2.5 and 5.0G: Don't Bandage Your Wireless

The NBASE-T™ Alliance was established in 2014 with the goal of promoting technology to allow 2.5Gbps and 5.0Gbps to operate over Category 5e and Category 6 respectively. The IEEE has agreed to begin work on developing a standard in an attempt to squeeze more bandwidth from existing TIA category cabling specifications. The electronics manufacturers are promoting the reuse of existing cabling when deploying their technology. However, with a simple analysis, it is apparent that this strategy is only a temporary bandage to the infrastructure already beginning to sag under the demands of increasing applications and bandwidth consumption.


One of the main applications currently driving the need for higher bandwidth into the enterprise is the new 802.11ac wireless technology. The 802.11ac technology is being rolled out in multiple waves, and current wireless access points (WAPs) entering the market are capable of overfilling a single gigabit channel. Wave two WAPs are capable of transmitting 1.7 gigabits per second worth of IP traffic, making multiple 1 Gbps Category 6 cables necessary as pictured in FIGURE 1 below. When 802.11ac is fully rolled out, the WAPs will be capable of transmitting up to 6.9 Gbps and the next generation 802.11ax technology promises even higher throughput.

The NBASE-T Alliance estimates that it costs about $300 per cable pull, and that over 85% of the installed enterprise network infrastructure is either Cat 5e or Cat 6. On the surface it seems to make sense to try and extend the life of previously installed Cat 5e or Cat 6 however it is only prolonging the inevitable. The growth of 802.11ac is exceeding the original optimistic projections and has the fastest adoption rate of any wireless technology. The normal 4-6 year cycle of replacing equipment has shortened to 2-3 years and minimally compliant category 6 and 5e will quickly be saturated or left behind.  Not only will 802.11ac ramp to 6.9 gigabits per second, but as wireless speeds increase, the reach of each WAP goes down. Therefore, when a wireless owner decides to upgrade from 802.11n to 802.11ac, more WAPs will be needed to provide an increase in capacity while covering the same area. It stands to reason that new cable will need to be pulled, and if so, the logical choice would be to install Category 6A. TIA TSB-162-A recommends two (2) Category 6A cables per WAP to support the future growth of new wireless technologies. This is largely because in order to increase the network speed over the same area, next generation technologies will require more WAPs than the generation before, so why not pull an extra cable during the install. If the wireless owner wants a separate wireless network for guests, than it may make sense to pull four (4) Cat 6A cables to each WAP in order to minimize life cycle costs. Finally, consider the fact that the next generation wireless 802.11ax is expected to start where 802.11ac left off in only a few short years from now.

It should be noted that 2.5Gbps and 5.0Gbps are far from being tried and true technologies.  It is anticipated that these new BASE-T speeds will utilize 10GBASE-T silicon technology. Alien crosstalk was the limiting factor in determining network operating margins with category 6a channels and it remains to be seen how 10 to 20 year old Cat 5e and Category 6 channels will perform as their alien crosstalk was never specified. Additionally, bundled cables in combination with power over Ethernet (PoE) will further complicate the operating environment.  There are already discussions on creating a new TIA TSB-155 to address mitigation options with these underspecified channels. These Category 5e and 6 products that are minimally compliant to the standard could face difficulties operating at 2.5Gbps or 5.0Gbps up to 100 meters when next to or providing next generation 100W PoE (IEEE 802.3bt).

Due to increasing bandwidth consumption and network speeds, the next generation of wireless will require Category 6a to fully support the technologies. If the IEEE is successful, and is able to develop technology that allows reliable operation of up to 5.0Gbps over Category 6 products it is anticipated that the technology is eventually destined for desktop applications. While there are no desktop applications that currently require 10 gigabit per second, it is safe to say that bandwidth requirements are only going to grow over time. Installing a premium Category 6 product to your desktop that allows reliable 5.0 gigabit per second performance is worth considering. Berk-Tek’s LANmark™-1000 and LANmark-2000 products have been specially designed to optimize performance with simultaneous operation of voice, data, and power with TEK lab test results proving the benefits of using these products.

While 2.5G and 5.0G commercial equipment is not yet available, the TEK lab has completed modeling of LANmark-1000 and LANmark-2000 products. Based on the test results, Berk-Tek is very confident that LANmark 1000 would be an ideal choice for reliable 2.5G to 100 meters, and LANmark-2000 would provide reliable 5.0G performance to a full 100 meters. However, the installation of Category 6A cabling remains the most logical choice for the future as it will ensure 10Gbps network performance and provide enough bandwidth for 802.11ac wireless and beyond.