T1 lines are the standard Internet connections for tens of thousands of companies and offices. Typically, T1 lines are used by small to medium sized offices to provide high-speed Internet connectivity to all employees, through the use of a LAN or WAN.

T1 Lines are provided by telecom companies at a monthly service fee, and are able to deliver 1.544 megabits per second, or the equivalent of 192,000 bytes per second. T1 lines are approximately 60 times faster than a standard dial-up connection, and are much more reliable than other connection types such as cabl e or D SL. As a result are almost a necessity for any office sized more than a few people. Companies larger than 15 people may need ever larger connections (such as T3 or OC3) in order to provide a high quality connection.