Basically, an unmanaged switch is a device that forwards packets within a LAN. It is a truly plug and play device which does not require any configuration. Just plug in it, connect the Ethernet cables from users such as personal computers or I/O devices, and it will immediately communicate data between users.
The Ring switch has extended capabilities. It allow to connect devices in a Ring topology. When a link is broken, the Ring switch instantly transfers data to new path. This provide fast network and avoid fault on the network.
A managed switch is a device that forwards packets between LANs. This device also has to capability to support loop configurations using Spanning Tree Protocol. Loop configurations are used to prevent a single point of hardware failure in a network. Management Information about the network is also obtained through the switch by querying the MIB can be configured to improve the network performance and control the traffic. They may be configured via a Telnet console or even a web browser. Different management features are available.