A dual use blockstream cipher is provided with a first key section and a data section. In this case, this MP3 part is mute-reproduced in a period that extends from the first reproducing start position to a timing corresponding to the second reproducing start position. The subscriber data server handles an incoming call request, from a first user-terminal connected to a first virtual private network, to establish a connection between the first user-terminal and the second user-terminal that is connected to a second virtual private network. The top bracket assembly includes a top bearing coupled to a top bracket and a top hinge support coupled to the top bearing.