google path mtu?

Matthew Luckie mjl at
Tue Jan 20 17:21:29 CET 2015

> It struck me that this should be possible to test on an
> host. Basically if the host can just respond to a packet with PTB,
> then checking if the size of the packets received changes or not
> would be interesting. Is anyone aware of someone implementing this
> already?

Yes, the tbit tool does this.

We have implemented parts of tbit in scamper, and in particular
modified the PMTUD test algorithm, and to add IPv6 support.  The main
limitation is that it requires IPFW (i.e. freebsd, or an older version
of MacOS X)

An example test from the past:

-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 181 bytes
Desc: not available
Url : 

More information about the ipv6-ops mailing list