ASP.NET session management through web.config file in C#
Setting the sessionstate is one of the methods in ASP.NET to manage the session. 

<sessionState 
    mode="InProc"
    stateConnectionString="tcpip=127.0.0.1:42424"
    sqlConnectionString="data source=127.0.0.1;Trusted_Connection=yes"
    cookieless="false" 
    timeout="20" />