A chip that performs encoding and decoding to facilitate the transmission of  voice data with high efficiency and speed across the network. Microsoft uses WAV files which are ususally uncompressed. In VoIP, the most frequently used compression algorithms are G.711 (uncompressed, at 64 KBs) , G.723 (24 and 40 KBs) , G.726 (16, 24, 32, and 40 kbit/s) , and G.729 (8  KBs).