Ethernet cabling is used to hard-wire local area networks (LANs), and gigabit Ethernet (GbE) is a set of Ethernet standards with a minimum data transfer speed of 1-gigabit per second (gbps). This is equivalent to 1,000 megabits per second (mbps), thereby surpassing previous FastEthernet and original Ethernet speeds of 100 mbps and 10 mbps respectfully. The Institute of Electrical and Electronics Engineers (IEEE) sets the standards for Ethernet technologies. This allows manufacturers to make networking hardware and software that is compliant with uniform "flavors" of Ethernet. There are four such flavors of GbE.
As outlined in IEEE’s 802.3z and 802.3ab standards, GbE uses one of two types of optical fiber, twisted pair, or copper cabling, though the latter is legacy technology. Of the optical cabling used, there is multi-mode and single-mode cable. The difference lies in how signals are transmitted through the lines.
Each GbE standard is designated by an abbreviated name. The “1000” refers to the speed of 1,000 mbps. “Base” is short for baseband, and the two initials at the end point to the type of cabling technology used. The abbreviations are as follows:
- 1000Base-LX – GbE using longwave laser over dual multi or single-mode optical fiber cables
- 1000Base-SX – GbE using shortwave laser over dual multi or single mode optical fiber cables
- 1000Base-TX – GbE using four pairs of unshielded twist pair cables rated Category 5
- 1000Base-CX – GbE using two pairs of shielded twisted pair cables
Category 5 cable, sometimes called Cat-5, is labeled as such by the manufacturer. There are various categories of cables based on their technical specifications. Sometimes, the designation of 1000Base-X is used as a generic inclusive reference to GbE without specification as to type or cabling.
GbE cabling is effective over defined distances, so the length of cable required for a particular LAN might necessitate a specific flavor of GbE. Some laptops and motherboards are already incorporating GbE for built-in capability. GbE has already been surpassed by 10-Gigabit Ethernet (10GbE). This flavor of Ethernet is 10x faster than 1-GbE, and is sometimes referred to as XGbE.