Abstract: The invention is directed to a method for applying a certificate suitable for a portable telephone belonging to a user, wherein the portable telephone comprises a telephone number. The method comprises steps of generating a user key pair in the portable telephone, wherein the key pair comprises a user public key information and then transmitting an applying packet from the portable telephone to a certificate authority through a switching center by using a short message service, wherein the applying packet comprises at least the user public key information. The user is verified according to the telephone number received by the certificate authority from the switching center. A certificate packet is generated by the certificate authority, wherein the certificate packet comprises at least a serial number and a certificate authority signature. The certificate packet is transmitted to the portable telephone according to the telephone number by using the short message service.

Abstract: The invention discloses a communication system for assisting a user for retrieving geography-associated multimedia information, and the communication system comprises a data processing device and several mobile communication devices. The data processing device receives a first request information including a location term and a time term from a terminal device of the user, and broadcasting a second request information, based on the time term, to the mobile communication devices located within a region relative to the location term. The data processing device receives responding messages and captured audio and/or video data from the mobile communication devices accepting the second request information, and transmitting a location-related information to the terminal device based on the responding messages. The user transmits responding information responsive to the location-related information to the data processing device via the terminal device.

Abstract: The invention discloses an event announcing system. The event announcing system comprises a portable electrical apparatus, a network, and a server. The portable electrical apparatus comprises an image capturing module, a positioning module, a time module, and a processing module. When the image capturing module captures an image information related to an event, the positioning module receives a positioning information and the time module receives a time information. The processing module is used for generating an announcing signal according to the image information, the positioning information, and the time information. When the server receives the announcing signal via the network, the server validates the announcing signal according to a validating rule and selectively generates an event report according to the announcing signal.

Abstract: A logging system and method based on a one-way hash function are described. The system includes a user system, a trusted third party, and a verifier. The method includes the following steps. The user system records a log file and initializes a message authentication code key and an image code. When the verifier requests the user system for a logging unit corresponding to an operation history, the user system uses a one-way hash function to calculate a check value and returns the check value and an image code sequence. The verifier then verifies the integrity of the check value and the image code sequence through the trusted third party. The trusted third party checks if the image code sequence obtained by the hash calculation equals to the check value through the one-way hash function, so as to verify that the log file of the user system has not been modified.

Abstract: The invention is directed to a method for applying a certificate suitable for a portable telephone belonging to a user, wherein the portable telephone comprises a telephone number. The method comprises steps of generating a user key pair in the portable telephone, wherein the key pair comprises a user public key information and then transmitting an applying packet from the portable telephone to a certificate authority through a switching center by using a short message service, wherein the applying packet comprises at least the user public key information. The user is verified according to the telephone number received by the certificate authority from the switching center. A certificate packet is generated by the certificate authority, wherein the certificate packet comprises at least a serial number and a certificate authority signature. The certificate packet is transmitted to the portable telephone according to the telephone number by using the short message service.

Abstract: A file access and management mechanism over Internet, and a method for distributing a file in arbitrary storage spaces and maintaining file security in the storage spaces are introduced herein. In addition, a method for maintaining file availability in the aforementioned storage spaces, a conversion manner between a network address and a virtual storage space address, and an addressing manner for determining addresses for placing file fragments are also introduced. The above storing manner also considers parameters at least including truth, availability, and size for choosing the storage space. And the present invention further provides a method for retrieving and deleting file fragments.