An unmanaged switch is a basic Ethernet switch with no configuration interface. It forwards traffic automatically based on MAC addresses, requires no setup, and has no management features beyond status LEDs. Plug devices in and the switch handles the rest.

In short: Unmanaged switches are appropriate for small networks where every connected device is equally trusted, where there is no need to segment traffic, and where the cost and complexity of a managed switch is not justified. A small office, a single-purpose plant cabinet, or a domestic deployment is often well served by an unmanaged switch. Industrial unmanaged switches (with DIN rail mounts, wide temperature operation, and DC power inputs) are widely used in plant cabinets where the network behind them is already segmented by the upstream router or managed switch.

For IoT and OT deployments, unmanaged switches have a place but are rarely the right choice for the primary site network. The lack of VLAN support means every connected device shares one broadcast domain. The lack of port authentication means anyone with physical access to a port can join the network. The lack of monitoring means problems are invisible until they affect users. These trade-offs are acceptable in some constrained applications (a small group of cameras feeding into a single NVR, for example) but problematic for general-purpose IoT estates.

Teltonika TSW101 and similar entry-level industrial switches occupy the boundary between managed and unmanaged: they offer some configuration but at a lower price point than full managed switches. For most IoT deployments needing more than four ports, the recommendation is to specify a fully managed switch rather than an unmanaged one, because the marginal cost is usually small and the operational flexibility is significantly greater.