Tetsuji Kobayashi

An evaluation of the secret voting method using a one-way homomorphic function for network meetings

This paper proposes and evaluates a secret voting method using a one-way homomorphic function for network meetings. A network meeting can be performed by using communication media such as emails, phones, cell phones, etc. The proposed secret voting method does not need an anonymous communication channel, and the secure voting application software is used for checking the correctness of the voting content at each terminal of each voter. The proposed secret voting method is compared with the method using blind signatures and the method using the homomorphic encryption. The secret voting method using the one-way homomorphic function is better from the viewpoint of simplicity than the secret voting method using the homomorphic encryption.

A student ID system using a cell phone and its evaluation

This paper proposes a method to construct a student ID (identification) system using a cell phone. The student ID data are stored in the server. Each student receives the student ID data in each cell phone. The cell phone displays the character data (name, affiliation, etc.), the face image and the two-dimensional symbol. As the face image displayed on the cell phone is large enough in comparison with the photograph size of the conventional ID card, the precision is improved when the examiner compares the displayed face image to the live face. The student ID can be used not only when the examiners terminal can communicate with the server, but also when it cannot communicate with the server. The cost for issuing or reissuing a student ID by using the proposed method is very low in comparison with the conventional student ID card. The prototype has been implemented and evaluated.

The ID system using a cell phone with the verification and security

ID (identification) cards are used for proving the identity of each person. In many cases, the ID card is realized by using an IC plastic card. The student ID (identification) card is used for proving the studentship of each student in a college or a university. This paper proposes a method to realize a student ID electronically on the screen of a cell phone. The original student ID data are stored in a personal computer (PC) of the administrator. The student ID is realized by using a protected file sent to each students cell phone. After receiving the student ID, each student can use it without communicating the PC of the administrator. The validity of the student ID using a cell phone is verified by the inspectors cell phone including the verification software. The proposed student ID has a merit that it can be used for most of handset models of cell phones and cell phone carriers. The prototype of the student ID using a cell phone is constructed and evaluated. The proposing student ID system can be extended for the general purpose ID system such as a company ID card system.

Security improvement of the ID system using a cell phone

A personal identification method that is called as the electronic ID is proposed by using a cell phone. The cell phone displays a face image, character data and a two-dimensional including personal identification data. Although plastic cards, magnetic stripe cards and smart cards are used as ID (identification) cards, the risks to lose these cards are large. A cell phone of the electronic ID can securely display all of the identification data on its color display. The prototype of the electronic 10 system using a cell phone, a Web server and a managers portable computer to identify each user is implemented and experimented.