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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#44546A'>Yeah, and what do you do with a traceroute that looks like this…. (ip address intentionally changed)<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#44546A'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#44546A'>C:\>tracert -d -w 1 1.2.3.4<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#44546A'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#44546A'>Tracing route to 1.2.3.4 over a maximum of 30 hops<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#44546A'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#44546A'> 1 8 ms 5 ms 5 ms 96.8.191.129<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#44546A'> 2 * * * Request timed out.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#44546A'> 3 * * * Request timed out.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#44546A'> 4 * * * Request timed out.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#44546A'> 5 * * * Request timed out.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#44546A'> 6 * * * Request timed out.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#44546A'> 7 * * * Request timed out.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#44546A'> 8 * * * Request timed out.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#44546A'> 9 * * * Request timed out.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#44546A'> 10 * * * Request timed out.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#44546A'> 11 * * * Request timed out.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#44546A'> 12 * * * Request timed out.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#44546A'> 13 * * * Request timed out.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#44546A'> 14 * * * Request timed out.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#44546A'> 15 * * * Request timed out.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#44546A'> 16 * * * Request timed out.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#44546A'> 17 267 ms 202 ms * 1.2.3.4<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#44546A'> 18 205 ms 175 ms * 1.2.3.4<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#44546A'> 19 160 ms 233 ms * 1.2.3.4<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#44546A'> 20 199 ms 201 ms * 1.2.3.4<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#44546A'> 21 213 ms 206 ms * 1.2.3.4<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#44546A'> 22 165 ms 158 ms * 1.2.3.4<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#44546A'> 23 237 ms 158 ms * 1.2.3.4<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#44546A'> 24 158 ms 290 ms * 1.2.3.4<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#44546A'> 25 158 ms 160 ms 158 ms 1.2.3.4<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#44546A'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#44546A'>Trace complete.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#44546A'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#44546A'>C:\><o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#44546A'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#44546A'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#44546A'><o:p> </o:p></span></p><p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> NANOG [mailto:nanog-bounces@nanog.org] <b>On Behalf Of </b>Etienne-Victor Depasquale<br><b>Sent:</b> Thursday, December 12, 2019 1:18 AM<br><b>To:</b> Valdis Klētnieks<br><b>Cc:</b> nanog@nanog.org<br><b>Subject:</b> Re: Short-circuited traceroutes on FIOS<o:p></o:p></span></p><p class=MsoNormal><o:p> </o:p></p><div><p class=MsoNormal>Traceroute is becoming more and more an expert's tool because interpretation of its results isn't straightforward.<o:p></o:p></p><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>I had written a paper last year and mentioned its misuse in academia in the context of estimating the number of energy-consuming devices between a source and a destination. <o:p></o:p></p></div><div><p class=MsoNormal>Traceroute was being used to count the number of physical router devices from the hop count, notwithstanding the use of MPLS in domain cores.<o:p></o:p></p></div><div><p class=MsoNormal>To an external observer, this results in significant underestimation of the energy consumption in the path from source to destination.<o:p></o:p></p></div></div><p class=MsoNormal><o:p> </o:p></p><div><div><p class=MsoNormal>On Thu, Dec 12, 2019 at 12:51 AM Valdis Klētnieks <<a href="mailto:valdis.kletnieks@vt.edu">valdis.kletnieks@vt.edu</a>> wrote:<o:p></o:p></p></div><blockquote style='border:none;border-left:solid #CCCCCC 1.0pt;padding:0in 0in 0in 6.0pt;margin-left:4.8pt;margin-right:0in'><p class=MsoNormal>On Wed, 11 Dec 2019 19:26:09 +0200, Saku Ytti said:<br>> On Wed, 11 Dec 2019 at 19:14, Rob Foehl <<a href="mailto:rwf@loonybin.net" target="_blank">rwf@loonybin.net</a>> wrote:<br>><br>> > Support claims that it was a mistake, but it's also been 15+ months and<br>> > it's pretty deliberate behavior. Draw your own conclusions...<br>><br>> TTL decrement issues are fairly common across multiple vendors and hw,<br>> can be sw can be hw limit<br><br>Yes, but you need to screw up gloriously on the decrement if you think that<br>"I decremented and it's zero now" means "therefor it must have been addressed<br>to me, so I'll send an ECHO REPLY instead of TTL EXCEEDED".<o:p></o:p></p></blockquote></div><p class=MsoNormal><br clear=all><o:p></o:p></p><div><p class=MsoNormal><o:p> </o:p></p></div><p class=MsoNormal>-- <o:p></o:p></p><div><div><p class=MsoNormal><span style='font-family:"Tahoma","sans-serif";color:#888888'>Ing. Etienne-Victor Depasquale<br>Assistant Lecturer<br>Department of Communications & Computer Engineering<br>Faculty of Information & Communication Technology<br>University of Malta</span><o:p></o:p></p><div><p class=MsoNormal>Web. <a href="https://www.um.edu.mt/profile/etiennedepasquale" target="_blank">https://www.um.edu.mt/profile/etiennedepasquale</a><o:p></o:p></p></div></div></div></div></body></html>