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Cabling Connectivity for 40G Short Reach Transceivers Originally the Ethernet standard has relied on duplex fiber cabling with each channel using one fiber to transmit and the other to receive. Later, the 802.3ab standard requires multiple lanes of traffic per channel. So some of 40 Gigabit transceivers uses parallel optic transmission technology which spatially multiplexes or divides a high-data-rate signal among several fibers that are simultaneously transmitted and received. This article will introduce cabling connectivity for 40G short reach parallel optic transceivers.
40G Short Reach Transceivers 40G parallel optical transceivers use four 10G channels to transmit and four 10G channels to receive over one 12-fiber assembly. The middle four fibers remain unused, or dark. Each fiber either transmits (Tx) or receives (Rx) 10G traffic at a single wavelength. The QSFP+ transceiver is the dominant transceiver used for 40 Gigabit Ethernet applications. In 2010, 40GBASE-SR4 parallel optics solution for MMF was released by IEEE standard 802.3ba as one of several 40G based solutions. Since then, some other engineered solutions have been released, including 40GBASE-CSR4, which is similar to 40GBASE-SR4 but extends the distance capabilities. The following table tells more details about these two short reach 40G parallel optical transceivers.
Fiberstore (FS.COM) | Cabling Connectivity for 40G Short Reach Transceivers