Abstract: A method and system for controlling and guaranteeing a service level agreement (SLA) based on a communications outbound link bandwidth usage to a plurality of customers having electronic business activity hosted by at least one server as a server farm, includes monitoring the outbound communications bandwidth usage by each customer traffic to determine a level of service being provided to each customer with respect to the agreed service level agreement in each service cycle time per unit of time. The flow of incoming requests to each customer business activity application is controlled so as to guarantee a level of service previously agreed to the customer by queuing requests to the customer and by selectively dropping requests to the customer to guarantee the agreed service levels to the customer. The controlling process controls and guarantees each outbound link usage based service level agreement by controlling the flow of incoming requests to the at least one server.