DNS to provide a name
more stable than the IP address.
That's the connection between DNS and routing, and it's why using names
instead of numbers is Good.
--
Shields.