The physical topology defines the physical connections between the devices and the shape that these connections form. In most cases, it is easy to see this shape. In other cases, such as the way in which a star is usually implemented in an enterprise, it is not quite as obvious.
This section covers all of the common physical topologies, giving special attention to their respective advantages and disadvantages. Many of the topologies, such as bus, ring, star, mesh, and hybrid, are most commonly applied to LAN design. Point-to-point and point-to-multipoint topologies are more commonly applied in WAN design. They describe the manner in which routers that host WAN connections are designed.