Patch Cord is needed for a QSFP Transceiver
Switches are the first connecting devices that aggregate the 40G links; in order to achieve that, 40G transmission networks need advanced switches with matching patch cords and transceiver modules. Many servers in data centers today can support Ethernet transmissions of 40G where 40G QSFP transceivers are considered to be the most economical solution for these high-speed links.
Difference between Single-mode and Multimode Fiber Patch Cords for QSFPs The first factor that needs to be considered is the cable fiber type. This is because of the transmission characteristic optical signals of the fiber optic QSFP module. The optical signals perform different over different wavelengths. And optical signals with the same wavelength perform totally different when they run through different types of cables.
Parallel optical QSFP transceivers used for 40GBASE-SR4 and 40GBASECSR4 have 10-Gbps electrical lanes that are mirrored in the optical outputs and thus require a cable with eight fibers with an MPO / MTP connector interface.
Single mode optical transceivers used for 40GBASE-LR4 use the same 10-Gbps electrical lanes, which are then combined in the optical outputs, thus requiring two fibers with an LC duplex connector interface. 40G QSFP transceivers with MPO / MTP interface are designed for short transmission distances and Single mode LC Duplex QSFPs for long transmission distance. Applications are supported by 40G QSFP InfiniBand SDR/DDR/QDR Fibre Channel/Fibre Channel over Ethernet (FCoE) Storage Area Networks (SAN)
Network Attached Storage Switched Fabric I/O
High density connections between networking equipment Data center cabling infrastructure The optical QSFP modules with MPO / MTP connector can be connected with two different cabling variants: One is 40G QSFP to 40G QSFP with a MPO / MTP trunk cable which connects the modules 1:1 and the other one is to connect 40G QSFP to 4x10G SFP+ with a MPO/MTP to 4xLC breakout cable.
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