We know that MTP/MPO cable is a great option for nowadays data center fiber optic cabling which needs higher and higher cabling density and transmission capability. In most cases, 12-fiber MTP cable is used to realize 10G to 40G or 40G to 40G connection. However, there is a problem in this cabling system—only eight fibers of the 12-fiber MTP cable are used (four fibers for transmitting and four fibers for receiving), leaving the middle four fibers unused. That means using 12-fiber MTP cable cannot achieve 100% fiber utilization. To solve this problem, MTP conversion cable is available on the market. And this article is going to introduce applications of MTP conversion cable in data center.
This type of MTP conversion cable is usually used for 40G to 120G connection. It is terminated with one 24-fiber MTP connector on one end and three 8-fiber MTP connectors on the other end. As shown in the following figure, a 120G CXP transceiver is plugged into the 100G CFP interface on the switch on the one side, while three 40G QSFP+ transceivers are plugged into the 40G QSFP+ interfaces on the switch on the other side. Then the 1×3 MTP conversion cable connects the 120G CXP transceiver with the three 40G QSFP+ transceivers—the 24-fiber MTP connector terminated at the cable is directly plugged into the CXP transceiver, while the three 8-fiber MTP connectors are plugged into the three QSFP+ transceivers. In this way, 40G to 100G migration can be realized smoothly.
This type of MTP conversion cable can be used for 10G to 40G or 40G to 40G connection. It is structured with two 12-fiber MTP connectors on one end and three 8-fiber MTP connectors on the other end. For 10G to 40G connection, MTP fiber optic cassette is also needed. As shown in the following figure, three 40G QSFP+ transceivers are plugged into the 40G QSFP+ interface on the switch on the one side, while twelve 10G SFP+ transceivers are plugged into the 10G SFP+ interfaces on the switch on the other side. Then the three 8-fiber MTP connectors terminated at 2×3 MTP conversion cable are directly plugged into the three 40G QSFP+ transceivers, while the two 12-fiber MTP connectors are plugged into the MTP 12 fiber adapters mounted at the rear of the MTP fiber optic cassette. With one end of twelve duplex LC patch cables plugged into the LC adapters on the front side of the cassette and the other end of the twelve cables plugged into twelve 10G SFP+ transceiver, the 10G to 40G connection is accomplished.
For 40G to 40G connection, we can use a MTP adapter panel. From the figure below, we can find that the connections on both sides are symmetrical. The three 8-fiber MTP connectors at the end of 2×3 MTP conversion cable are directly plugged into the three 40G QSFP+ transceivers, then into 40G QSFP+ interfaces on the switch. And the two 12-fiber MTP connectors of both two MTP conversion cables are plugged into MTP 12 fiber adapters on the MTP adapter panel.
It is not difficult to find that the three cabling solutions above make use of all the fibers. Therefore, data center managers can gain great value to utilize MTP conversion cable which can achieve 100% fiber utilization as well as meet the demand for high density cabling.