Digital evidence investigation in QQ software is the current research focus.In order to identify the authenticity and credibility of QQ chat records,the method based on attacking QQ chat records is proposed.Firstly,an...Digital evidence investigation in QQ software is the current research focus.In order to identify the authenticity and credibility of QQ chat records,the method based on attacking QQ chat records is proposed.Firstly,an evaluation model on checking the authenticity of QQ chat records is proposed.The cases on kinds of changing QQ chat records are discussed.The challenge in identifying the authenticity of QQ chat records is raised.Secondly,case study on attacking QQ chat records is proposed to check the relationship between the authenticity of QQ chat records and the difficulty of changing them.A couple of experiments on changing QQ chat records are finished to find how difficult changing records is and whether there are clues left on changing them or not.Finally,a kind of QQ chat forensic process is presented,which can help for digital evidence investigation in the authenticity and credibility of QQ chat records.The practices in QQ forensic cases show that it works well.展开更多
Quantum key distribution(QKD)-based quantum private query(QPQ) is a practical application of QKD, which relaxes the security condition of perfectly concealing a private query to a cheating-sensitive strategy. We propo...Quantum key distribution(QKD)-based quantum private query(QPQ) is a practical application of QKD, which relaxes the security condition of perfectly concealing a private query to a cheating-sensitive strategy. We propose a QPQ protocol based on the delegated QKD scheme(DQKD-based QPQ), in which two almost ‘classical' clients(data user and database owner) can establish a 1-out-of-N oblivious key with the help of a cloud server with full quantum ability. Concretely, the two classical participants in the DQKD-based QPQ only need to access the quantum channel and reorder qubits, and the costly quantum operations, quantum state preparation and measurement are outsourced to a full quantum server in the cloud without leaking participants' privacy. The proposed protocol not only provides a cloud-based framework of QKD-based QPQ, but also obtains better security by a real-time security check, which can protect the security of the database and user against all potential attacks even if the quantum server is assumed to be a powerfully untrusted adversary.展开更多
基金Sponsored by Science&Technology Research Program of the Municipal Education Committee of Chongqing of China(No.KJ110505)Key Project of Science and Technology and Natural Science Foundation Project of CQ CSTC of China(No.cstc2011AC2155 and cstc2011jjA 40031)
文摘Digital evidence investigation in QQ software is the current research focus.In order to identify the authenticity and credibility of QQ chat records,the method based on attacking QQ chat records is proposed.Firstly,an evaluation model on checking the authenticity of QQ chat records is proposed.The cases on kinds of changing QQ chat records are discussed.The challenge in identifying the authenticity of QQ chat records is raised.Secondly,case study on attacking QQ chat records is proposed to check the relationship between the authenticity of QQ chat records and the difficulty of changing them.A couple of experiments on changing QQ chat records are finished to find how difficult changing records is and whether there are clues left on changing them or not.Finally,a kind of QQ chat forensic process is presented,which can help for digital evidence investigation in the authenticity and credibility of QQ chat records.The practices in QQ forensic cases show that it works well.
基金Supported by the National Key R&D Program of China under Grant No 2017YFB0802300the Foundation Science and Forefront Technology of Chongqing Science and Technology Commission of China under Grant No cstc2016jcyj A0571
文摘Quantum key distribution(QKD)-based quantum private query(QPQ) is a practical application of QKD, which relaxes the security condition of perfectly concealing a private query to a cheating-sensitive strategy. We propose a QPQ protocol based on the delegated QKD scheme(DQKD-based QPQ), in which two almost ‘classical' clients(data user and database owner) can establish a 1-out-of-N oblivious key with the help of a cloud server with full quantum ability. Concretely, the two classical participants in the DQKD-based QPQ only need to access the quantum channel and reorder qubits, and the costly quantum operations, quantum state preparation and measurement are outsourced to a full quantum server in the cloud without leaking participants' privacy. The proposed protocol not only provides a cloud-based framework of QKD-based QPQ, but also obtains better security by a real-time security check, which can protect the security of the database and user against all potential attacks even if the quantum server is assumed to be a powerfully untrusted adversary.
