T lines - Single Signal 64Kbps - Single DS0 Channel
T1/ E1 and T3/ E3 utilizes multiple 64Kbps channel to provide high speed internet
Commonly referred as “dedicated” leased lines. They are leased from telecommunication company to provide dedicated circuit switched network

TypeSpeedDetails
DS064KbpsSingle Channel
T1 (DS1)1.544Mbps24 DS0 64Kbps Channels
E1 (DS1)2.048Mbps30 DS0 64Kbps Channels
E3 (DS3)34.368Mbps512 64Kbps Channels
T3 (DS3)44.736Mbps672 64Kbps Channels

Bandwidth Chart - Termnologies