protected void StartSA(PeerSecAssociation sa) {
SecurityControlMessage scm_reply = new SecurityControlMessage();
scm_reply.Version = Version;
scm_reply.SPI = sa.SPI;
scm_reply.Type = SecurityControlMessage.MessageType.Cookie;
scm_reply.LocalCookie = CalculateCookie(sa.Sender);
ICopyable to_send = new CopyList(Security, SecureControl, scm_reply.Packet);
_rrman.SendRequest(sa.Sender, ReqrepManager.ReqrepType.Request,
to_send, this, sa);
}