How many ds1 in a OC1?

An OC-1 (Optical Carrier Level 1) can carry 51.84 Mbps of data, which is equivalent to 672 DS-1 (Digital Signal Level 1) circuits. Each DS-1 circuit has a data rate of 1.544 Mbps. Therefore, there are 672 DS-1 channels in one OC-1.