Through cryptanalysis of the improved scheme of a generalized group-oriented threshold signcryption schemes,it is found that the improved scheme can effectively resist conspiracy attack and forgery attack,but does not...Through cryptanalysis of the improved scheme of a generalized group-oriented threshold signcryption schemes,it is found that the improved scheme can effectively resist conspiracy attack and forgery attack,but does not have semantic security and public verification function,and sends threshold signcryption by the secret secure channel,which increases the communication costs and potential safety hazards of the system.A new group-oriented publicly verifiable threshold signcryption scheme is proposed on the basis of the improved scheme,the new scheme overcomes the drawbacks of the improved scheme,which not only provides with semantic security and public verification function,but also can send threshold signcryption by the public channel.展开更多
A novel broadcast encryption scheme for group communication scenarios in distributed networks is presented. In the scheme, anyone is allowed to encrypt a message and distribute it to a designated group. Each member in...A novel broadcast encryption scheme for group communication scenarios in distributed networks is presented. In the scheme, anyone is allowed to encrypt a message and distribute it to a designated group. Each member in the designated group has the ability to independently decrypt a ciphertext. In contrast to traditional broadcast encryption, all the valid receivers in the proposed scheme compose the designated group. To take advantage of this property, a tab for the group is set and the matching private key for each member is generated. In addition, before decrypting a ciphertext, anyone in the scheme can verify the ciphertext, to ensure that the ciphertext is correct. This property is very important for large-scale group communication, as the gateway can filter incorrect ciphertext and alleviate the receiver＇s workload. Finally, a proof in the random oracle model is given, to show that the proposed scheme is secure against the adaptively chosen ciphertext attack.展开更多
基金Supported by the National Natural Science Foundation of China(No.61179026)the Fundamental Research funds for the Centeral Universities(No.3122013K001)
文摘Through cryptanalysis of the improved scheme of a generalized group-oriented threshold signcryption schemes,it is found that the improved scheme can effectively resist conspiracy attack and forgery attack,but does not have semantic security and public verification function,and sends threshold signcryption by the secret secure channel,which increases the communication costs and potential safety hazards of the system.A new group-oriented publicly verifiable threshold signcryption scheme is proposed on the basis of the improved scheme,the new scheme overcomes the drawbacks of the improved scheme,which not only provides with semantic security and public verification function,but also can send threshold signcryption by the public channel.
文摘A novel broadcast encryption scheme for group communication scenarios in distributed networks is presented. In the scheme, anyone is allowed to encrypt a message and distribute it to a designated group. Each member in the designated group has the ability to independently decrypt a ciphertext. In contrast to traditional broadcast encryption, all the valid receivers in the proposed scheme compose the designated group. To take advantage of this property, a tab for the group is set and the matching private key for each member is generated. In addition, before decrypting a ciphertext, anyone in the scheme can verify the ciphertext, to ensure that the ciphertext is correct. This property is very important for large-scale group communication, as the gateway can filter incorrect ciphertext and alleviate the receiver＇s workload. Finally, a proof in the random oracle model is given, to show that the proposed scheme is secure against the adaptively chosen ciphertext attack.
