Located in West Allis, Wis., AT&T is one of the leading worldwide providers of telecommunication services. It offers Internet protocol based communications services to businesses. The company offers a range of services, such as consumer services and small business services. It has one of the fastest mobile broadband networks and one of the largest international coverage of any United States wireless carrier. AT&T provides wireless data coverage with wireless data-roaming in more than 200 countries. Additionally, it offers laptops, hand-held devices, data services and mobile broadband services.