The OPC Web Alarm.NET control is .NET component that can be integrated into any ASP.NET web application. The component is 100% managed code and works with any local and/or remote OPC Systems Service.
No license is needed to use the components. It can connect to any OPC Systems Service that has an OPC Web Alarm.NET license.
Refer to OPC Web Alarm.NET properties section in this help file for more details on the OPC Web Alarm component.
For quick introduction to the OPC Web Alarm control view the following video.
Detailed step by step instructions on implementing alarm window in web application.