US Patent 7756937 Network device

A network device is to be connected with a communication network. The network device is capable of executing a communication function by utilizing the communication network. The network device is provided with an input device, a storage, a communication device, and a communication test device. The input device inputs communication setting data for executing the communication function. The storage is capable of storing at least two patterns of the communication setting data. The communication device executes the communication function by utilizing one pattern of the communication setting data stored in the storage. The communication test device tests whether it is possible to execute the communication function by utilizing the other pattern of the communication setting data stored in the storage while maintaining a state where it is possible for the communication device to execute the communication function by utilizing the one pattern of the communication setting data.