On 01/04/2012 11:55 PM, Brian E Carpenter wrote: > That's why RFC 4821 describes MTU probing hidden in the transport > layer, where hopefully firewalls would let it be. You will > probably look in vain for widely deployed versions of RFC 4821.
The problem with RFC4821 (assumming the ICMP-free variant) is that it has a longer convergnece time that ICMP-enabled PMTU. That's why people think of RFC4821 as a mechanism for PMTUD blackhole detection rathern than as a repalcement for traditional PMTUD (i.e., you use the transport-layer probes when it looks like tradictional PMTUD is not working (possibly as a result of filtered ICMP error messages)). Thanks, -- Fernando Gont SI6 Networks e-mail: [email protected] PGP Fingerprint: 6666 31C6 D484 63B2 8FB1 E3C4 AE25 0D55 1D4E 7492 -------------------------------------------------------------------- IETF IPv6 working group mailing list [email protected] Administrative Requests: https://www.ietf.org/mailman/listinfo/ipv6 --------------------------------------------------------------------
