Routing through non-addressable space???

Sat Jan 26 09:04:39 UTC 2002

At 09:35 PM 1/25/02 -0600, you wrote:

Mmmmmm... this trace is from an @Work/Excite circuit that is about to go 
dark. The "cable modem" is (as far as I can tell) the Cisco 2600 at the 
customer site. Either that or @Work's customer gateway address.

>Cable modems actually "have" two IP's: one rfc1918 that they use for
>provisioning purposes and in the actual IP of the cable modem device,
>one real IP that they pass on to the end-user's device.  Many of the
>newer cable modems are now showing the private IP in traces where
>previously they'd pass and not respond to ICMP.  As for why, who knows?
>My best guess is to ease tracking down offending IP's vs. users.
>
>Michael Graham
>
>-----Original Message-----
>From: owner-nanog at merit.edu [mailto:owner-nanog at merit.edu] On Behalf Of
>Turpin, Mark
>Sent: Friday, January 25, 2002 8:43 PM
>To: 'Simon Higgs'; 'nanog at merit.edu'
>Subject: RE: Routing through non-addressable space???
>
>
>Routing through a cable interface that has a 10.x address as its primary
>ip
>address would be my first guess, esp. due to the 24.x address.
>
>!
>int cable3/0
>ip address 10.x.x.x. x.x.x.x.x
>ip address public.for.cpe.equip mask.mask.mask.mask secondary
>
>cheers,
>
>Mark Turpin
>Charter NOC
>mturpin at chartercom.com
>
>-----Original Message-----
>From: Simon Higgs [mailto:simon at higgs.com]
>Sent: Friday, January 25, 2002 8:47 PM
>To: nanog at merit.edu
>Subject: Routing through non-addressable space???
>
>
>Can someone explain this trace to me. How on earth did the 10.0.0.0
>network
>get inserted into the last hop?
>
>#    IP address       Host name                                Round
>trip
>time
>
>4    24.130.2.243     GSR1-SRP4-0.lsanhe4.we.mediaone.net 64 ms
>5    24.130.2.242     GSR2-SRP4-0.lsanhe3.we.mediaone.net 71 ms
>6    12.125.98.13     Unavailable                         79 ms
>7    12.123.28.94     gbr2-p100.la2ca.ip.att.net          94 ms
>8                     No response
>9    12.122.11.226    ggr1-p340.la2ca.ip.att.net          110 ms
>10   192.205.32.246   att-gw.la.home.net                  112 ms
>11   24.7.74.182      wbb1-pos2-0.pop1.ca.home.net        120 ms
>12   10.252.25.118    Unavailable                         134 ms
>13   209.125.128.80   Unavailable                         141 ms

Best Regards,

Simon

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