Are T1 lines obsolete? Are copper phone lines being phased out? Yes. As technology evolves, telecom services can become outdated and no longer provide the necessary functionality they once could. A T1 line is an old telecom technology that provides 1.5M of bandwidth between two sites. While these lines served many purposes such as internet connections, phone calls, and point-to-point data, people have outgrown T1 lines and are searching for a more cost-effective telecom solution.