Address Sorting NOT in V8

[Kevin Darcy]

Jim Reid wrote:

> >>>>> "Kevin" == Kevin Darcy <kcd at daimlerchrysler.com> writes:
>
>     >>  Because relying on the order that the resource records in an
>     >> answer from a name server being in a specific order was
>     >> generally not a particularly smart thing to do. Think
>     >> round-robin DNS for instance. Or resolvers that "sort" the
>     >> addresses in an answer. Or resolvers that get one order of the
>     >> RRset when they query one name server for some name but a
>     >> different order if they query another name server for the
>     >> self-same name. Or the name server forwards a query to some
>     >> other name server that returns an answer that's optimised for
>     >> the server that forwarded the query, not the original host that
>     >> made it, etc, etc.
>
>     Kevin> Jim, it works just fine on an intranet where all of the
>     Kevin> nameservers can be configured with the same sortlists.
>
> True, but intranets are not quite the same as the Internet because
> things like the network topology and IP address allocation should be
> more structured in the former. And even on an intranet I'm not
> convinced that the name server should be sorting its answers. I think
> that should be done by the resolver where whatever sort criteria are
> considered appropriate - alphabetical, network routing, phase of the
> moon - for the application that made the lookup. Why impose a "one size
> fits all" approach from the name server? Sometimes this can be OK, but
> not in the general case IMHO.

The two are not mutually exclusive, of course. The nameserver can sort the
answers one way -- network sorting would seem to make sense for the vast
majority of applications -- and then if the resolver or application has some
special sorting needs, like phase-of-the-moon or whatever, it can re-sort
the addresses.


- Kevin