On 02/12/2013 04:02 PM, Alexander Arseniev wrote:
and DNS over UDP would not be experiencing issues due to too small MTU because own DNS payload limit is smaller than smallest real MTUs out there
Not so. The EDNS buffer size option allows clients to request UDP DNS replies anything up to 4096 bytes, which are typically sent as IP fragmented UDP packets.
Such DNS request/replies are now quite common, particularly between a recursive resolver and authoritative service. DNS RR types such as DNSKEY, RRSIG/NSEC and TXT/SPF are all capable of padding DNS payloads to sizes where this is necessary.
So, DNS is a quite-valid example for MTU-sized frames. _______________________________________________ cisco-nsp mailing list [email protected] https://puck.nether.net/mailman/listinfo/cisco-nsp archive at http://puck.nether.net/pipermail/cisco-nsp/
