A new extended meta model of traceability is presented. Then, a formalized fine-grained model of traceability is described. Some major issues about this model, including trace units, requirements and relations within ...A new extended meta model of traceability is presented. Then, a formalized fine-grained model of traceability is described. Some major issues about this model, including trace units, requirements and relations within the model, are further analyzed. Finally, a case study that comes from a key project of 863 Program is given.展开更多
Democratic group signatures (DGSs) attract many researchers due to their appealing properties, i.e., anonymity, traceability and no group manager. Security results of existing work are based on decisional Diffie-Hel...Democratic group signatures (DGSs) attract many researchers due to their appealing properties, i.e., anonymity, traceability and no group manager. Security results of existing work are based on decisional Diffie-Hellman (DDH) assumption. In this paper, we present a democratic group signature scheme based on any gap Diffie-Hellman (GDH) group where DDH problem is easily but computational Diffe-Hellman (CDH) problem is hard to be solved. Besides the properties of ordinary DGSs, our scheme also provides the property of linkability, i.e., any public verifier can tell whether two group signatures are generated using the same private key. Security properties of our scheme employ a new and independently interesting decisional product Diffie-Hellman (DPDH) assumption which is weaker than DDH one.展开更多
文摘A new extended meta model of traceability is presented. Then, a formalized fine-grained model of traceability is described. Some major issues about this model, including trace units, requirements and relations within the model, are further analyzed. Finally, a case study that comes from a key project of 863 Program is given.
基金the National Natural Science Foundation of China (Nos. 60703031, 60703004, 60673076)
文摘Democratic group signatures (DGSs) attract many researchers due to their appealing properties, i.e., anonymity, traceability and no group manager. Security results of existing work are based on decisional Diffie-Hellman (DDH) assumption. In this paper, we present a democratic group signature scheme based on any gap Diffie-Hellman (GDH) group where DDH problem is easily but computational Diffe-Hellman (CDH) problem is hard to be solved. Besides the properties of ordinary DGSs, our scheme also provides the property of linkability, i.e., any public verifier can tell whether two group signatures are generated using the same private key. Security properties of our scheme employ a new and independently interesting decisional product Diffie-Hellman (DPDH) assumption which is weaker than DDH one.