Generally, the MPO cables and connectors can be utilized in 3 ways which are MPO/MTP adaptors, MTP/MPO-LC Cassette, MTP-LC Breakout Patch Panel, Transceivers With MTP/MPO Interface, MPO/MTP breakout cables are an exception for this methods.

1. MPO/MTP adaptors

Each individual MPO element (trunk, adapter, patchcord) is classified by type (A, B, or C) and contributes to maintaining the required polarity so that the right transmitter communicates with the right receiver. 

But when referring to the end-to-end system, standards refer to the “connectivity method,” which can also be A, B, or C. This should not be confused with the type of each individual element. An A, B, or C connectivity method corresponds to the type of the MPO trunk cable only.For example, a Method A connection for end-to-end parallel signals will use 1 Type A trunk, 2 Type A mating adapters, 1 Type A patch cord on one end, and 1 Type B patch cord on the other end. Shown here is a “key-up-to-key-down” mating setup for MPO connectors. This method is used to maintain fiber polarity.

 2. MTP/MPO-LC Cassette: Plug-and-Play for Fast Installation

MTP/MPO fiber cassette modules are fitted with 12 or 24 fibers and have LC, SC or E2000 adapters on the front side and MTP/MPO connector at the rear. Thus enables users to take the fibers brought by a trunk cable and distribute them to a duplex LC cable. It is an enclosed unit that houses 8, 12, or 24 fiber factory terminated fan-outs inside. MTP/MPO cassette allows for the rapid deployment of high-density data center infrastructure and supports improved troubleshooting and reconfiguration during MACs.

3. MTP-LC Breakout Patch Panel: Pave the Way for 40/100G Migration

Data traffic keeps accelerating and legacy 10/25G systems are hardly enough for it, making migration to higher-speed 40/100G imperative. The 96-fiber MTP-LC breakout patch panel can assist in making the transition: use MTP cables to connect your 40/100Gb switches to the rear ports of the panel, then add duplex LC cables to connect your 10 Gb devices to the breakout panel‘s front ports. This MTP-LC breakout patch panel is designed with a removable cable management plate at the back, it effectively simplifies trunk cable organization, facilitates installation and reduces cable clutter.

4. Transceivers With MTP/MPO Interface

Nowadays, various 40G transceivers are available on the market, but mainly there are two interfaces adopted by 40G QSFP+ transceivers—MTP/MPO and LC. Generally, the 40G QSFP+ transceivers with LC interface are used for long distance transmission over single-mode fiber (SMF), and QSFP+ transceivers with MTP/MPO interface are utilized for short distance transmission over multimode fiber (MMF). However, for some 40G transceivers with MTP/MPO interface, such as 40GBASE-PLRL4, and 40GBASE-PLR4, they can support long distance transmission over SMF.

Connection rules

I can suggest some of the thumb rules when consider connecting the MPO/MTP cables and those areas below.

·      When creating an MPO connection, always use one male connector and one female connector plus one MPO adapter.

·      Never connect a male to a male or a female to a female.

    With a female-to-female connection, the fiber cores of the two connectors will not be at the exact same height because the guide pins are missing. 

    That will lead to losses in performance.A male-to-male connection has even more disastrous results. 

    There the guide pins hit against guide pins so no contact is established. This can also damage the connectors.

·      Never dismantle an MPO connector - The pins are difficult to detach from an MPO connector and the fibers might break in the process.