Abstract The rapid growth of network communications has made applications of electronic commerce the future trend of commercial activities. To ensure the effectiveness of transactions, governments put the electronic signature law into practice. They also proposed guiding or assisting projects to encourage or help enterprises and organizations to construct secure electronic environments. Because of the availability and ease of use of information infrastructure, human’s daily life is increasingly digitalized. With the promotion of life education and religious groups, people have gradually accepted the concept of writing down wills before their death, which can reduce conflicts and arguments for inheritance. A legitimate will can be produced with the witness of notaries in the court or the notary public offices. If a testator wishes to modify his will, he must perform again the procedures above. Since, it requires some fees as well as transportation costs for notaries and witnesses, the generation of a traditional will is rather costly. It might also be inefficient for its complicated witnessing procedures. Currently, the electronic Wills Act is under discussions, but not put into practice yet. To date, there are no literatures discussing the issues of digital will. The properties of security, convenience and effectiveness are the most significant reasons why people would like to adopt the digital will mechanism in the future. Based on the mechanisms of public key infrastructure and key escrow systems, we constructed a secure and realistic model for a digital will system which fulfills the above-mentioned properties and is suitable for practical implementation.

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