Network Performance Management builds on Network Management practices and is focused on maximizing the throughput and performance of computer networks. This is accomplished with tools that continuously monitor traffic across the network, and the response from applications and services on the network. Self-healing of the network is a common function deployed to allow contested network paths to be routed around, and for overloaded servers to not receive new requests. Load balancers are used to route requests to the applications and services best placed to handle them at any point in time. Routing is done at the network and application layer to allow decisions to be made at an appropriate level.