What is synchronous fiber optic network
Synchronous Optical Network, or SONET for short, is the physical layer standard for Optical fiber transmission first proposed by Bellcore in the mid-1980s. It is ANSI standardized and recommended by CCITT for worldwide distribution. SONET as a physical network of global communication systems can be viewed in the same way that Ethernet as an organizational network communication system is viewed with a twisted pair LAN. This is a potentially global network with standard data transfer rates over fiber optics and is widely accepted worldwide. SONET brings together the world's telephone companies.
A multiplexing channel on a synchronous circuit. This structure provides a way to know exactly on which particular channel frames are located and to retrieve those frames without diverting the entire multiplexing signal. In this way, there are different types of channels (low speed and high speed) on the network, and users can make a variety of routing choices.
Fiber-optic transport standards allow the interconnection of products from different vendors and systems from communication companies.
The cables that make up SONET are laid between SONET multiplexing devices. SONET specifies specifications for fiber optic cables and light generation, as well as data multiplexing and frame generation. SONET signals carry data and control information in the form of synchronous data streams. Control information is embedded in the signal and is considered OVERHEAD. The auxiliary operation of SONET signal includes the following parts:
Section assist operations handle frame generation and error monitoring. All devices on the line will use this feature.
Line auxiliary operations Monitor line status.
Path assist operations are used to control signal transmission and error monitoring between network endpoints (path terminal devices).
The SONET specification also specifies how low-speed signals such as T1/E1 and T3/E3 are inserted for synchronous transmission. SONET service breaks the T3(45Mbps) limit. Its basic optical transmission rate of 51.8 Mbps is equivalent to one T3 line or 28 T1 lines. The high-grade OC-48 optical carrier can be equivalent to 1344 T1 or 48 T3 lines. Initially, THE OC-3 transmission rate will provide customer service to the telecommunications office, and high transmission rate applications will grow in the 1990s.
Fiber optic cables provide tremendous bandwidth, which will bring the cost of wide area networks down to affordable levels. Many companies will build networks that allow remote users to access data at the same speed as local users to enhance remote users' ability to communicate and compete. Copper wire does not offer the same scalability as optical cable because it requires too many copper wires to provide the same bandwidth.
