nanog mailing list archives
Re: AT&T carrying rfc1918 on the as7018 backbone?
From: ken emery <ken () cnet com>
Date: Thu, 22 Jan 2004 14:28:05 -0800 (PST)
On Thu, 22 Jan 2004, Brett Watson wrote:
First, yes I know I should call AT&T but I want to know if anyone else sees this problem: I have a customer that is multi-homed to AT&T and WCOM. They accept "default" via BGP from both providers and announce a handful of prefixes to both providers. Given that they receive default, it's just the same as if they had a *static* default to both providers. The customer installed a "network mapping tool" today and suddenly discovered they were seeing RFC1918 addresses in the map (hundreds of them) that were *not* part of the customer's internal network. It turns out that from what we can tell, insightbb.com (an AT&T sub or customer) is probably unintentionally leaking 10/8 and AT&T is propogating that across their network. Since the customer defaults for any "unknown" destination, they're crossing the AT&T network. If my customer had been taking full routing, with appropriate filters of course, they wouldn't be seeing this. But given that they are taking default, they see it. So I just wanted to see if anyone that is defaulting to AT&T is seeing this same problem just to verify that what we're seeing is correct (for my customer's edification). Yes, I'm calling AT&T now :)
Yep, they are sending 10.X.X.X routes to customers. From several places actually, Level3, Comcast (multiple AS's), AT&T, MediaOne, and AccessPoint. bye, ken emery
Current thread:
- AT&T carrying rfc1918 on the as7018 backbone? Brett Watson (Jan 22)
- Re: AT&T carrying rfc1918 on the as7018 backbone? ken emery (Jan 22)
- Re: AT&T carrying rfc1918 on the as7018 backbone? Stephen Fisher (Jan 22)
- Re: AT&T carrying rfc1918 on the as7018 backbone? Chris Adams (Jan 22)
- Re: AT&T carrying rfc1918 on the as7018 backbone? Brett Watson (Jan 22)
- Re: AT&T carrying rfc1918 on the as7018 backbone? Matt Levine (Jan 22)
- Re: AT&T carrying rfc1918 on the as7018 backbone? ken emery (Jan 22)
- Re: AT&T carrying rfc1918 on the as7018 backbone? Stephen Fisher (Jan 22)
- Re: AT&T carrying rfc1918 on the as7018 backbone? ken emery (Jan 22)
- Re: AT&T carrying rfc1918 on the as7018 backbone? Matthew S. Hallacy (Jan 22)
- Re: AT&T carrying rfc1918 on the as7018 backbone? ken emery (Jan 22)
- Re: AT&T carrying rfc1918 on the as7018 backbone? Sean Donelan (Jan 22)
- Re: AT&T carrying rfc1918 on the as7018 backbone? Brett Watson (Jan 22)
- Re: AT&T carrying rfc1918 on the as7018 backbone? Tomas Lund (Jan 22)
- Re: AT&T carrying rfc1918 on the as7018 backbone? Brett Watson (Jan 22)