Designed for use with the EtherSwitch 1420 Ethernet switch, the EtherSwitch 1420 modules consist of three Fiber Distributed Data Interface (FDDI) modules that support both fiber-optic and Category 5 unshielded twisted pair (UTP) cabling and four 100BaseT modules that support the 100BaseTX and 100BaseFX physical media specifications.Without interrupting the network, these hot-swappable modules plug directly into the EtherSwitch 1420 high-speed expansion slots. The EtherSwitch 1420 then automatically configures the module to the network and verifies its operation.