Monthly Archives: November 2017

Datasheet of 40G QSFP Module

When it comes to selecting 40G QSFP modules, customers may be dazzled by the various products provided by various suppliers. Some of them may directly purchase from big brands like Cisco. Actually, except for those well known brands, many other rising companies like FS also provide 40G QSFP transceivers, which usually come at a much lower price with with a high quality. This post will demonstrate the 40G QSFP Datasheet provided by FS.

40G QSFP Datasheet: QSFP 40G SR4 Datasheet

The S-Class FS 40GBASE-SR4 QSFP module supports link lengths of 100 and 150 meters, respectively, on laser-optimized OM3 and OM4 multimode fibers. QSFP 40G SR4 transceiver is aligned to IEEE 40GBASE-SR4 optical specifications which support high-bandwidth 40G optical links over 12-fiber parallel fiber terminated with MPO/MTP multifiber female connectors. Because IEEE 40GBASE-SR4 does not support 4x10G breakout connectivity to 10GBASE-SR, see QSFP-40G-SR4 or QSFP-40G-CSR4 for such applications. QSFP 40G SR4 does not support FCoE. More specific details of FS QSFP 40G SR4 Datasheet can be obtained in the table below.

40g qsfp sr4 datasheet

40G QSFP Datasheet: QSFP 40G LR4 S Datasheet

The FS 40GBASE-LR4 QSFP module supports link lengths of up to 10 kilometer over a standard pair of G.652 SMF (single-mode fiber) with duplex LC connectors. The QSFP-40G-LR4-S module supports 40GBASE Ethernet rate only. The 40 Gigabit Ethernet signal is carried over four wavelengths. Multiplexing and demultiplexing of the four wavelengths are managed in the device. QSFP-40G-LR4-S does not support FCoE. More information have been shown in the following QSFP 40g LR4 S Datasheet.

QSFP 40G LR4 datasheet

QSFP+ SR4 vs QSFP+ LR4: Which One to Choose?

After going through QSFP 40G SR4 Datasheet and QSFP 40g LR4 S Datasheet, you may have had a basic understanding of QSFP 40G SR4 and QSFP 40g LR4. SR is short for short reach and LR represents Long Reach. The most obvious difference is that 40GBASE-SR4 is with MPO/MTP port while the 40GBASE-LR4 is with the Duplex LC port. The cost of 40GBASE-SR4 QSFP+ is more cheaper than the 40GBASE-LR4 QSFP+. Additionally, the fiber cost of the cabling with them also have a big difference. Because SMF cabling is more expensive than the MMF cabling.

Summary

As speeds have increased to 40G, the quad small form-factor pluggable (QSFP) has become the high-density transceiver of choice. Hoping this post on FS 40G QSFP Datasheet may help you when selecting 40G optical transceivers.

Fiber Optic Connector Selection Guide

For the past few decades since 1980s, many different types of fiber optic connectors such as MTP connector and MPO connector, have been provided by various manufacturers. Despite the fact that these types of optical connector varies greatly in mechanical design, the most basic components a fiber connector are more or less the same. They all have a fiber ferrule,  connector sub-assembly body, connector housing, and stress relief boot, etc. Next, part of the most commonly seen connectors will be introduced to you one by one.

LC connector

It works in both simplex and duplex with 1.25mm ferrule. Available in single mode and multimode. Externally LC connectors resemble a standard RJ45 telephone jack. Internally they resemble a miniature version of the SC connector. LC connectors use a 1.25mm ceramic (zirconia) ferrule instead of the 2.5mm ferrule. LC connectors are licensed by Lucent and incorporate a push-and-latch design providing pull-proof stability in system rack mounts. Highly favored for single mode applications.

LC connector

MTP connector and MPO connector

MTP connector and MPO connector are compatible ribbon fiber connectors based on MT ferrule which allow quick and reliable connections for up to 12 fibers. They are intended for installations that require many fiber connections. Up to 12 fibers in a ribbon are stripped to 125um cladding and inserted into 250um spaced parallel grooves. The ferrule also includes two 0.7mm diameter holes, running parallel to the fibers on the outer side of the ferrule. These two holes hold precision metal guide pins which align the fibers with tight tolerances.

MTP connector

MTP connector and MPO connector feature male and female connector design. Male connectors have two guide pins and female connectors do not. Both connector types need an adapter to mate a pair of male and female connectors. Because MTP connector and MPO connectors are trying to align so many fibers at once, their coupling loss are typically bigger than single fiber connectors.

ST Connector

ST connector comes in simplex with a twist-on mechanism, and it is available in both single mode and multimode. It is the most popular connector for multimode fiber optic LAN applications . It has a long 2.5mm diameter ferrule made of ceramic (zirconia), stainless alloy or plastic. Unlike MTP connector and MPO connector it mates with a interconnection adapter and is latched into place by twisting to engage a spring-loaded bayonet socket.

ST connector

Summary

Whether you are installing a brand new fiber optic network or repairing a legacy system using , hope this fiber optic connector selection guide will help you determine what kind of connector you are looking at or what type of connector you need to replace.