Tellabs, Inc. designs, develops, and supports telecommunication networking products for communication service providers in the United States and internationally. The company operates through four segments: Optical, Data, Access, and Services. The Optical segment offers digital cross-connect systems, managed transport systems, optical transport systems, and Metro Ethernet Switching products that enable service providers to manage network bandwidth by adding capacity; and to support metro networks, mobile services, and business services for enterprises, as well as to provide triple-play voice, video, and data services for residential consumers. The Data segment provides next-generation packet-switched products that enable wireless and wireline carriers to deliver mobile voice and Internet services, and wireline business services to their customers, as well as offers managed access system and smart routers. The Access segment provides multiservice access series and optical network terminal series products that enable service providers to deliver bundled voice, video, and high-speed Internet/data services, as well as enable optical local area networking using gigabit passive optical network technology. The Services segment delivers deployment services, including project management, engineering, material furnishing, installation, testing, and acceptance; training services; support services; and professional services comprising consulting and network design services. It serves wireline and wireless service providers, multiple system operators, and competitive service providers, as well as distributors, original equipment manufacturers, system integrators, and government agencies. Tellabs, Inc. was founded in 1974 and is headquartered in Naperville, Illinois.

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