Fiber Optic network topology, synthesis, and network-realization

Fiber Access Topologies: Star, Ring (or Bus), and Tree. Several topologies are being used for the optical fiber cable network that connects CO to CP. These topologies are: Star, Ring (or Bus), and Tree topologies. Star topologies are having separate connection for each subscriber. In the ring topologies the subscribers are sharing the single optical line. Tree type connections are have individual connections from CP to Aggregation Nodes, which share connection to the CO. There are Passive and Active types of networks of Tree and Ring topology. In Passive Optical Network, passive equipment is being used that does not require any power. Multiplexing is being deployed on the physical layer through passive optical combiners/splitters and optical filters. Active Optical Network is being powered and is multiplexing on high layers (Ethernet or IP). In Tree topology, Active Network is being deployed with regeneration of a shared TDM link. While it creates a risk of ONUs malfunctioning, it can be avoided in Passive network by using passive Optical ADD/Drop Multiplexers. Note that it requires optics deployment that might be expensive.