SFP, SFP+ and XFP are all terms for a type of transceiver optics that plugs into a special port on a switch, router or other network device to convert the port to a copper or fiber interface. The commonly used SFP, SFP+ and XFP are all with LC connector. SFP and SFP+ with an identical pinout that is different with XFP optics. Both SFP+ and XFP with DDM function as default, whereas SFP partly support DDM function.

40Gbps QSFP+ ports are very popular in IDC. Then, do you know how to choose the most suitable product for your networking infrastructure? It refers to the link length, fiber applied, devices to be connected etc. For 1~5m link length, 40G QSFP+ DAC is the ideal choice for data center. QSFP+ DAC owns advantages: Lower Power Consumption: as DAC cables all are passive direct-attach copper cables, no power consumption;

In the 40GbE and IB-FDR(56Gb) interconnect solutions, 40Gb QSFP+ transceivers account for a large percentage of the market share. QSFP+ SR4, QSFP+ eSR4, QSFP+ IR4 and QSFP+ LR4 are the most popular optical modules. QSFP+ SR4(QSFP-40G-SR4) offers 4 independent transmit and receive channels, each capable of 10Gbps operation for an aggregate data rate of 40Gbps over 100 meters on OM3 multi-mode fiber(MMF) or over 150 meters on OM4 MMF. QSFP+ eSR4(QSFP-40G-CSR4) that works in the same principle as SR4, can be considered an enhanced QSFP+ SR4. 40GBASE-eSR4 QSFP+ Modules extend the reach of the IEEE 40GBASE-SR4 interface to 300 meters and 400 meters on laser-optimized OM3 and OM4 MMF respectively.

The SFP+ interface offers the highest density, lowest cost, and lowest power 10 Gigabit Ethernetsolution commercially available today. Further SFP+ enables mass migration of the 1GbE network to10 GbE by offering a very low cost 10GSFP+Cu (direct attached copper cable assembly) option for short reach interconnects along with multimode and single mode fiber options. The SFP+ interface accepts along with hot-pluggable, small-footprint, optical transceivers, a Direct Attach Cable “10GSFP+Cu”, which replaces two optical modules and a connectorized optical fiber with a twinaxial copper cable assembly. The 10GSFP+Cu option is defined for 10GbE applications over passive copper with a reach of 8.5m. The 10GSFP+Cu link utilizes a receive equalizer in the host PHY/SerDes in order to compensate for the Inter Symbol Interference (ISI) introduced by the cable. Electrical and mechanical specifications for SFP+ optical modules, 10GSFP+Cu, and hosts are defined in the SFF-8431 specification developed by the SFF Committee, with broad industry participation.