spf-discuss
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Re: Security Paper on forgery bounce DDoS

2004-04-18 04:57:37

On Apr 18, 2004, at 3:02 AM, Hector Santos wrote:

The primary DNS servers are going to be shocked with all the failed requests with everyone and their grandma doing redundant SPF domain lookups when the
odds are going to be very high the request will fail.

I don't even know where to begin to explain how silly that line of thought is.

The relays.ordb.org nameservers are using less than 25Mbit per second. Combined! When the traffic peaks! Everyone and their grandma are doing ORDB lookups and unlike SPF the requests are not very well distributed.

For the notion that the primary servers will get "shocked". Please... The relevant referrals from the primary servers are likely already cached, and if not then it'll be a drop in the ocean compared to other. DNS traffic. (Or to continue the comparison to ORDB, then the traffic to the ordb.org nameservers is negligible.

I'm not a DNS administrative expert, but I still predict a network bandwidth overhead
problem developed.

Really? And how would that be? Even a dozen, heck, two dozens of DNS requests still only consume a fraction of the bandwidth that your average SMTP transaction does.


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