the project i am working on is of a web portal built on struts on websphere and with mainframes as the backend.As the volume of traffic is huge , in millions , there are many different types of mainframes working simulataneously.The app is using mercator/isec tool for the backend connection. I am fine with j2ee but the interface with mainframes is giving me headaches.I just dont the backend connection with them. Does someone has some experience with mercator.Any good book or any good tutorial would be really helpful. Internet and google are simply too confusing and complicated.