Abstract: Embodiments of the present invention are directed to methods and systems for generating and revoking, as well as validating, certificates used to protect communications within networks while maintaining privacy protection. In the context of a method, certificate generation and revocation with privacy preservation comprises determining a secret value to be used by a certificate authority and an entity; constructing a key tree based on the secret value, wherein the leaves of the key tree represent derived keys for the certificates for the entity; and generating certificates for the entity based in part on the key tree leaves. The method further comprises determining that one or more of the certificates should be revoked; determining a minimum key node set that covers the certificates to be revoked; adding the minimum key node set to a certificate revocation list; and providing the certificate revocation list to one or more entities. Corresponding apparatuses and computer program products are also provided.

Abstract: A method for switching service channels in a vehicular environment is provided for performing communications between a user unit and a service provider unit according to a switch ratio between a service channel and a control channel in a multi-channel switching wireless communication environment. The method includes the following steps. In response to a message indicating that the service provider unit uses an access mode of an extended service channel, whether information of the switch ratio is stored in service information of the user unit is searched in the user unit according to geographical information of the service provider unit. If the information of the switch ratio is stored in the service information of the user unit in the searching step, the user unit is set accordingly to enter the access mode of the extended service channel.

Abstract: A method for switching service channels in a vehicular environment is provided for performing communications between a user unit and a service provider unit according to a switch ratio between a service channel and a control channel in a multi-channel switching wireless communication environment. The method includes the following steps. In response to a message indicating that the service provider unit uses an access mode of an extended service channel, whether information of the switch ratio is stored in service information of the user unit is searched in the user unit according to geographical information of the service provider unit. If the information of the switch ratio is stored in the service information of the user unit in the searching step, the user unit is set accordingly to enter the access mode of the extended service channel.

Abstract: A fleet maintenance method for generating a suggested speed for each vehicle in a fleet to maintain the vehicle in the fleet is provided. In the fleet maintenance method, vehicles are clustered into a plurality of sub-fleets, and in each sub-fleet, one vehicle is selected as a leader vehicle and the other vehicles are considered as member vehicles. Besides, a position coordinate and a speed of each vehicle in each sub-fleet are obtained, and the position coordinate is converted into a corresponding linear coordinate. In addition, a sub-fleet gravity center of each sub-fleet and a fleet gravity center of the entire fleet are calculated according to the linear coordinates. Moreover, a suggested speed of each leader vehicle is generated according to a gravity center distance of the leader vehicle, and a suggested speed of each member vehicle is generated.

Abstract: A fleet maintenance method for generating a suggested speed for each vehicle in a fleet to maintain the vehicle in the fleet is provided. In the fleet maintenance method, vehicles are clustered into a plurality of sub-fleets, and in each sub-fleet, one vehicle is selected as a leader vehicle and the other vehicles are considered as member vehicles. Besides, a position coordinate and a speed of each vehicle in each sub-fleet are obtained, and the position coordinate is converted into a corresponding linear coordinate. In addition, a sub-fleet gravity center of each sub-fleet and a fleet gravity center of the entire fleet are calculated according to the linear coordinates. Moreover, a suggested speed of each leader vehicle is generated according to a gravity center distance of the leader vehicle, and a suggested speed of each member vehicle is generated.

Abstract: A gateway service method applied in a gateway device of OSGi is provided. The method includes obtaining at least an identification information of at least a client device; communicating with at least a service supplier according to the identification information; obtaining at least an OSGi bundle corresponding to the client device and supplied by the service supplier; and processing the OSGi bundle to supply service to the client device.

Abstract: Disclosed is a communication routing apparatus and method via navigation system, which is applicable to mobile networks. The apparatus comprises a routing protocol mechanism and a navigation module having map information and a navigation path calculating unit therein. The routing protocol mechanism inputs the location information of a source and a destination to the navigation path calculating unit. Through the map information, the navigation path calculating unit suggests a communication route between the mobile nodes from the source to the destination. With the help of the communication route, the routing protocol mechanism handles the route discovery message, the route reply message and the route error message from the source to the destination.