(Digital Signal) A classification of digital circuits. The DS technically refers to the rate and format of the signal, while the T designation refers to the equipment providing the signals. In practice, "DS" and "T" are used synonymously; for example, DS1 and T1, DS3 and T3. See OC.
NORTH AMERICA, JAPAN, KOREA, ETC.
Voice
Service Channels Speed
DS0 1 64 Kbps
DS1 24 1.544 Mbps (T1)
DS1C 48 3.152 Mbps (T1C)
DS2 96 6.312 Mbps (T2)
DS3 672 44.736 Mbps (T3)
DS4 4032 274.176 Mbps (T4)
EUROPE (ITU)
Voice
Service Channels Speed (Mbps)
E1 30 2.048
E2 120 8.448
E3 480 34.368
E4 1920 139.264
E5 7680 565.148
SONET CIRCUITS
Service Speed (Mbps)
STS-1 OC1 51.84 (28 DS1s or 1 DS3)
STS-3 OC3 155.52 (3 STS-1s)
STS-3c OC3c 155.52 (concatenated)
STS-12 OC12 622.08 (12 STS-1s, 4 STS-3s)
STS-12c OC12c 622.08 (12 STS-1s, 4 STS-3c's)
STS-48 OC48 2488.32 (48 STS-1s, 16 STS-3s)
