SONET - is a standard for optical telecommunications transport. It was formulated by the ECSA for ANSI (T1.119), which sets industry standards in the United States for telecommunications and other industries. The comprehensive SONET/synchronous digital hierarchy (SDH) standard is expected to provide the transport infrastructure for worldwide telecommunications for at least the next two or three decades.

Signal	Bit Rate (Mbps)	Capacity
STS–1, OC–1	51.840	28 DS–1s or 1 DS–3
STS–3, OC–3	155.520	84 DS–1s or 3 DS–3s
STS–12, OC–12	622.080	336 DS–1s or 12 DS–3s
STS–48, OC–48	2,488.320	1,344 DS–1s or 48 DS–3s
STS–192, OC–192	9,953.280	5,376 DS–1s or 192 DS–3s
Note: STS = synchronous transport signal OC = optical carrier