montel is the newly hired it administrator at a long-established company. in studying its it infrastructure, he discovers that the main office is connected to four other branch offices in their large city, with each office being linked to the others by dedicated leased lines that allow for direct communications from one location to the next. this mesh network is used only by the company. montel tells the company's cio that he has discovered an issue with this design. compared to a virtual private network (vpn), what main drawback does montel report?