Session sharing between Classic ASP and ASP.NET

Recently for a project which was a mix of classic ASP and ASP.NET, I was exploring ways of sharing session between classic ASP and ASP.NET.

After a bit of research, I found following three ways -

Option 1 –

• Use nSession DLL - http://nsession.codeplex.com/
• This provides a library which can be used in both ASP.NET and classic ASP applications to access session values. 

Option 2 –

• Store session in SQL Server by encrypting it from ASP.Net page
• Retrieve session from SQL server by decrypting it in ASP page
• Standard Microsoft approach - https://msdn.microsoft.com/en-us/library/aa479313.aspx

Option 3 –

• From ASP.NET page, encrypt session and pass in query string or store in a cookie.
• Redirect to classic ASP page.
• Get the encrypted value from query string or cookie, decrypt it and store in classic ASP session.
• This new session can be used in application.

We have followed 'Option-2' which is standard recommended approach by Microsoft and is also a safer option with respect to security.