Going With the Netflow for Network Management. By Drew Robb

For over 15 years, network monitoring for most companies meant using a utility which pings all of the critical devices on the network.  If the device doesn’t respond, a notification is sent out.  Since the early ’90s these utilities have become increasingly sophisticated, using synthetic transactions to ensure the actual application is running. Response time and availability reports can also be generated from the polled data and most network monitoring applications are even providing SNMP trends.

http://www.enterprisenetworkingplanet.com/_featured/article.php/3797511/Going-With-the-Netflow-for-Network-Management.htm