SFP is a compact, compatible and hot-swappable transceiver, which is widely utilized in telecommunications and data communications. There are a lot of SFP transceivers available to support short or long distance transmission. They can be intermixed in combination of IEEE 802.3z standard compliant with 1000BASE-SX, 1000BASE-LX, 1000BASE-LX10 or 1000BASE-ZX interfaces on a port-by-port basis. This post mainly illustrates 1000BASE SFP for Gigabit Ethernet transmission.
Gigabit Ethernet (GbE or 1 GigE) is a term describing various technologies for transmitting Ethernet frames at a rate of a gigabit per second (1,000,000,000 bits per second), as defined by the IEEE 802.3-2008 standard. The initial standard for Gigabit Ethernet was produced by the IEEE in June 1998 as IEEE 802.3z. There are many specifications of IEEE 802.3z displayed by the following table.
| Name | Medium | Specific distance |
| 1000BASE-CX | Shielded balanced copper cable | 25 meters |
| 1000BASE-KX | Copper backplane | 1 meter |
| 1000BASE-SX | Multi-mode fiber | 220 to 550 meters dependent on fiber diameter and bandwidth |
| 1000BASE-LX | Multi-mode fiber | 550 meters |
| 1000BASE-LX | Single-mode fiber | 5 km |
| 1000BASE-LX10 | Single-mode fiber using 1,310 nm wavelength | 10 km |
| 1000BASE-EX | Single-mode fiber at 1,310 nm wavelength | ~ 40 km |
| 1000BASE-ZX | Single-mode fiber at 1,550 nm wavelength | ~ 70 km |
| 1000BASE-BX10 | Single-mode fiber, over single-strand fiber: 1,490 nm downstream 1,310 nm upstream | 10 km |
| 1000BASE-T | Twisted-pair cabling | 100 meters |
| 1000BASE-TX | wisted-pair cabling | 100 meters |
1000BASE SFPs in the above table are all categorized under IEEE 802.3z standard. The following passages aims at introducing three of them: 1000BASE-SX, 1000BASE-LX and 1000BASE-LX/LH.
1000BASE-SX SFP is compatible with the IEEE 802.3z 1000BASE-SX standard by utilizing a 770 to 860 nanometer, near infrared (NIR) light wavelength. It only supports multi-mode fibers with link lengths ranging from 220 meters to 550 meters. The commonly used 1000BASE-SX transceiver is 1.25Gbps 1000BASE-SX SFP 850 nm 550 m Multi-mode Optical Transceiver. This optical transceiver features high performance with a low price, suitable for 850 nm VCSEL laser and PIN photodetector for 550 meters transmission.
1000BASE-LX is a fiber optic Gigabit Ethernet standard specified in IEEE 802.3 Clause 38 by using a long wavelength laser (1,270–1,355 nm). It supports both single-mode and multi-mode fibers. It is specified to work over a distance of up to 5 km over single-mode fiber and 550 meters over multi-mode fibers. While talking about 1000BASE-LX SFP, 1.25Gbps 1000BASE-LX/LH SFP 1310 nm 10 km Single-Mode Optical Transceiver is more popular among consumers for Gigabit Ethernet and Fibre Channel Switch Infrastructure. A figure about this product is available.
1000BASE-LX/LH, called either 1000BASE-LX10 or 1000BASE-LH (Long Haul), is very similar to 1000BASE-LX, but achieves longer distances up to 10 kilometers over a pair of single-mode fibers due to higher quality optics. It consists of three sections: a FP laser transmitter, a PIN photodiode integrated with a trans-impedance preamplifier (TIA) and MCU control unit. It is applied in 1310 nm FP laser and PIN photodetector for 10 kilometers transmission.
On the whole, 1000BASE-SX, 1000BASE-LX, 1000BASE-LX/LH are all suitable optical modules for Gigabit Ethernet. The fiber types and transmission distance decide which kind or kinds of 1000BASE-X series SFPs are used. Fiberstore provides not only above mentioned SFP, but also other 1000BASE SFP transceivers. For further information about 1000BASE SFP transceivers, please visit Fiberstore.