The document discusses Cisco's ASR 9000 router system architecture. It provides an overview of the ASR 9000 product portfolio including the ASR 9901, ASR 9904, ASR 9906, and ASR 9910 models. It describes the key components and features of the routers, such as their networking processors, line cards, switching fabric, and packet processing capabilities. The document also reviews the evolution of the ASR 9000 line cards from earlier generations to the current Tomahawk-based cards.