MPO connector is originally designed for ribbon fiber and available in 12, 24, 48 and 72 fiber variants. Generally, there are two popular MPO connector types: 12-fiber MPO connector and 24-fiber MPO connector.
12-Fiber MPO Connector
A 12-fiber MPO connector can deliver 6x10G transmit fibers and 6x10G receive fibers. Actually 8 fibers were being used at the transceiver and 4 were just spares. The 12-fiber MPO connector was not the best backbone choice in the long term as no one could really foresee how the industry would evolve.
Accommodating 12 fibers, the 12-fiber MPO connector provides up to 12 times the density, thereby offering savings in rack space. It is the first connector having enough repeatable performance to be accepted in data centers. If you build a backbone with a 12-fiber MPO connector, basically you can put any connection on the end to be future proofed (LC, SC, etc.). Thus most of data centers are built with 12-fiber MPO cabling in the backbone and MPO-LC harnesses connecting to equipment like switches and servers. Many equipment today still has an LC transceiver interface, therefore the harness is required to convert from MPO in the backbone to LC at the port.
Every equipment coming into the data center was either 40G (8 fibers) or 100G (24 fibers). 12 is not divisible by 8, but 24 is. If you combine 2×12 fiber MPO connectors in the backbone, you can connect 3×8 fiber MPO connectors with zero fiber wasteage at the switch. The 24-fiber MPO connector has similar performance to the 12 if not exactly the same.
The 24-fiber MPO connector has two rows of 12 fibers. And this additional row of fibers requires an increase in the spring force to push all of those fibers together, actually double what you need for 12. With the same size as a 12-fiber MPO connector, the 24-fiber MPO connector has double the amount of fibers and reduces the amount of cable required at the back end because a 24 fiber cable is only marginally bigger than a 12 fiber cable. Moreover, why combine 2×12 fiber MPO connectors to make 3×8 when you can just have 1×24 fiber MPO connector converting to 3×8? The 24-fiber MPO connector can also satisfy the demand for 100G data rates over a single connector. 20 fibers are required for 100G (10x transmit and 10x receive).
MPO connector delivers the optical, mechanical and environmental performance that service providers need to expedite the addition of fiber capacity and to support higher data-rate services. It plays an important role in the high-density cabling solutions.
