Out of Date Bogon Prefix

Nick Downey ndowney at mediacomcc.com
Tue Aug 5 12:16:53 CDT 2008

This is an heads-up from the Mediacom Network Operations Center about an
issue we are seeing. We             

were recently given an IP scope from ARIN (American Registry for Internet
Numbers) that still

exists on older Bogon lists many web providers are currently using.

A Bogon prefix is a route that should never appear in the Internet routing
table. A packet routed                                     

over the public Internet (not including over VPN or other tunnels) should
never have a source

address in a Bogon range. These are commonly found as the source addresses
of DDoS attacks.

The IP scope referenced is a 173.x.x.x. This IP scope was on the Bogon list
and was blocked by all  

websites using a Bogon prefix up until February of 2008, when it was
released by IANA (Internet 

Assigned Numbers Authority) for public use and an updated Bogon prefix was
provided. Mediacom

customers that are within this IP range are not able to reach a website
hosted by many organizations. 


Mediacom is individually requesting that these providers update their Bogon
prefix to the most current version

to resolve this issue immediately. We are requesting assistance from this
community to make this issue known
and to advise administrators to update to the most current Bogon list.
We have provided some reference material that many may find helpful in
resolving this issue. 
Bogons are defined as Martians (private and reserved addresses defined by
<http://www.ietf.org/rfc/rfc1918.txt> RFC 1918 <
http://www.faqs.org/rfcs/rfc1918.html> and
<http://www.ietf.org/rfc/rfc3330.txt> RFC 3330 <
http://www.faqs.org/rfcs/rfc3330.html>) and netblocks that have not been
allocated to a regional internet registry (RIR) by the Internet Assigned
Numbers Authority < <http://www.iana.org/> http://www.iana.org/>. IANA
maintains a convenient IPv4 summary page <
http://www.iana.org/assignments/ipv4-address-space> listing allocated and
reserved netblocks.
Please help to spread the word.
Nick Downey
Network Operations Center
Mediacom Communications
Main (800)308-6715
Secondary (515)267-1167
ndowney at mediacomcc.com

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