Computer Network Topology

More & more computer networks use wireless methods to move knowledge from process to another, however lots of networks still use some type of cabling (Copper or Fiber Optic) to connect systems. The way that cable & hardware, or wireless signals connect to another to form a network is called the Network Topology. Historical network topologies include Bus, Ring, & Star, while modern topologies include Hybrid, Mesh, Point-to-Multipoint, & Point-to-Point.

Historical Topologies

Bus: A bus topology makes use of a single bus cable that connects all of the computers in a line, & knowledge goes out on the whole bus. To prevent knowledge from reflecting at the ends of the cable & generating unnecessary traffic a bus topology needs terminators at each finish of the cable.

Ring: A ring topology is similar to a bus topology except that it connects all computers with a central ring cable, so there are no ends to the bus & it does not need termination. The knowledge flows in a circle from computer to the next in the same direction.

*If a cable is broken at any point in a bus or ring topology the whole network stops working. The broken ends in a bus topology create reflection of knowledge between the still connected computers because the termination point is no longer connected to the network. A broken cable in a ring topology breaks the circuit & stops the flow of knowledge.

Star: A star topology makes use of a central connection point for all computers on a network, which offers fault tolerance not available with bus or ring topologies. If any connection is broken in a star topology the other systems on the network are not affected & are still able to send & get knowledge.

Modern Topologies

Hybrid: A hybrid topology combines the features of the bus & ring topologies with the star topology by shrinking the actual bus or ring in to a small box called a hub which serves the purpose of the central connection point or star. Star-bus & star-ring topologies physically look like star topologies however the actual electronic schematics act like a bus or ring. Any topology that combines a physical topology with an electronic signaling topology is called a Hybrid Topology.

Mesh: A mesh topology connects every method to every other method in a network by or more routes, sometimes requiring particular routes to traverse through another method in the mesh network. A partially meshed topology includes at least systems with redundant connections, & every computer does not need to connect to every other computer. In a fully meshed topology every computer connects directly to every other computer. A meshed topology is robust & if a single connection is broken the systems are not affected, however because of the complexity of connecting cables to & from every computer in a network the mesh topology is not practical for cabled networks & will usually only be seen in wireless networks.

Point-to-Multipoint: A point-to-multipoint topology includes a single computer method that is used a common source through which all of the other systems on the network converse. Similar to the star topology in that there is a central point, the difference is in the gizmo that exists in the midst of the network. The middle of the star topology is small over a path for the knowledge to travel to the various systems, whereas the middle of a point-to-multipoint topology includes an actual hub, router, or switch which controls the knowledge flow to the various other systems in the network. The point-to-multipoint topology is sometimes often called a Tree Topology & is called an Infrastructure Network.

Point-to-Point: A point-to-point topology includes computers directly connected together with no need for a central hub, router, or switch. Point-to-point topologies are present in both wired & wireless networks. They are known as Ad-hoc or Peer to Peer networks.