|  | 5.6 | Basic Topologies Used in Networking
| 5.6.6 | Extended star network topology
Mathematical Perspective An extended star topology repeats a star topology, except that each node that links to the center node is, also, the center of another star. Physical Perspective An extended star topology has a core star topology, with each of the end nodes of the core topology acting as the center of its own star topology. The advantage of this is that it keeps wiring runs shorter, and limits the number of devices that need to interconnect to any one central node. Logical Perspective An extended star topology is very hierarchical, and information is encouraged to stay local. This is how the phone system is currently structured.