Trading turrets, unlike typical phone systems, have a number of features, functions and capabilities specifically designed for the needs of financial traders.
In addition, many traders have dozens or hundreds of dedicated speed dial buttons and large distribution hoot-n-holler or Squawk box circuits which allow immediate mass dissemination or exchange of information to other traders within their organization or to customers and counter-parties.
Due to these requirements many Turrets have multiple handsets and multi-channel speaker units, generally these are shared by teams (for example: equities, fixed income, foreign exchange) or in some cases globally across whole trading organizations.
Unlike standard Private Branch Exchange telephone systems (PBX) designed for general office users, Trading turret system architecture has historically relied on highly distributed switching architectures that enable parallel processing of calls and ensure a "non-blocking, non-contended" state where there is always a greater number of trunks (paths in/out of the system) than users as well as fault tolerance which ensures that any one component failure can not affect all users or lines.
As processing power has increased and switching technologies have matured, voice trading systems are evolving from digital time-division multiplexing (TDM) system architectures to Internet Protocol (IP) server-based architectures.