The Telerik UI for ASP.NET AJAX suite provides only UI controls to be used withing ASP.NET WebForms pages.
There are not suitable controls that could ease you on achieving the desired functionality as this should be implement with native ASP.NET techniques.
Handling of the Session state, users and user groups is greatly dependent on the designed application and it cannot be handled by strict approach. This can be handled only per case and according to the specific application requirements.
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