UDP DoS mitigation?
ernst at easystreet.com
Fri Dec 12 12:15:16 CST 2008
We've had an increasing rate of DoS attacks that spew tens-of-thousands of
small UDP packets to a destination on our network. We are getting roughly
2x our entire normal pps across all providers through one interface, or
about 4x normal through the individual interface. The Cisco
7206VXR/NPE-G1 CPU melts (>95% load vs 15% average, 20% normal peak) when
I'm using CEF and ip-route-cache flow on the outside interface. Unicast
RPF is also enabled on the interface. Unicast RPF in conjunction with a
BGP black-hole generator handles TCP attacks fairly well.
- Are there any knobs I should be turning in the Cisco config to help with
- Are there any platforms that deal with high PPS/small packet more
We are looking at a network refresh and aren't locked into Cisco as a
vendor (although our current IP network consists entirely of Cisco gear).
Our current aggregate (all providers, in- plus out-bound) bandwidth is
~500Mbs, but projected growth is 1Gbs within the year.
More information about the NANOG