The 1.3a version of the ACE ORB (TAO), pronounced "dow", is a CORBA V2.6 compliant, C++, object request broker. It is a second generation ORB developed with a highly extensible architecture as a result of its use of what might be termed a pattern framework, more commonly known as the ACE library. (ACE is an acronym for ADAPTIVE Communication Environment, ADAPTIVE is another acronym and stands for A Dynamically Assembled Protocol, Transformation And Validation Environment!).

Although designed to meet the demanding requirements of hard real time systems, TAO can be easily used "out of the box" for general purpose CORBA middleware applications. Its design to meet exacting real time needs, which can be described as Quality of Service (QoS) requirements, has resulted in superior predictability, complete end to end determinism, high performance, and a scaleable implementation.

TAO supports IIOP 1.2 enabling a high degree of interoperability with other conforming ORBs. By means of TAO's support for pluggable protocols new transport technologies can be introduced without disruption to higher level code and systems. Networking technology migrations are made easier.