The dual-serial port WAN Interface Card (WIC-2A/S) provides higher levels of serial port density for a single WIC and is supported on the Cisco 1700, 2600, and 3600 series. The low serial speed WIC-2A/S supports up to 128 Kbps synchronous or 115.2 Kbps asynchronous serial links. Each port on a WIC is a different physical interface and can support different protocols such as Point-to-Point Protocol (PPP) or Frame Relay and Data Terminal Equipment/Data Communications Equipment (DTE/DCE). This WIC supports mixed asynchronous and synchronous operation on a single card as well.

These dual-serial port WICs feature Cisco's new, compact, Smart Serial connectors to support a wide variety of electrical interfaces when used with the appropriate transition cable. This includes: V.35, RS-232, RS-449, RS-530, RS-530A in male and female versions for both DTE and DCE devices. This feature provides easy configuration and reconfiguration as network requirements change, without the need of purchasing a different serial interface card.