The ComNet CNGE20MS is a 20-port Managed Ethernet Switch designed to reliably operate in harsh, environmentally challenging applications. It features eight 10/100/1000BASE-TX and twelve 100/1000BASE-FX SFP (Small Form-Factor Pluggable Module, sold separately) ports. The SFP ports are 100/1000Mbps configurable for either multimode or single-mode optical fiber by the use of optional ComNet SFPs. Exclusive to ComNet is C-Ring, a feature that protects the network from interruptions or temporary malfunctions with fast recovery technology. Legacy ring allows the switch to be used in an existing ring of ComNet X-Ring enabled switches. Redundant DC inputs are included for uninterrupted operation in the event of a power supply failure. These network-managed layer 2 switches are optically and electrically compatible with any IEEE802.3 compliant Ethernet device.