I cleared my emails too enthousiastically so I don't have the exact question anymore but I saw this morning that somebody asked for a document that compares RSA, ECC and DSA. Maybe the following links could be useful. Kind regards, Lies. D.B. Johnson, A. Menezes, http://www.certicom.ca/research/wecdsa.html M.J.B. Robshaw and Yiqun Lisa Yin, http://www.rsasecurity.com/rsalabs/ecc/elliptic_curve.html