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May I note that at least one reference from a major government agency (U.S. NIST SP 800-131A, <span class="url">csrc.<b>nist</b>.gov/publications/<b>nist</b>pubs/800-131A/<b>sp800-131A</b>.pdf</span> ) states that for DH to be "Acceptable" as of Jan 1, 2011, the |p| must be >= 2048 bits, with a |q| of >= 224 bits. 1024 bits <= |p| < 2048 bits and 160 bits <= |q| < 224 bits is listed as "Deprecated" through Dec 31, 2013.<br><br>If we plan on moving to Elliptical Curve prior to 2014, then I don't have a major issue with 1536 bit DH, but if that's not fairly certain, I too would urge a shift to at least a 2048 bit |p| and at least a 224 bit |q| value on the DH side.<br><br><br>Alternately, would it be practical to devote a bit to "security level", so that can be negotiated also, for those cases where larger keys is a major issue - that will also put the framework in place for future elliptical curve algorithms.<br> </div></body>
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