I developed a intranet applications with Rails (3.2) for one of my customers. There will be around 30-40 employees working with it. Backend is MySQL (5).

What would be the best way to determine the servers specs needed?

Given:

• max. load will be roughly 2400 (40*60) HTTP requests (mixed GET / POST) per hour.
• 15% of these calls are JSON calls (iOS)
• avg request will make between 5-10 database calls
• 500-800 SQL INSERTS per day
• webpages are fairly simple (no images, just text)
• avg webpage is 15 request (css/js/etc) and total size is 35-45 KB

More specific, since they need access from multiple geographical locations, we are thinking of running a bitnami Ruby stack in the AWS cloud (uptime is important). Any thoughts on a AWS Instance (small/medium) and Utilization (light/medium/heavy) ?

Thanks!