For the algorithms that NIST recognizes and approves, the doc linked below has some strength comparisons in tables near page 60
http://csrc.nist.gov/publications/nistpubs/800-57/sp800-57-Part1-revised2_Mar08-2007.pdf Bruce A Rich brich at-sign us dot ibm dot com From: Bradford Wetmore <[email protected]> To: Weijun Wang <[email protected]> Cc: "[email protected]" <[email protected]>, OpenJDK <[email protected]> Date: 10/23/2011 10:47 PM Subject: Re: Is there an algorithm that computes the strength of a digest alg? Sent by: [email protected] I don't know of anything like that. As Michael points out, key Lengths by themselves are not always a good indicator of relative stength. BTW, JSSE hard-codes the choices. Brad On 10/23/2011 6:52 PM, Weijun Wang wrote: > Hi Andrew > > I need a method > > boolean isWeakerThan(String a1, String a2) > > so that isWeakerThan("MD5", "SHA1") returns true and > isWeakerThan("SHA-256", "SHA1") returns false. I know you have done a > lot of constraints works in JDK 7. Do you have an existing one? > Otherwise, I plan to manually assign a value to each known algorithm and > compare it. > > Thanks > Max
