blocking unallocated subnets
Rob Thomas
robt at cymru.com
Fri Dec 2 20:04:38 UTC 2005
Hi, John.
] I work for a large email provider and we've run into trouble
] delivering mail to certain sites after bringing up new servers in a
] recently allocated subnet of 72/8. Apparently, some folks decided it
] would be a good policy to protect their nameservers from ddos attacks
] to silently drop requests from unallocated subnets. So they obtained
] a list of subnets at some point in the past, deployed it and then
] never updated it.
This is why we recommend to those who filter unallocated and bogon
space to keep current with lists such as the sundry formats found
here:
<http://www.cymru.com/Bogons/>
Another option is to automate the updates and leave the hard work
to us! :) Consider peering with the Bogon route-servers, located
throughout the globe thanks to the kind donation of hosting from
several folks.
<http://www.cymru.com/BGP/bogon-rs.html>
Thanks,
Rob.
--
Rob Thomas
Team Cymru
http://www.cymru.com/
ASSERT(coffee != empty);
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