Enhancing the User Interface of the CMS Level 1 Trigger Online Software with AJAX

This paper presents a server-side C++ library (AjaXell) for developing a graphical user interfaces in Common Gateway Interface compliant servers. AjaXell is based on the Asynchronous JavasScript and XML technology and has been tested in the Apache Tomcat and the Cross Platform Data Acquisition servers. AjaXell has been envisioned to enhance the browsable user interface of the trigger supervisor system, developed within the Compact Muon Solenoid experiment. A number of feasible technological options to implement the library are discussed. The trigger supervisor graphical user interface is presented as an application example. This demonstrates how a web-based desktop-like user interface can be implemented with AjaXell and how this eases the set-up, test, operation and monitoring of the Level 1 Trigger of the CMS experiment.