Abstract: A power management method for a USB system comprises the steps of: detecting a connecting condition between the USB host and the USB device, reading a descriptor of the USB device, monitoring status of the USB host, selecting an operating mode of the USB device according to the status of the USB host, and selecting a corresponding transmission type via a USB port to transmit a control signal to the USB device so as to switch the operation mode of the USB device.

Abstract: A system for transmitting data in a virtual WAN comprises a plurality of routers, and each router comprises at least one connection port, a network status receiver and a redirection-processing unit. The network status receiver is configured to obtain bandwidth utilization information of other routers through the connection port. The redirection-processing unit is configured to determine whether the router needs to conduct a redirection and to establish a feasible redirection path based on the bandwidth utilization information of other routers.

Abstract: The present invention discloses a method of bandwidth management, which is used in network transmission, including two main steps of setting a user-level bandwidth and setting an application-level bandwidth. At the first step of setting a user-level bandwidth, firstly, the method provides a IP address for the master user, and secondly, provides at least one IP address for the at least one slave user, and then assigns a primary bandwidth to the IP address for the master user and at least one secondary bandwidth to at least one slave user's IP address accordingly. At the second step of setting an application-level bandwidth, the method executes at least one Internet application, and assigns at least one application bandwidth to at least one Internet application accordingly. At least one Internet application is provided. The setting and assignment of the primary bandwidth and the secondary bandwidth mentioned above could be performed in Graphics Interface, which is friendly to users.