The ADSL WAN interface cards (WICs) on the Cisco 1700/2600/3700 series routers deliver business class ADSL over basic telephone service or otherwise known as Plain Old Telephone Service (POTS) (through WIC-1ADSL and WIC-1ADSL-DG) and ADSL over ISDN (through WIC-1ADSL-I-DG) services for small and medium-sized businesses to enterprise branch offices (Figure 1). These two ADSL WICs, combined with the Cisco 1700/2600/3700 Series routers, enable service providers and resellers to offer additional services by supporting features for business-class security, voice integration, differentiated classes of service, and managed network access with Cisco IOS Software. These value-added features, along with the manageability and reliability of Cisco IOS technology, provide the mission-critical networking that businesses require.