A Offers wide variety of LAN and WAN options; network interfaces are field-upgradable to accommodate future technologiesA Provides many types of slots to add connectivity and services in the future on an ''integrate-as-you-grow'' basisA Supports more than 30 modules and interface cards, including existing WAN (WIC) and multiflex (VWIC) interface cards ( for data support only on the Cisco 1841 router) and advanced integration modules (AIMs)