SLAC, Menlo Park, California
ORNL, Oak Ridge, Tennessee
Channel Access Markup Language (CAML) is an XML based markup language and implementation for displaying EPICS channel access controls within a web browser. The CAML II project expanded upon the work of CAML I allowing for more power and greater integration with other web technologies. The most dramatic new feature introduced in CAML II is a namespace in support of XHTML so CAML controls can be embedded within HTML documents. A repetition template with macro substitution allows for rapid coding of arbitrary XHTML repetitions. Enhancements have been made to several controls including more powerful plotting options. Advanced formatting options were introduced for text read back controls. Virtual process variables allow for custom calculations. An EDL to CAML translator eases the transition from EDM pages to CAML pages.
BNL, Upton, Long Island, New York
As part of the IRMIS3 development we started to take advantage of Web technologies and implemented a REST service to capture the business logic and access to IRMIS data. We will review the design and the implementation of the server side, motivating the decisions and describing the use of the different technologies. We will discuss what we found to work, what we had to work around and how designing services first allows easier integration and evolution on the client side.
CERN, Geneva
DIP is a middleware infrastructure developed at CERN to allow lightweight communications between the various distributed components of a control system (such as detector control systems or gas control systems). DIP publications are currently subject to a lack of visibility from the CERN general purpose network and a lack of formal service level agreements between information publishers and consumers. The DIP contract management system adresses these limitations by providing a publication monitoring tool that can make available both publication data and publication status on the web through a javascript API for inclusion in web pages and integration with advanced AJAX libraries (such as the Google Web Toolkit Visualization API). It also performs status information logging, and advertises such information in the form of DIP publications (to ease integration with SCADA systems such as PVSS). We will demonstrate how complex structured information can be easily made available to a large array of consumers through the usage of the Spring framework and the multiple configuration based adapters it offers to a vast choice of communication protocols.
DESY, Hamburg
ANSTO, Menai, New South Wales
Tech-X, Boulder, Colorado
As accelerators become bigger, traditional ways of building the control systems based on a single framework no longer scale. A Service-Oriented Architecture (SOA) adopting both RPC and a MOM standard service buses promotes multiple levels of loose coupling to increase the robustness and adaptability of overall control applications without sacrificing performance. The emerging OMG DDS specification defines a data-centric communication standard with rich supports for quality-of-service. It is especially suited as the SOA's MOM service bus for control systems. DDS helps extend the real-time data available from the proven control development framework such as EPICS, as standard services and data exchanges between services in a SOA environment. In this paper, we review various features in the OMG DDS standards and their applications in control applications. We also illustrate how, collaborating with Web Services, DDS fits into a SOA for accelerator control systems. Finally, we present and evaluate performance benchmarking results of several DDS implementations, including an EPICS-DDS, which is an open source implementation of OMG DDS.