Most network engineers are very familiar with tools that report statistics on individual components such as links, routers, and servers; these infrastructure monitors have been around for a long time.

Newer to the market are performance monitoring appliances that report end-to-end statistics and the end-user experience; these appliances provide a unique and comprehensive view of the enterprise without the need for desktop or server agents. They not only measure how well response time Service Level Agreements (SLAs) are being met, they also help solve a wide variety of problems with solutions that lead to significant reductions in operating costs.

End-to-end performance monitoring can be extremely useful as a proactive method for both rapid troubleshooting and performance management of enterprise networks and server aggregations. It has been successfully implemented to quickly identify and resolve the myriad of performance issues associated with networks, servers, and applications.

The use of end-to-end performance monitoring appliances has uncovered serious inefficiencies with load balancers, poorly designed applications, bypassed proxy servers, ineffective cache servers, aggressive active agents, and badly designed "redundant" networks.They can provide the "big-picture" view of networks and applications, answering questions that are critical for the enduser experience