On Mon, 15 Aug 2005, George Gross wrote: > > I should also point out that AFAICT a DKIM e-mail signature does not > protect against the "revolving door" signature identity problem. It > erronously presumes that all DNS registry entities are not the economic > allies or suppliers for spammers. It would be feasible for such a > registrar to automate the domain name generation process on behalf of its > spammer customers. Once such a domain name's reputation becomes tarnished, > it is discarded and the co-conspirator DNS registrar issues a new one to > take its place. I see this attack (and I suspect that there are others > that one can discover) as a fundemental problem with the proposed e-mail > security architecture.
There's a lot more information available about domain names than about IP addresses, e.g. via whois, via the domain's NS records, etc. This information can be used to bootstrap a reputation in a way that defends against the use of throwaway domains by spammers. Tony. -- f.a.n.finch <[EMAIL PROTECTED]> http://dotat.at/ BISCAY: WEST 5 OR 6 BECOMING VARIABLE 3 OR 4. SHOWERS AT FIRST. MODERATE OR GOOD. _______________________________________________ ietf-dkim mailing list http://dkim.org
