According to whether the switch supports network management function, we can divide the switch into "network management type" and "non-network management type".
The task of network management switch is to keep all network resources in good condition. Network management switch products provide a variety of network management methods, such as Console-based, Web-based and Telnet-based remote login network. Therefore, network managers can monitor the switch's working status and network running status locally or remotely in real time, and manage the working status and mode of all switching ports globally. Network management switch supports SNMP protocol. SNMP protocol is composed of a set of simple network communication specifications. It can accomplish all basic network management tasks. It needs less network resources and has some security mechanisms. The working mechanism of SNMP protocol is very simple, mainly through various types of messages, namely PDU (Protocol Data Unit) to achieve the exchange of network information. But network management switches are much more expensive than the non-network management switches described below.
Network management switch uses embedded remote monitoring (RMON) standard to track traffic and conversations, which is very effective for determining bottlenecks and blocking points in the network. Software agents support four RMON groups (history, statistics, alerts and events) to enhance traffic management, monitoring and analysis. Statistics are general network traffic statistics; history is network traffic statistics within a certain time interval; alarms can be alarmed when the preset network parameters limit is exceeded; time represents management events.
There are also network management switches that provide policy-based quality of service. Policies refer to the rules that control the behavior of switches. Network administrators use policies to allocate bandwidth, priority and control network access for application flows. The emphasis is on the bandwidth management strategies needed to meet service level protocols and the way to publish policies to switches. A comprehensive and convenient visual management system is formed by the multi-functional light emitting diode (LED) used to represent port status, half-duplex/full-duplex and 10BaseT/100BaseT at each port of the switch, as well as the switching stage LED used to represent system, redundant power supply (RPS) and bandwidth utilization. At present, most of the switches below the departmental level are non-network management type, only the enterprise level and a few departmental level switches support network management functions.