An identity-based broadcast signcryption scheme and its application to medical images sharing

. An Identity-based Broadcast Signcryption Scheme and Its Application to Medical Images Sharing Dang Thu Hien Faculty of Information Technology University of Engineering and Technology. need of secure and authenticated data transmission is more and more important and critical. Since the birth of public key cryptography in 1970s, the requirements of confi dentiality and authenticity. of more than к users can collude to recover the polynomial and break the system. Another scheme based on ID-based encryption algorithm of Boneh-Franklin [BF01] was introduced and analyzed