E1 = 32 – 64 kbps Channels

30 of the 32 channels are able to carry digitally encoded voice band telephone signals or data (2 perform communications overhead tasks)

All 32 channels combined form a DS1 with a 2.048 Mbps Transmission Rate

E2 = 4 – E1 Channels 8.448 Mbps

E3 = 4 – E2 Channels 34.368 Mbps

Used in most countries except the United States and Japan

Developed by CEPT

E1 – E3 Carrier System