Optical networking involves the signal transmission using light over fiber optic cable. SONET, synchronous optical networking, uses a number of different sized optical circuits to meet the bandwidth needs of organizations.
Optical circuits range in size from OC-1 to OC192. An OC unit is defined as 51.8Mbps. An OC-1 carries up to 51Mbps, an OC-3 carries 155.4Mbps. Commonly used optical circuit sizes include OC-1, OC-3, OC-12, OC-48, OC-96 and OC-192. An OC-192 equates to 9.9Gbps and is now widely used. An OC-768 circuit, providing 39.7Gbps is now available. As the need for bandwidth increases, more of these large optical circuits will be deployed
