. In combination with the Cisco 1921 and 1941 Integrated Services Routers (ISRs) and Cisco 2900, 3900, and 3900E Series ISRs, this EHWIC provides high-speed digital data transmission between customer premises equipment (CPE) and the central office (DSL access multiplexer [DSLAM]), usually located on the telephone company premises. This capability enables service providers and resellers to offer additional services such as business-class security; voice, video, and data; differentiated classes of service (QoSs); and managed network access with Cisco IOS? Software over existing telephony infrastructure. These value-added features, along with the flexible manageability and reliability of Cisco IOS Software, provide the mission-critical networking features that businesses expect.