name servers all in one AS

Daniel Senie dts at
Sun May 27 15:17:15 UTC 2001

Lookup on reveals a response of 4 name servers:


All 4 of these are in AS 1673.

This situation has existed for a long time. CNN has their actual servers 
multihomed, and (I think) uses Akamai for content delivery. However, the 
core name servers remain on a single AS, so any routing problem within that 
AS, or peering issues affecting that AS will result in CNN.COM disappearing.

Microsoft appears to have spread their DNS servers across multiple ASs 
after their disappearing act a while back. Though I've seen issues with 
CNN.COM reachability affected by ANS.NET issues as far back as 3 years ago, 
their DNS strategy remains unchanged.
Daniel Senie                                        dts at
Amaranth Networks Inc.          

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