Data Communication

As 10G network no longer satisfies the increasing demand for high speed data transmission, many data center managers turn to 40G network. Base-2 connectivity, based on increments of two fibers, is a common type of fiber optical link in 10G network. However, this kind of connectivity is not suitable for 40G network which needs high-density cabling. For 40G network cabling, there are two popular solutions—Base-8 connectivity and Base-12 connectivity. How much do you know about these two cabling solutions? Is there any difference between them? After reading this article, you will find the answer.

In Base-12 system, Base-12 connectivity makes use of fiber optical links based on increments of 12 fibers. And 12-fiber or 24-fiber MTP/MPO optical connector assemblies are usually used to accomplish the links, such as 12-fiber or 24-fiber MTP trunk cable. Here is a figure of 24-fiber trunk cable used in Base-12 system for you.

The Base-8 system still uses the MTP/MPO fiber connector, but the links are built in increments of 8 fibers (as shown in the following figure). Thus 8-fiber trunk cable, 16-fiber trunk cable and 24-fiber trunk cable can be easily found in Base-8 system. Here is a figure of 24-fiber trunk cable used in Base-8 system for you.

Since the number twelve is obviously larger than the number eight, Base-12 connectivity does provide the benefit of connector with higher fiber density compared to Base-8, and thus a larger number of fibers can be installed more quickly when using Base-12 connectivity. However, as 8-fiber transceivers are utilized in most deployments of 40G network, the benefit of matching the fiber count in the MTP backbone connectivity with the fiber count of the transceiver tends to outweigh the density benefit of Base-12 connectivity. In addition, in Base-12 connectivity, four fibers for transmit and four fibers for receive, leaving four fibers unused per connection. This will lead to a significant and costly loss in fiber network utilization. But Base-8 connectivity can be a more cost-effective option for end-to-end MPO to MPO channels and architectures. In fact, Base-8 connectivity is not an universal solution and Base-12 connectivity in some cases may still be more cost-effective. The following part describes the relative benefits when comparing Base-8 versus Base-12 connectivity for a data center deployment.

• Optimized for both 2-fiber and 8-fiber transceiver technologies.
• Enables 100% fiber utilization for 8-fiber transceiver systems without the additional cost and insertion loss of Base-12 to Base-8 conversion devices.
• Cable harnesses can easily route to all common port counts on switch line cards.
• Only requires unpinned MTP patch cords for any connections within the link.
• Most flexible solution for 40G, 100G and 400G transmission networks.

• Higher fiber per connector density than Base-8 connectivity.
• Compatible with the large installed base of existing Base-12 MTP deployments.
• Where proprietary vendor specific 40G duplex 2-fiber transceiver technologies are deployed, existing Base-12 data center infrastructures offer higher fiber density per connector (Note: the vendor specific technologies are incompatible with each other, and with parallel optics,which may add a level of management complexity in a multi-vendor environment.)

Base-12 connectivity has dominated the 40G network market for years, while the Base-8 connectivity is an additional option to ensure that data centers have the most cost-effective, future-proof network available. And both of them have their own benefits. As for which one to choose, it depends on the requirements of the network deployment. I hope this article can help you have a better understanding of this two cabling solutions.