Guide to 40 Gigabit Ethernet Cabling With MPO Technology
In the past decades, the network speed has a great leap from 10Mbit/s in 1983 to today’s 40/100 Gbit/s. Thus new technologies have been developed to support the new transmission rate. Of which MPO technology with multifiber connector make the migration to 40/100 Gigabit Ethernet easier and more efficient, as it offers ideal conditions for setting up high-performance data networks in data centers to achieve greater bandwidth and handle future requirements. This article will briefly introduce the basics of MPO technology and its utilization in 40G Ethernet.
Shedding Light on MPO Connector
It is known that MPO connectors (known as multi-fiber push-on or multi-path push-on) can contact up to 72 fibers in a single connection. A connection must be stable and its ends correctly aligned, which is essential for achieving the required transmission parameters. A defective connection may even damage components and cause the link to fail altogether. MPO connectors are available in a female version (without pins), or a male version (with pins) as shown in the following picture. Noses and guide grooves (key) on the top side are the two other clearly visible features, which ensures the adapter hold the connector with the correct ends aligned with each other. Based on the placement of the key, two types of MPO adapters are available. One is “key-up to key-down”. It means the key is up on one side and down on the other. The two connectors are connected turned 180° in relation to each other. The other one is “key-up to key-up”. It means both keys are up. The two connectors are connected while in the same position in relation to each other.
Three Common Types of MPO Cables
MPO cable has the advantages of shorter installation times, tested and guaranteed quality and greater reliability. It has several different kinds of types.
Trunk Cables: trunk cables serve as a permanent link connecting the MPO modules to each other. They are available with 12, 24, 48 and 72 fibers. Their ends are terminated with 12-fiber or 24-fiber MPO connectors according to customer’s choice. These trunk cables like 12 fibers MPO trunk cable could help to create a simple, cost-effective 40G networking by installing a structured cabling system. MPO trunk cable requires greater care in planning but has a number of advantages, such as higher quality, minimal skew, shorter installation time, better protection, smaller volume of cable and lower total costs.
Harness Cables: harness cables provide a transition from multifiber cables to individual fibers or duplex connectors. For instance, 8 fibers 12 strands MPO harness cable has eight LC high fiber density connectors and a MPO connector, which is convenient for wiring and management system in 40G network with stable performance.
Y Cables: Y cables are generally used in the 2-to-1 version. A typical application is to join two 12-fiber trunk cables to a 24-fiber patch cord as part of a migration to 100 GbE. The rather rare version of 1 to 3 allows three eight-fiber MTP connectors to be joined to a 24-fiber permanent link, e.g. for migration to 40 GbE.
MPO Technology in 40 Gigabit Ethernet Cabling
OM3 and OM4 fiber optic cables terminated with MPO/MTP connectors are dispensable for parallel optical connection. These are the ingredients for 40 GbE technology in a structured cabling environment. Parallel optical channels with multifiber multimode optical fibers of the OM3 and OM4 are used for implementing 40 GbE. The small diameter of the optical fibers poses no problems in laying the lines, but the ports suddenly have to accommodate four or even ten times the number of connectors. This large number of connectors can no longer be covered with conventional individual connectors. So 802.3ba standard incorporated the MPO connector for 40GBASE-SR4. 40GBASE-SR4 QSFP+ modules like QSFP-40G-SR4 can support link lengths of 100 meters and 150 meters, respectively on OM3 and OM4 multimode fibers with a 12-fiber parallel MPO/MTP female connector. We can achieve 10G to 40G migration up to 100m or 150m, respectively on OM3 and OM4 MTP to LC break out cable as shown in Figure 2.
Some Tips About MPO Connection
- Always use one male connector and one female connector plus one MPO adapter when creating a MPO connection (see the following picture).
- Never connect a female to a female or a male to a male. It should be connected with a male and a female as stated above. 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 a MPO connector. The pins are difficult to detach from a MPO connector and the fibers might break in the process. In addition, the warranty becomes null and void if you open the connector housing.
Featured by its high density, flexibility and reliability with scalable, upgradeable properties, MPO technology can better satisfy the increasing need to upgrade to 40/100G. Just don’t forget to follow the above connection rules. Fiberstore provides wide brand compatible 40GBASE-SR4 QSFP+ transceivers and all kinds of MPO cables. FTL410QE2C is compatible Finisar 40GBASE-SR4 QSFP+ that is offered with high quality and low price. Each fiber optics has been tested to ensure its compatibility and interoperability.