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 blacklist represents itself a list or register of entities which are denied privileges, service, mobility, access and admission due to these or other reasons. This function blocks all connections from the subscribers who are in the list.