What is a 'Managed' Switch?
This is the number 1 FAQ in the area of industrial networking.
While an 'unmanaged' switch provides no means of user configuration, a 'managed' switch provides a number of configurable parameters. These settings allow the network's behaviour to be managed, and may include provision for redundancy, network segregation, priortisation, network management or alarming. The Hirschmann SPIDERs shown here (left) are examples of unmanaged switches. These are typically located in field cabinets as end points in networks, where there is the requirement to add devices to a network simply, and perhaps provide a local access point to the network. Despite being considered 'entry-level' devices, even unmanaged switches feature auto-crossing, auto-negotiation and auto-polarity to simplify installation and choice of cable. Being industrial products, they are designed for DIN rail mounting, with 24Vdc power supply.
Managed switches typically include functions such as:
- IGMP Query / Snooping
- Quality of Service - enables prioritisation for different classes of traffic
- Power over Ethernet (PoE)
- Advanced Diagnostic functions such as traps, port mirroring, duplicate addresses detection and and even cable testing.