With 40GBASE-T standards and Category 8 cabling in development and only a few years away, many looking to upgrade today are asking if 10GBASE-T and Category 6A cabling is the right investment option.
The answer isn’t a simple one. From cost and availability, to power consumption, distance and cabling media characteristics, there is plenty to consider.
According to a recent Hewlett-Packard (HP) white paper, 10GBASE-T and Category 6A cabling costs less than using either optical fiber or SFP+ direct attach copper (DAC) options that have been widely deployed to date for 10 Gb/s.
With a potentially large market for servers in the data center, as well as for high-end desktops and 802.11ac wireless applications in the LAN, the 10GBASE-T market is positioned to accelerate dramatically over the next few years.
We’ve already seen a rise in 10GBASE-T server adoption as the more than half million 10GBASE-T server ports that shipped in 2012 jumped to nearly 5 million in 2013. If this trend continues, 10GBASE-T port shipments will likely pass SFP+ DAC sometime in 2015. Switch manufacturers are also ramping up their offerings, and the price per port for 10GBASE-T has dropped significantly.
For example, the cost of a Cisco Nexus 3064-X 48 SFP+ & 4-QSFP Port Switch compared to a Nexus 3064-T 48 X 10GBASE-T & 4 QSFP+ Port Switch is now about the same. The street price can be as low as $250 per port for 10 gigabit, which can be 50% to 70% lower than MSRP. Both switches are rack-mountable 1U with similar features.
The big advantage of a 10GBASE-T is that it can interface directly with the 10GBASE-T port on the server and there are no potential compatibility issues that can happen when using SFP+ DAC cables. Furthermore, the cost of 10GBASE-T remains much less than optical transceivers and optical fiber cabling.
There are several reasons behind the growing success of 10GBASE-T and Category 6A. First of all, Category 6A cabling offers a much longer reach than passive SFP+ DAC—100 meters versus 7 meters. This offers greater design flexibility and supports the growing popularity and economics of end of row (EoR) topologies in the data center.
Unlike SFP+ DAC, Category 6A also has the advantage of being an interoperable, standards-based technology that provides backwards compatibility with legacy Gigabit or 100 Megabit Ethernet networks via autonegotiation.
One of the previous barriers to 10GBASE-T adoption was the power consumption per port compared to other 10 Gb/s options. However, improvements in technology have significantly decreased power use to the point where it’s not significantly more than SFP+ DAC in short-reach mode, which at up to 30 meters, still offers a greater distance.
The diameter of Category 6A cable has also been an obstacle to deployment. Fortunately, the next generation of Category 6A cable is smaller at about 7 mm (0.275 inch) in diameter.
Even smaller diameter cables using finer gauge conductors can be manufactured to support 10GBASE-T for shorter distances. However, these cables couldn’t technically be considered standards-based Category 6A compliant.
If you need to deploy 10 Gb/s today, 10GBASE-T is certainly well positioned as a more cost effective technology than other alternatives for switch-to-server and switch-to-switch connectivity for distances up to 100 meters.
While still a few years off, the ability to hold out for 40GBASE-T and Category 8 depends on your specific situation. There is some good news, as well as some considerations.
40GBASE-T is specified with transmission performance up to 2 GHz (four times the bandwidth of Category 6A) with a lot more stringent alien crosstalk requirements. To meet these requirements, you are looking at a shielded cabling system, similar in design to Belden's 10GX shielded cabling but specified to 2 GHZ.
40GBASE-T and Category 8 will also likely be a pre-terminated solution. The good thing is that the cable diameter will likely not be any larger than existing Category 6A.
The maximum reach for 40GBASE T is 30 meters, which will be sufficient for most switch-to-server connections in a data center for EoR topologies. The good news is that that because of the shorter distances, the power consumption for 40GBASE-T should be no more than 10GBASE-T.
As you look at the considerations and your timeline to upgrade, Belden has the experts on hand to discuss all of your options and help you determine your best course of action. Please don’t hesitate to ask us any questions about deploying 10GBASE-T and 40GBASE-T by scheduling a call with our experts or posting a comment below.
Looking back at his 42-year career in the cabling industry, Paul Kish was one of the founding fathers of the industry. Retiring from Belden in 2015, Paul was recognized as an expert in cable transmission. He served as a role model, an innovator and a thought leader. Paul was a key contributor to the development of cabling standards with TIA, ISO and IEEE, and also served on the BICSI Technical Information & Methods Committee.