Spotfire's intelligent scheduling and routing server topology is (as far as I am aware) unique in the industry. It works with Web Player and makes the best use of the available server resources. Since it's specifically designed for Spotfire, it has context-aware load management. It knows which analysis a user is requesting and so it can route the user to the most appropriate Web Player instance. The most appropriate instance is determined by a set of rules that the server administrator defines.
Spotfire also shares memory and data between multiple users (if the analysis they are working with resides on the same Web Player instance), so it makes sense to share as much as possible and minimize the number of instances that have an analysis file loaded. Traditional load-balancing algorithms usually direct users to...