Comments on: AT&T Internet Outage in Bay Area Disrupts Internet Traffic http://www.theinternetpatrol.com/att-internet-outage-in-bay-area-disrupts-internet-traffic/ Internet Safety, Windows Updates, Internet News, and More Sat, 21 Nov 2009 20:42:56 +0000 http://wordpress.org/?v=2.6.3 By: Bill Cole http://www.theinternetpatrol.com/att-internet-outage-in-bay-area-disrupts-internet-traffic/#comment-41254 Bill Cole Wed, 07 Feb 2007 16:43:19 +0000 http://www.theinternetpatrol.com/?p=1492#comment-41254 Just a side-note on the '*' in traceroute output. It doesn't necessarily mean that there is nothing there, it can mean that a router (or a string of them) in the path are either configured intentionally to not respond to traceroute's probe packets or are responding in a fashion that some other machine in the return path is seeing as bogus. An example of the latter would be the use of private addresses in routers in a way that causes their ICMP responses to be sent with source addresses in a RFC1918 network that some other routers and firewalls reasonably consider bogus and drop-worthy. In the end, it is not definitive that packets are traveling off into nowhere just because traceroute trails off into asterisks. Just a side-note on the ‘*’ in traceroute output. It doesn’t necessarily mean that there is nothing there, it can mean that a router (or a string of them) in the path are either configured intentionally to not respond to traceroute’s probe packets or are responding in a fashion that some other machine in the return path is seeing as bogus. An example of the latter would be the use of private addresses in routers in a way that causes their ICMP responses to be sent with source addresses in a RFC1918 network that some other routers and firewalls reasonably consider bogus and drop-worthy.

In the end, it is not definitive that packets are traveling off into nowhere just because traceroute trails off into asterisks.

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