IPv6 day and tunnels

Tue Jun 5 14:55:06 UTC 2012

In message <E1829B60731D1740BB7A0626B4FAF0A65D374A86CB at XCH-NW-01V.nw.nos.boeing
.com>, "Templin, Fred L" writes:
> A quick comment on probes. Making the tunnel ingress probe
> is tempting but fraught with difficulties; believe me, I
> have tried. So, having the tunnel ingress fragment when
> necessary in conjunction with the original source probing
> is the way forward, and we should advocate both approaches.
> 
> RFC4821 specifies how the original source can probe with
> or without tunnels in the path. It does not have any RTT
> delays, because it starts small and then tries for larger
> sizes in parallel with getting the valuable data through
> without loss.

It's useful for TCP but it is not a general solution.  PTB should
not be being blocked and for some applications one should just force
minimum mtu use.

> Thanks - Fred
> fred.l.templin at boeing.com
-- 
Mark Andrews, ISC
1 Seymour St., Dundas Valley, NSW 2117, Australia
PHONE: +61 2 9871 4742                 INTERNET: marka at isc.org