public override void Initialize()
{
_data = new byte[64];
_dataSize = 0;
_totalLength = 0;
_abcd = new ABCDStruct();
//Intitial values as defined in RFC 1321
_abcd.A = 0x67452301;
_abcd.B = 0xefcdab89;
_abcd.C = 0x98badcfe;
_abcd.D = 0x10325476;
}