Take advantage of DotNetNuke's security contexts using normal .asmx files for Web Services. IWebLite contains a single class -- SecurityContext.cs -- which you can leverage to figure out which user is logged in and whether they have access to the module in question. There's no need to use a large and cumbersome framework like IWeb. IWebLite allows you to use multiple .asmx files, and allows you to authenticate using normal DNN Module permissions. IWebLite has been tested with DNN authentication and Windows Live Authentication.
IWebLite is not a version of, nor uses any code from, the IWeb Project. In many cases it's an excellent replacement for IWeb.