ation as follows:</p>

<p>y^2 mod p = x^3 +ax + b mod p</p>

<p>The second form is those defined over a binary field F2^m where the elements of the field are integers of length at most m bits. For this form the elliptic curve equation is modified to:</p>

<p>y^2 + xy = x^3 + ax^2 + b (where b != 0)</p>

<p>Operations in a binary field are performed relative to an <b>irreducible polynomial</b>. All such curves with OpenSSL use a trinomial or a pentanomial for this parameter.</p>

<p>Although deprecated since