- From: James A. Donald <jamesd@echeque.com>
- Date: Wed, 21 Jun 2006 09:11:30 +1000
- To: public-usable-authentication@w3.org
-- > If you're on this list and care at all about Secure > Chrome and Secure MetaData, and about your colleagues > who also care about Secure Chrome and Secure MetaData, > you'll refrain from discussing other topics, even if > you have the most brilliant insight in the world on > them. I think you are guilty of premature optimization. One question surely is: what problem does one want to solve using Secure Chrome and Secure MetaData? Being engineers, our natural approach is to break the problem down into small pieces. We must, however, not break this problem down into pieces that cut across the security perimeter, at least not until a security perimeter actually exists. Security is as strong as its weakest link, and is commonly attacked on the link between applications. PKI is a fort with a wall on only one side. Let us not repeat the error yet again. The browser's most severe insecurities are that one receives email that purports to be from a web site where one has a login relationship, and that email contains browser links that purport to be from the domain that originated the email. Any problem that is declared to be off topic or out of scope, is usually the problem whereby security comes under attack. Thus SPF is dying in large part because filtering was declared to be out of scope, whereupon spammers became the earliest and most enthusiastic adopters of SPF. Security solutions whereby the account holder notifying the bank is in scope, but the bank notifying the account holder is out of scope, are likely to fail similarly. Security improvements in email and the browser have to be integrated and talk to each other - for example browser login information has to be available to check email authenticity, or else we have to develop some new push mechanism without the problems of email. Verisign's proposed Secure Internet Letterhead is an attempt to provide an integrated solution, since to be useful the proposed letterhead must show both on the browser and on the email client, but this proposal is likely to fail because it amounts to an outsider who has little relationship to either party providing trust, and charging a fee for that trust. To solve the network effect problem for Secure Internet Letterhead, which is surely on topic for this list, Phillip Hallam-Baker, a man with some influence at Verisign, has suggested some form of integration between SIL and DK, which, to be useful, would involve the browser making use of DK information, so that one could have some kind of display on both web and email that vouched for the equivalence of the email and the web site, without Verisign necessarily providing, and charging for, evidence that both come from a legitimate business. --digsig James A. Donald 6YeGpsZR+nOTh/cGwvITnSR3TdzclVpR0+pr3YYQdkG xIuvO0+BbWEM/ch4Y8Ar+kJjEw9XmY+qRFclLVsz 4lCmsIfbfiu1XE1vzsk7OwMkqimwjp9n0AN27G/ZB
Received on Tuesday, 20 June 2006 23:13:08 UTC