Assymetric routing L3/VZ (FIOS)

Fri Apr 20 19:09:41 UTC 2012

Is anyone else seeing this? DC - DFW back to DC? AFAIK, Verizon-GNI is a 
customer of L3, so no weird peering issues should be afoot. This adds 
about 40ms to the R/T time.  The path leaving Verizon-GNI (FIOS) goes 
(seemingly) DC-DC and has lower times (<5ms) unidirectionally.

Tracing the route to pool-173-79-242-218.washdc.fios.verizon.net 
(173.79.242.218                                  )

[...]

   3 ge-6-16.car1.Baltimore1.Level3.net (4.59.244.85) [AS 65518] 4 msec 
0 msec 4                                   msec
   4 ae-11-11.car2.Baltimore1.Level3.net (4.69.134.110) [AS 65518] 0 
msec 4 msec                                   0 msec
   5 ae-8-8.ebr2.Washington1.Level3.net (4.69.134.105) [AS 65518] 4 msec 
4 msec 4                                   msec
   6 ae-72-72.csw2.Washington1.Level3.net (4.69.134.150) [AS 65518] 4 msec
     ae-82-82.csw3.Washington1.Level3.net (4.69.134.154) [AS 65518] 8 
msec 8 msec
   7 ae-61-61.ebr1.Washington1.Level3.net (4.69.134.129) [AS 65518] 4 msec
     ae-91-91.ebr1.Washington1.Level3.net (4.69.134.141) [AS 65518] 4 msec
     ae-71-71.ebr1.Washington1.Level3.net (4.69.134.133) [AS 65518] 4 msec
   8 ae-2-2.ebr3.Atlanta2.Level3.net (4.69.132.85) [AS 65518] 16 msec 16 
msec 16                                   msec
   9 ae-7-7.ebr3.Dallas1.Level3.net (4.69.134.21) [AS 65518] 36 msec 36 
msec 36 m                                  sec
  10 ae-73-73.csw2.Dallas1.Level3.net (4.69.151.145) [AS 65518] 40 msec
     ae-63-63.csw1.Dallas1.Level3.net (4.69.151.133) [AS 65518] 40 msec 
40 msec
  11 ae-4-90.edge2.Dallas3.Level3.net (4.69.145.204) [AS 65518] 44 msec
     ae-3-80.edge2.Dallas3.Level3.net (4.69.145.140) [AS 65518] 36 msec
     ae-1-60.edge2.Dallas3.Level3.net (4.69.145.12) [AS 65518] 36 msec
  12 MCI-level3-ae.dallas3.level3.net (4.68.62.34) [AS 65518] 36 msec
     mci-level3-30g.dallas3.level3.net (4.68.62.166) [AS 65518] 36 msec
     MCI-level3-ae.dallas3.level3.net (4.68.62.34) [AS 65518] 36 msec
  13 0.ge-0-0-0.DFW01-BB-RTR1.verizon-gni.net (152.63.2.146) [AS 65518] 
36 msec 3                                  6 msec
     0.ae2.DFW01-BB-RTR2.verizon-gni.net (152.63.2.229) [AS 65518] 36 msec
  14  *  *  *

We're opening a ticket with them, but figured NANOG is an often better 
place for these resolutions.

Thanks in advance,

Deepak Jain
AiNET
Home of CyberNAP
www.ai.net