OC-1 - OC-768

Short for Optical Carrier, used to specify the speed of networks conforming to the SONET standard.

SONET - Synchronous Optical Networking is a WAN transport protocol that supports transporting packets from different circuits over fiber optic cable.

SONET is a transport protocol for Asynchronous Transfer Mode (ATM) frames and is available at various bandwidths, which are denoted with an Optical Carrier (OC) level.

For example. OC-1 transmits it's payload at approximately 50 Mbps. Whereas OC-192

is at  10 Gbps Ethernet and transmits it payload at 9.6 Gbps.

SONET is designed for use 10 Gigabit Ethernet such as 10GBaseSW (40 kilometers), 10GBaseLW (25 kilometers) and 10GBaseZW (300 meters).  The 10GBase W specification designates use with SONET networks.

The following table shows the speeds for common OC levels.

OC =  Speed

OC-1 = 51.85  Mbps

OC-3 = 155.52 Mbps

OC-12 = 622.08 Mbps

OC-24 = 1.244  Gbps

OC-48 = 2.488 Gbps

OC-192 = 9.952 Gbps

OC-255 = 13.21 Gbps

OC-768 = 39.12 Gbps


The following is a diagram of a typical OC3 Network. The following is a fiber to fiber converter sometimes used with OC3 networks.