Datasheet

40G Cabling Technical Q&A Document
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Q. What other options are available apart from break-out cables?
Using an MTP-LC fan-out with an MTP-12 at one end, a 40G interface can be adapted from one
port of 40G into 4x10G and uses the same cabling to convert multiple 10G links into a single cable.
In addition to using a fan-out cable, there are also a number of cabling system solutions that use a
“cassette” style system to break out the MTP into individual LC pairs (as below - (1) MTP-12 into (6)
LC pairs). For more information on various deployment methods for these cassettes in a QSFP+ to
SFP+ deployment, refer to the following document:
http://csmedia.corning.com/CableSystems//Resource_Documents/application_engineering_notes_rl/AEN152.pdf
An additional solution for deployment of 40G (QSFP+) channels with increased fiber utilization is to use
an MTP to MTP cassette system that converts 12-fiber MTPs to 8-fiber MTPs, as shown below. The
above document provides guidance and detailed information on this deployment method as well.
Q. Can the 40G-LR4 transceiver also be split into 4x10G connections?
A. No, 40G-LR4 cannot be split into 4x10G. The 40GBASE-LR4 uses 4 lambdas (or wavelengths)
on a pair of single mode fibers, and does not lend itself to “splitting” into 4 pairs without substantial
complexity to split out the wavelengths. The unique characteristic of 40GBASE-SR4 is that it uses
parallel (ribbon) fiber, which allows the creation of 4 fiber pairs.
As an alternative single mode parallel 40G optics are available (40G-PLRL4 and 40G-PLR4) that do
allow for splitting into 4x10G (single mode). Each of these optics is fully compatible with 10GBASE-
LR and 10G-LRL up to the maximum distance of each optic, and use single mode MTP-12 ribbon
fibers.