40G transmission is very common in the backbone network now. However, not all the devices and network are upgraded to 40G. To adapting the network between devices and network of different data rate. It is necessary to connection 40G devices to 10G devices for network interconnection. To solve this problem, fanout technology is be accepted and widely used in data center. Fanout products for interconnection is easy to understand. It’s kind of like the water pipeline in our building: water is transferred from the trunk pipeline in a building. Then trunk pipeline fans out into several pipelines that have smaller diameters to bring the water to every house. This post will introduce several Fanout products that are commonly used for 40G data center interconnection.40G MPO Fanout Cables
The first fanout component is 40G MPO fanout cable, also called breakout cable or harness cable. MPO fanout cable is a multi-fiber optical cable with one end terminated with a male/female MPO connector and the other end attached with several LC connectors. Actually, there are various types of MPO fanout cables, according to connector type, cable length and cable type. But they all have the similar structure. Here will introduce three most popular MPO fanout cables according to the package type.
The first one to be introduced is also what most customer need. This cable is fan out into 12 fibers or 24 fibers. The above picture shows a typical 12-fiber MPO harness cable. The MPO connector of this fanout cable is linked to 6 duplex LC connectors, which is really useful for backbone cabling from 40G devices to 10G devices.
The second one is a little bit smaller version of the former. The fibers are fanout directly from the MPO connectors. With small size, this kind of mini MPO harness cable can be easily put into patch panel and increase the cabling density largely and effectively.
The third to be introduced is a special one—MPO cassette. Literally, it looks like a cassette and looks very different from other MPO fanout cables. However, when you look inside the cassette, it has not much difference from other MPO fanout cables. MPO Cassette actually contains one or several mini MPO fanout cables in side the cassette, which is designed for those who want have everything in clean and tidy status. As it can be installed in a standard rack and the cables are all well protected. A 12-fiber MPO cassette usually has a 12-fiber mini MPO fanout cable in side the cassette, with a MPO connector on the backside and 12 LC connector in the front. For a 24-fiber MPO cassette, there could be a 24-fiber fanout cable or two 12-fiber cables inside. The following picture is a MPO cassette with two 12-fiber MPO fanout cable inside it, thus there are two MPO connector on its backside.
40G Fanout Direct Attach Cables
To decrease the 40G interconnection cost, Direct attach cable (DAC) is being widely used. There are also fanout versions of 40G DAC which support 40G to 10G cabling. These kind of 40G DAC usually have one QSFP+ connector on one end and four SFP+/XFP connectors or several LC connectors at the other end. For example, the following is 40G QSFP+ to 8 LC DAC. The QSFP+ connector of it can be used to plug in the 40G device which has QSFP+ port. On the other end, the four duplex LC connectors are used to separately connect four SFP+ transceivers , which are used to plug in 10G devices with SFP+ switched (shown in the following picture). If you used a 40G QSFP+ to 4 SFP+ DAC, this process would be easier, cause the SFP+ connector can be plugged into the SFP+ switch directly.
All in all, fanout technology plays an important role in the 40G data center for both connecting devices supporting different data rate and distribution. Most fanout products are factory pre-terminated. The installation and maintenance doesn’t need many skills. In FOCC, a variety of fanout products of high quality and reliability can be customized according to your application.