[106466] in North American Network Operators' Group
Re: Great Suggestion for the DNS problem...?
daemon@ATHENA.MIT.EDU (Mohacsi Janos)
Tue Jul 29 10:32:40 2008
Date: Tue, 29 Jul 2008 16:32:18 +0200 (CEST)
From: Mohacsi Janos <mohacsi@niif.hu>
To: "Steven M. Bellovin" <smb@cs.columbia.edu>
In-Reply-To: <20080729102302.3d0956f4@cs.columbia.edu>
Cc: nanog@nanog.org
Errors-To: nanog-bounces@nanog.org
On Tue, 29 Jul 2008, Steven M. Bellovin wrote:
> On Tue, 29 Jul 2008 15:56:19 +0200
> Colin Alston <karnaugh@karnaugh.za.net> wrote:
>
>>> DNS uses UDP.
>>
>> Ahh yes of course..
>>
>> Why does it use UDP? :P
>>
> In this situation, UDP uses one query packet and one reply. TCP uses 3
> to set up the connection, a query, a reply, and three to tear down the
> connection. *Plus* the name server will have to keep state for
> every client, plus TIMEWAIT state, etc. (Exercise left to TCP geek
> readers: how few packets can you do this in? For example -- send the
> query with the SYN+ACK, send client FIN with the query, send server FIN
> with the answer? Bonus points for not leaving the server's side in
> TIMEWAIT. Exercise for implementers: how sane can your stack be if
> you're going to support that?)
It was advocated as T/TCP in 90s.
http://www.kohala.com/start/ttcp.html
Not accepted widely:
http://en.wikipedia.org/wiki/T/TCP
Regads,
Janos Mohacsi
