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Ehud Gavron maintains this version of traceroute. It is derived from the original traceroute program, but adds a few features such as AS (Autonomous System) number lookup, and detection of TOS (Type-of-Service) changes along the path.

TOS Change Detection

This feature can be used to check whether a network path is DSCP-transparent. Use the -t option to select the TOS byte, and watch out for TOS byte changes indicated with TOS=x! .

As shown in the following example, GEANT2 accepts TOS=32/DSCP=8/CLS=1 - this corresponds to "LBE"

: root@diotima\[nanog\]; ./traceroute -t 32 www.dfn.de.
traceroute to sirius.dfn.de (192.76.176.5), 30 hops max, 40 byte packets
 1  swiLM1-V4.switch.ch (130.59.4.1)  1 ms  1 ms  0 ms
 2  swiNM1-V610.switch.ch (130.59.15.229)  0 ms  1 ms  0 ms
 3  swiCS3-G3-3.switch.ch (130.59.15.238)  0 ms  0 ms  0 ms
 4  swiEZ2-P1.switch.ch (130.59.36.222)  0 ms  0 ms  0 ms
 5  swiLS2-10GE-1-1.switch.ch (130.59.36.205)  4 ms  4 ms  4 ms
 6  swiCE2-10GE-1-3.switch.ch (130.59.37.1)  5 ms  5 ms  5 ms
 7  switch.rt1.gen.ch.geant2.net (62.40.124.21)  5 ms  5 ms  5 ms
 8  so-7-2-0.rt1.fra.de.geant2.net (62.40.112.22)  13 ms  13 ms  13 ms
 9  dfn-gw.rt1.fra.de.geant2.net (62.40.124.34)  13 ms  13 ms  13 ms
10  cr-berlin1-po1-0.x-win.dfn.de (188.1.18.53)  25 ms  25 ms  25 ms
11  ar-berlin1-ge6-1.x-win.dfn.de (188.1.20.34)  25 ms  25 ms  25 ms
12  zpl-gw.dfn.de (192.76.176.253)  25 ms  25 ms  25 ms
13 * ^C

On the other hand, TOS=64/DSCP=16/CLS=2 is rewritten to TOS=0 at hop 7 (the rewrite only shows up at hop 8):

: root@diotima\[nanog\]; ./traceroute -t 64 www.dfn.de.
traceroute to sirius.dfn.de (192.76.176.5), 30 hops max, 40 byte packets
 1  swiLM1-V4.switch.ch (130.59.4.1)  2 ms  1 ms  0 ms
 2  swiNM1-V610.switch.ch (130.59.15.229)  0 ms  0 ms  0 ms
 3  swiCS3-G3-3.switch.ch (130.59.15.238)  0 ms  0 ms  0 ms
 4  swiEZ2-P1.switch.ch (130.59.36.222)  0 ms  0 ms  0 ms
 5  swiLS2-10GE-1-1.switch.ch (130.59.36.205)  4 ms  4 ms  4 ms
 6  swiCE2-10GE-1-3.switch.ch (130.59.37.1)  5 ms  5 ms  5 ms
 7  switch.rt1.gen.ch.geant2.net (62.40.124.21)  5 ms  5 ms  5 ms
 8  so-7-2-0.rt1.fra.de.geant2.net (62.40.112.22)  13 ms (TOS=0!)  13 ms  13 ms
 9  dfn-gw.rt1.fra.de.geant2.net (62.40.124.34)  13 ms  13 ms  13 ms
10  cr-berlin1-po1-0.x-win.dfn.de (188.1.18.53)  25 ms  25 ms  25 ms
11  ar-berlin1-ge6-1.x-win.dfn.de (188.1.20.34)  25 ms  25 ms  25 ms
12  zpl-gw.dfn.de (192.76.176.253)  25 ms  25 ms  25 ms
13 * ^C

References

– Main.SimonLeinen - 26 Feb 2006

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