Monitoring is a surveillance function that is used equally for network monitoring, but also in many other IT applications. Indata centers and smart grids, in web stores and fleet management, and in many other monitoring activities.
More generally, monitororng can be performed in different phases of operation. When it is performed in advance of events, it is called predictive monitoring, which acts in a forward-looking manner. Proactive monitoring detects potential problems and can react to them predictively. The situation is different with real-time monitoring, where monitoring is performed in real time, allowing administrators to respond immediately to current events and changes. If monitoring is carried out after the detection of deviations and changes, this is referred to as reactive monitoring.
If we consider the monitoring of networks, then this refers to the monitoring of performance-relevant network parameters. These are: Delay times, response time behavior, data throughput, packet loss, load distribution and various others. If corresponding deviations are detected, then better connections with shorter runtimes or other routes are selected via the network management.
Reactive monitoring is supported by powerful software tools and displayed on monitoring devices in the form of tables, line charts and histograms. The various functions of the monitoring tools can be assigned to the layers of the OSI reference model. This means that corresponding tools monitor the functions of the transmission media, others those of the network cards, and still others functionally monitor the transport and application-oriented layers and thus software services located on the server. Such monitoring cannot prevent bottlenecks, nor can it rule out failures or malfunctions.
An example of such a tool can be found under Windows in the Control Panel under Administration Services. Other centrally operating monitoring tools use agents and the Simple Network Management Protocol( SNMP) or Windows Management Instrumentation(WMI).