Multiple ASP Hosting

I would like to host two or more domains (each with its own IP address) running ASP on IIS 5.0, my concern is that, if one of the domains is having a bad coding problem or something similar to that like (DOS) , I don?t want the other domains to be effected how can this be implemented ? I need few details not only a short answer or at least an URL or article that shows that.

Thanks