Hope they prove to be useful to you.  | 
  
| 
    Digital Signal Level 
    Transmission Throughput US (ANSI)  | 
  ||
| Digital Signal Level | Throughput | Notes | 
| DS0 | 64 Kbps | 1 T1 Channel | 
| DS1 | 1.544 Mbps | 1 T1 (24 DSO's) | 
| DS1C | 3.152 Mbps | 2 T1's | 
| DS2 | 6.312 Mbps | 4 T1's | 
| DS3 | 44.736 Mbps | 28 T1's | 
| DS4 | 274.176 Mbps | 168 T1's | 
| 
     DS1's are commonly referred to as T's - T Spans - 
    T1's.  | 
  ||
 
| 
    Digital Signal Level 
    Transmission Throughput European (CCITT or ITU)  | 
  ||
| Digital Signal Level | Throughput | US Equiv. | 
| E1 | 2.048 Mbps | 1 T1 | 
| E2 | 8.448 Mbps | 4 T1's | 
| E3 | 34.368 Mbps | 16 T1's | 
| E4 | 139.264 Mbps | 64 T1's | 
| 
     It should be noted that the CCITT (Consultative Committee for International Telephony and Telegraphy) or the ITU (International Telecommunications Union) recognize DS0 through DS4 Signaling Levels.  | 
  ||