The company I work for runs a web site that gets a little over fifty million hits a month. We are looking at replacing our existing custom-written ad server with a prepackaged solution. It fundamentally must be able to scale up to this level of traffic, which eliminates a substantial number of solutions.
Our servers run Linux and so any ad server would obviously need to run in Linux.
Anyone have any software and (less important) hardware recommendations for ad serving that can easily handle 50,000,000 hits per month, and that can scale up modestly into the low nine figure hits/month? Happy to hear about Windows solutions, though we definitely will not be running those.