WAN Interface Card

A WAN interface card, or "WIC" is a type of specialized network interface card (NIC) made by Cisco that allows a network device such as a router to connect and transmit data over a Wide Area Network. A WIC has a built-in channel service data unit (CSU/DSU) interface to connect to a digital circuit and provide error correction and line monitoring.

A WIC is inserted into a WIC (or HWIC, or EHWIC) expansion slot in a Cisco device. According to Cisco, "Cisco interface cards are classified according to the technologies they support. For example, WAN interface cards (WICs) support WAN technologies, such as Gigabit Ethernet; and voice interface cards (VICs) support voice technologies. Voice/WAN interface cards (VWICs) can support voice, data, and voice and data applications, depending on the capabilities of the router in which the VWIC is installed." The WIC is supported by many Cisco devices, particularly their branch routers including the 2500 series routers and it's successors.