optical carrier (OC-x) levels

Definition of optical carrier (OC-x) levels in The Network Encyclopedia.

What is optical carrier (OC-x) levels?

A set of signaling rates designed for transmission over Synchronous Optical Network (SONET) networks. Optical carrier (OC-x) levels also apply to Asynchronous Transfer Mode (ATM) networks. The term “optical carrier” indicates that SONET runs over fiber-optic cabling. The following table shows some of the common OC-x transmission rates.

OC-x Transmission Rates

Name Rate
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
NOTE

OC-1 is roughly equivalent to T3 in the T-carrier system. It is a standard SONET Synchronous Transport Signal (STS) transmission rate of 51.85 Mbps. This data transmission rate is known as STS-1. Higher data transmission rates (OC-3, OC-12, and so on) are multiplexed STS-1 transmissions. In other words, OC-3 is three times faster than OC-1 (STS-1).