Traceroute implements -t switch which can be used to set type-of-service byte in the datagrams. Certain routers are configured to change the value of TOS (mainly to implement differentiated services model). It's useful to know if this is happening. I've taken a patch in a different traceroute program, enhanced it a bit plus documented it and submitted it to the authors (last release of traceroute was year or two ago though, so I'm not looking forward to response..). The change is minimal and affects only operation in -t mode (see the patch).
Created attachment 71405 [details] monitor TOS byte changes with -t
Added patch in latest rawhide version. Thanks, Read ya, Phil