On 25 aug 2008, at 12:27, Fernando Gont wrote:
http://support.microsoft.com/kb/925280
IPv4 minimum MTU is 68 bytes,
That's kind of like "a human being can live without food for four to
six weeks". It's not a recommendation.
536 is the minimum fragment re-assembly buffer size. Falling back to
536-byte packets does not guarantee that sessions will be kept up.
But:
"PMTU black hole router detection is triggered on a TCP connection
when TCP starts retransmitting full-sized segments with the DF flag
set. TCP resets the PTMU for the connection to 536 bytes. Then, TCP
retransmits its segments when the DF flag is clear."
