Base-16 is an MPO plug and play cabling system that utilizes an MPO-16 connector vs. the MPO-12 connector that is used for more commonly in Base-8 or Base-12 cabling systems. The MPO-16 connector has specifications that are defined in TIA-604-18 released in 2018 and IEC 61754-7-1 released in 2014, but the connector has seen limited market adoption.
With the recent introduction and promotion of Base-16 systems by some manufacturers, the time is right to share some helpful insights.
No. Only one currently available 400G Ethernet application requires an MPO-16 connector – 400GBASE-SR8. All other current and planned IEEE 400G Ethernet applications use 2- or 8-fibers. There is expected to be very little market adoption of 400GBASE-SR8 because it uses the MPO-16, with almost no installed base. In addition, the SR8 application requires an MPO-16 with an Angled Polish Connector (APC) end-face, which is not standard for multimode fiber systems and may require specific installation and testing requirements. For 800GbE, there are several options that will utilize 2- or 8-fibers with an LC or MPO-12 interface.
No. The MPO-16 connector does not mate with MPO-12 connectors used in Base-8 or Base-12 systems. The MPO-16 connector has different alignment pin spacing and has an offset key vs. a centered key. This means you cannot directly connect an existing Base-12 or Base-8 system to a Base-16 system.

Yes. The Base-16 cables are typically 20-30% larger than Base-8 cables with the same fiber count. Here are some examples:
Due to all the above reasons, Siemon continues to act as a trusted advisor to our clients and recommends Base-8 systems for new installations and will continue to only recommend solutions that solve problems, make sense for a given customer application, and are cost-effective.
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