Optics Telecom

Gigabit Ethernet is a term describing various technologies for transmitting Ethernet frames at a rate of a gigabit per second, as defined by the IEEE 802.3-2008 standard. 1000BASE-X is one physical layer standard for Gigabit Ethernet utilizing optical fiber. Using fiber interfaces on your network hardware is a choice that requires some thought based on your unique requirements. This post provides you with some basic information that you should understand before you decide which type you will choose for your 1000BASE-X Gigabit network connection.

1000BASE-X is a group of standards for Ethernet physical layer standards, specified within the IEEE 802.3.z standard. It is used for gigabit Ethernet connections that transmit data mainly over fiber optic cable, and sometimes over copper-shielded cable. The standards that apply to the term 1000BASE-X include 1000BASE-LX, 1000BASE-SX, 1000BASE-BX10, 1000BASE-LX10, as well as non-standard -ZX and -EX standards. The range of lengths for 1000BASE-X starts at a minimum of 25 meters for copper wires and a maximum of 70 km in the case of a single-mode optic fiber channel. All of the standards that are grouped at 1000BASE-X utilize a 8b/10b encoding where 8 bits are reserved for data transmission while 2 bits are used for error correction. The following are brief explanations of some of the standards grouped under the 1000BASE-X standard.

1000BASE-SX Gigabit Ethernet is a variant coupled to a VCSEL laser with a short wavelength of 850 nm. 1000BASE-SX standard has a minimum length of 220 meters and a maximum of 550 meters. The letter "S" stands for short wavelength, and the letter "X" for local area networks (LAN) and an 8B/10B encoding. The SX in 1000BASE-SX indicates that this version of Gigabit Ethernet is intended for use with short-wavelength transmissions over short cable runs of fiber optic cabling. 1000BASE-SX technologies are being widely implemented in enterprise-level networks and are primarily used between pieces of equipment within a building.

1000BASE-LX is a gigabit Ethernet fiber optic standard which has a working distance of up to 5 km over single-mode optic fiber. 1000BASE-LX can also be used to transmit data over common multi-mode fiber options in which case it has a maximum length of 550 meters. The "LX" in 1000BASE-LX stands for long wavelength, indicating that this version of Gigabit Ethernet is intended for use with long-wavelength transmissions over long cable runs of fiber optic cabling. 1000BASE-LX uses a long wavelength laser, and a maximum RMS (root mean square) spectral width of 4 nm.

1000BASE-LX10 is very similar to 1000BASE-LX, but achieves longer distances up to 10 km over a pair of single-mode fiber due to higher quality optics. 1000BASE-LX10, also known as 1000BASE-LX/LH or 1000BASE-LH. LX/LH stands for "long wavelength/long haul". LX is often used when networking a campus and LH can be used for runs across town to the local Internet service provider (ISP). 1000BASE-LX/LH SFP is single-mode by design, but when it gets together with its friend "mode conditioning patch cable", it can also be used for multi-mode application.

1000BASE-BX10 is capable of up to 10 km over a single strand of single-mode fiber, with a different wavelength going in each direction. The terminals on each side of the fiber are not equal, as the one transmitting downstream (from the center of the network to the outside) uses the 1490nm wavelength, and the one transmitting upstream uses the 1310nm wavelength.

1000BASE-EX is one of the non-standard mediums that are still used in the industry. Like the other 1000BASE-X standards, 1000BASE-EX is a gigabit Ethernet standard which is capable of data transmissions on working distances of up to 40 km over a single-mode optic fiber pair. It is very similar to 1000BASE-LX10 but achieves longer distances due to higher quality optics, running on 1310nm wavelength lasers. It is sometimes referred to as LH (long haul).

1000BASE-ZX is also a non-standard but multi-vendor term to refer to Gigabit Ethernet transmission using 1550nm wavelength to achieve distances of at least 70 km (43 miles) over single-mode fiber. Some vendors specify distances up to 120 km (75 miles) over single-mode fiber, sometimes called 1000BASE-EZX. 1000BASE-ZX SFP supports link length of up to 80km on single mode fiber at 1Gbps.

There is a number of 1000BASE SFP optics that are available depending on the customer application and distance capability required. Fiberstore is a professional manufacturer and supplier, offering various kinds of 1000BASE SFP transceivers compatible for Cisco, Juniper, and Finisar, etc. For example, Cisco MGBLX1 1000BASE-LX SFP transceivers are cost-effective modules supporting 10km transmission distance with SMF; and Cisco GLC-ZX-SM 1000BASE-ZX SFP is fully compatible with Cisco devices.