Multiservice Interchange (MIX) module adds time-division multiplexing (TDM) connection capabilities to all Cisco 2600 and 3600 platforms. MIX enables the combination of different types of traffic on a single T1 or E1 connection, allowing smooth migration from TDM voice to packet voice on one integrated platform. Customers can also save WAN bandwidth by mixing TDM voice and packet data on the same link using the Drop & Insert function (Integrated Add/Drop Multiplexing).