Re: rfc1916 or rfc2916bis and DNS packet sizes

["Conroy, Lawrence (SMTP)" <]

On 31 Mar 2004, at 11:01 am, Jim Reid wrote:

> > > > > > "lwc" == Conroy, Lawrence (SMTP) lwc@localhost writes:
>     lwc> Thus it's only "easy" for those folks having a single contact
>     lwc> - remember that some of the old clients only use UDP queries
>     lwc> (without EDNS0 support).
>
> A host that cannot do DNS lookups over TCP is broken and needs to be
> fixed. If the query response is bigger than the standard maximum
> payload of 512 bytes, the server sends a truncated response. The
> client is then supposed to repeat the query over TCP to get all the
> data. In this context EDNS0 is just a way of negotiating a bigger UDP
> payload. EDNS0 can't guarantee that truncated responses won't ever
> happen, though it should make them less likely. Therefore support for
> queries over TCP is still needed.
>
> Truncated responses wouldn't be too hard to achieve in ENUM even with
> an 8K EDNS0 UDP packet. Mix a delegation holding a handful of NAPTRs
> with DNSSEC and you're just about there.
Hi Folks,
  one word (well, acronym): GPRS
  another one: JAVA
In an ideal world, all things are possible. In a cheap handy, however...

(in an ideal world, DNSSEC would be feasible :).

atb,  L