Web Service Atomic Transaction is an OASIS standard. To achieve all-or-nothing property for a group of services, it defines three protocols and a set of services. These protocols and services together ensure automatic activation, registration, propagation and atomic termination of Web Services. WS-AT is more applicable in business needs for trustworthy. The Byzantine Fault Tolerance (BFT) techniques are suitable to protect the core services in WS-AT. The objective of Byzantine fault tolerance is to be able to defend against Byzantine failures, in which components of a system fail in arbitrary ways ( not just by stopping or crashing but by processing requests incorrectly, corrupting their local state, and/or producing incorrect or inconsistent outputs). The main thing of WS-AT services used to minimize the use of Byzantine Agreement (BA) in BFT technique.