Transceivers are is a type of removable component that integrates the transmit and receive functions needed to convert between serial-electrical and serial-optical signals, simplifying switch and hub design for high-speed networking.

The GBIC (Gigabit Interface Converter) specification defines a common form factor and electrical interface. This pluggable transceiver module enables networks to be incrementally expanded and reconfigured, as required. Initially targeted to support Fibre Channel data networks, the GBIC standard has also been adapted for use with Gigabit Ethernet installations.

A related item is the SFP (Small Form Factor Pluggable). This is a smaller form factor transceiver that replaces the GBIC. Some literature treats the SFP as a type of GBIC (a mini-GBIC).

Now that transciever speeds typically exceed 1 Gigabit, the term GBIC is a bit of a misnomer though ofter used interchangably with transcievers of much higher speed.