10 Sep 2018 If so, your internet service provider might be slowing down your data on purpose. New net neutrality rules, born in 2015 and struck down two years later, were For example, if high-resolution video is a priority, research the Here is a list of large ISPs in the U.S. These providers offer Internet service through DSL, copper, fixed wireless, cable Internet, fiber-optic services, and mobile broadband. Top ISPs. Comcast Xfinity. Comcast Xfinity offers cable Internet service across 40 states to approximately 110 million people. Internet service provider (ISP), company that provides Internet connections and services to individuals and organizations. In addition to providing access to the Internet, ISPs may also provide software packages (such as browsers), e-mail accounts, and a personal Web site or home page.