The Conexant D480 MDC V92 Modem is a dial-up modem that was commonly used in older computers for analog voice and data communication over telephone lines. The V92 refers to a version of the V.92 standard, which is a protocol for faster dial-up internet connections (with features like quicker modem handshakes and the ability to resume interrupted connections). The MDC (Modem Data Communication) part refers to the communication chipset used in the modem.