Abstract: A shock absorber has a first and second end surfaces opposite to each other in an axial direction, and a plurality of connection surfaces. The first end surface is an N-sided polygon (N is an integer of 3 or more and the second end surface is an M-sided polygon (M is an integer of 4 or more and more than N). (M?N) vertices are provided at intermediate positions in the axial direction on a circumferential surface defined by the plurality of connection surfaces. From the vertices, one first ridgeline reaches one vertex of the first end surface and two second ridgelines reach a corresponding one of two vertices of the second end surface. The remaining vertices are connected to each other by (2×N?M) third ridgelines. The first ridgeline, the second ridgelines, and the third ridgelines define the plurality of connection surfaces.

Abstract: A satellite link is dynamically assigned in a communication system having a plurality of clients, each client having a unidirectional satellite receiving means and a bi-directional network communication means. Unique information of each client is stored at the managing server within a service provider. A client utilizes its network communication means to send a request to the managing server. The managing server then allocates an IP address to the client's satellite receiving means, and a satellite link is established between the client's satellite receiving means and the managing server based upon the stored unique information of the given client. The assigned IP address corresponds to the assigned satellite link, and the assigned IP address is sent from the managing server to the client utilizing the client's directional network communication means.