[94021] in North American Network Operators' Group
cold-potato at L3/Chi into UU?
daemon@ATHENA.MIT.EDU (Bradley Urberg Carlson)
Sat Jan 6 14:52:30 2007
To: nanog@merit.edu
From: Bradley Urberg Carlson <buc@visi.com>
Date: Sat, 6 Jan 2007 13:51:00 -0600
Errors-To: owner-nanog@merit.edu
In Chicago, L3 appears to be routing some traffic to UU directly, but
for some other UU destinations, L3 is handing-off to UU via New York:
trace from L3/Chi to 209.98.0.2 (AS8015 via 701) is carried to UU via
New York (edited):
> 1 ae-1-53.bbr1.Chicago1.Level3.net (4.68.101.65) 8 msec
> 2 as-4-0.bbr2.NewYork1.Level3.net (64.159.0.238) 20 msec
> 4 mci-level3-te-newyork1.Level3.net (4.68.110.234) 20 msec
> 8 visi-gw.customer.ALTER.NET (157.130.98.2) [AS701 {ALTERNET}] 32
> msec
Oddly, a L3/Chi trace to the last hop above within AS701 (157.130.98.2)
enters UU immediately in Chicago, taking the shorter path to
Minneapolis:
> 1 ge-7-0-0-56.edge1.Chicago1.Level3.net (4.68.101.173) 0 msec
> 2 0.so-0-3-0.BR2.CHI13.ALTER.NET (204.255.168.117) [AS701 {ALTERNET}]
> 0 msec
> 6 visi-gw.customer.ALTER.NET (157.130.98.2) [AS701 {ALTERNET}] 8 msec
UU support has verified that AS8015 prefixes are advertised at UU's
L3/Chi peering point; and L3 support reports this is "routing as
designed". I would guess that UU requires its peers to use hot-potato
routing, so I'm at a loss as to what kind of traffic engineering is
being used.
--
Bradley Urberg-Carlson
VISI Network Operations; pgp keys avaialble at http://www.keyserver.net/
