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).
This is the feature, which allows two or more locations to interact between each other by using synchronized audio and video delivering a video conference call. Software applications such as Skype or Google Talk offer a free way of video conferencing.