SFP Modules

SFP, an acronym of SMALL FORM-FACTOR PLUGGABLE, is a compact and hot-pluggable transceiver used for both telecommunication and data communication applications. It connects motherboards of network devices (such as switches and routers) with optical or copper cables. By doing this, it converts Gigabit electrical signals into optical signals, and vice versa. The common match for SFP ports are copper SFP module applied with network cable and fiber SFP module applied with fiber optic cable. Network cable or copper cable includes Cat5e, Cat6, Cat6a, etc. while fiber optic cable includes single mode fiber and multimode fiber. A copper SFP module inserted into a SFP port has a RJ45 connector. It can transmit data within 100m over copper twisted pair cable. And the data transmission rate can reach up to 1000 Mbps. It is normally divided into two types, 1000BASE-T and 1000BASE-TX copper SFP. The former uses the IEEE 802.3ab standard using four bidirectional copper pairs, and each pair supports a data rate of 250 Mbps. While, the latter uses the TIA/EIA-854 standard using two unidirectional copper pairs (one pair for transmitting, one for receiving), each of which supports a data rate of 500 Mbps. A fiber SFP module inserted into a SFP port has a LC duplex interface. It consists of seven types, namely 1000BASE-SX, 1000BASE-LX, 1000BASE-LX10, 1000BASE-LX/LH, 1000BASE-LH, 1000BASE-EX and 1000BASE-ZX. SFP ports are found in Ethernet switches, routers, firewalls and network interface cards, etc. If you want to transfer data in 100m, then either a copper SFP or fiber SFP is a right choice to match the SFP port. If you want to transfer data over 100m, then a fiber SFP is needed.