Source : Free On-Line Dictionary of Computing

E1
     
         A European {framing specification} for the
        transmission of 32 {DS0} (64 kb/s) data streams.  By
        extension, it can also denote the transmission rate required
        (2.048 Mb/s = 2048 kb/s).  Unlike {DS1} it is free of
        {bit-robbing}.
     
        (2002-03-22)