The pool model
Like the default destination configuration model, the pool destination configuration model has a one-to-many relationship between a logical destination and two or more actual destinations.
This model is very effective when you have output devices that you want to group together based on factors such as location, capability, speed, and capacity. You might also want to group them based on who uses them or who manages the output they generate. For example, access to a specific group of printers can be restricted to members of the billing department. Moreover, different types of statement jobs might use different sets of job- and document-attribute defaults, such as the form they print on or the overlay they require. The pool model allows these different jobs to be submitted to a single logical destination. It then automatically routes each job to the first available printer capable of processing it. In this way, the pool model helps with workload balancing.