title: Gradually migrating Classic ASP 3.0 to ASP.NET MVC
body: <p>I'm evaluating a migration from a classic ASP 3.0 application to ASP.NET MVC. I've already migrated applications to WebForms, but have decided to try MVC for this migration for a number of reasons, including the fact the code in this application is NOT spaghetti and seems to lend itself to an MVC style layout.</p>
  
  <p>One major constraint on this migration is that it has to be gradual with minimal (or preferably no) downtime, and it should be possible to continue development while the migration is in progress. This means that the classic ASP code has to run side-by-side with the ASP.NET MVC code, probably even in the same IIS application.</p>
  
  <p>So, I have a couple of related questions:</p>
  
  <ol>
  <li>What's the best way to prevent rerouting from affecting classic .asp files? (Ignore them, HttpHandler, special reroute rules?)</li>
  <li>Are there any special non-obvious issues that people have encountered in similar scenarios/migrations?</li>
  <li>Are the authentication, session and general code re-use issues that generally crop up in regular ASP to WebForms migrations any different when working with ASP.NET MVC?</li>
  </ol>
  
  <p>Thanks in advance!</p>