A European format for digital transmission. E1 supports signals at 2 Mbps (32 channels at 64Kbps, with 2 channels reserved for signaling and controlling), versus the T1, which carries signals at 1.544 Mbps (24 channels at 64Kbps).
The common name shared by communication protocols, technologies and
methods ensuring the transfer of the voice signal via the Internet network or
by any other IP-networks. The signal is transferred by the communication
channel in the digital form and, as a rule, before transferring compresses in
order to remove abundance.