Keeping an IP address in Windows Azure

During one of my Azure presentation I was asked whether we could fix the ip address of an azure role so that we can use the ip address to access some external service that uses the ip address to verify the calling party. I didn’t think that there was a way to do this but after talking with Simon Davies at Microsoft he pointed me to a blog post he made on this topic.

How does IP address allocation work for Compute Services in Windows Azure? – Simon Davies