Evolution of Wireless: Understanding 802.11ac and Why it Means MORE Cabling in Enterprise Networks

Networks using IEEE 802.11ac technology will prepare the enterprise for more wireless devices, more access points, and faster speeds in the workplace, but users won't see the true benefits of the new standard without the right cabling infrastructure in place to support it.

Wireless networks are now ubiquitous in the workplace, and a growing number of companies are adopting Bring Your Own Device (BYOD) policies. These policies aren't just covering smartphones: A 2013 Forrester Survey of 35,000 IT managers found an increasing number of BYOD tablets and PCs gaining acceptance. The vast majority of these devices will rely on wireless networks. It's no surprise that in just two years wireless data traffic will likely exceed wired circuit traffic.

All these devices in the workplace can quickly tax a wireless network. But with the help of recent standards from IEEE and TIA, along with important backbone cabling upgrades, wireless access points will be able to handle more traffic and deliver data faster now and in the future.

Enter 802.11ac
802.11ac defines the next generation of Wi-Fi, and succeeds 802.11n. While 802.11ac was approved in late 2013, 802.11ac-enabled smartphones, routers, and laptops have been on the market since 2012. Many people are already using phones and laptops capable of connecting at the higher speed and frequencies 802.11ac offers. In fact, 802.11ac devices are expected to represent 45 percent of consumer Wi-Fi equipment by the end of this year, according to ABI Research.

802.11ac offers several major improvements over the previous 802.11n standard:

1. Capacity to Support More Users
Early 802.11 networks used a single antenna and one data stream. 802.11n made improvements by supporting up to three antennas and three streams simultaneously using technology called multiple-input multiple-output (MIMO). 802.11ac goes a step further by allowing Multi User multiple-input multiple-output (MU-MIMO) as it has the capacity to transmit and receive from multiple users at the same time.

Also, 802.11ac is working over a 5 GHz spectrum band. This frequency offers five times the capacity of 2.4 GHz, the frequency for 802.11n. And 802.11ac is dual-band, so it will support 5 GHz and also be backwards compatible with products that operate at 2.4 GHz.

2. Better Link Reliability
As a result of using multiple antennas with MIMO technology, 802.11ac can take advantage of beamforming, a technique that transmits a concentrated signal directly to devices instead of broadcasting the signal out to a wide area. Beamforming not only improves bandwidth utilization, it can increase the range of the wireless network.

3. Faster Data Rates
802.11ac allows for a possible 8 spatial streams for parallel data transfers, at 80 MHz per channel. This translates into up to a 1.3 Gbps per radio data rate capability for first generation technology. This goes well beyond 802.11n, which defined up to 4 spatial streams for parallel data transfers and 40 MHz wide channels for data rates up to 450 Mbps. Future generations of 802.11ac products will allow for 160 MHz channel bandwidth for 2.6 Gbps, and eventually up to 6.7 Gbps.

Key Recommendations for Cabling Infrastructure
Enterprise wireless access points (WAPs) and backbone cabling infrastructure will need to be upgraded to see the real benefits of 802.11ac, and standards have been revised to support access point upgrades. In late 2013, TIA published TSB-162-A, Telecommunications Cabling Guidelines for Wireless Access Points, which revises recommendations for mounting and routing cable between LAN equipment and WAPs.

This update specifies installing twisted-pair Cat 6A or OM3 fiber (or better) for horizontal cabling to WAPs. These high bandwidth solutions can prepare wireless networks for the next waves of 802.11ac devices, as data rates grow from 433kb/s to 1.3 Gbps and potentially 7 Gbps. By using a Cat 6A RJ-45 interface and twisted-pair structured cabling system, users get the added benefit of backwards compatibility and connection from the horizontal cabling all the way to the backbone and active gear.

TSB-162-A also recommends using grid-based zone cabling architectures, with each cell in the grid no greater than 60 feet (18.3 meters) wide. Many designs will likely use smaller grid cells - and in turn require additional WAPs - to improve data rates and allow for greater occupancy rates in each cell.

At least two Cat 6A cable runs are recommended to each cell in the grid architecture. As 802.11ac WAPs allow for Power over Ethernet (PoE), it is recommended to run two Cat 6A cables to each WAP for backup power capabilities in case one power source isn't working. Leviton also suggests installing shielded cabling for PoE applications, as it reduces heat buildup in cable bundles.

What's Next
In March 2014, IEEE approved a task force to create 802.11ax, a follow-up to 802.11ac which will improve Gigabit-speed connections to devices and offer greater network capacity. The standard is expected to be complete by mid 2018, but, as with 802.11ac, devices that support the draft standard will arrive much sooner, likely as soon as 2016.

Businesses who upgrade their backbone cabling infrastructure today with Cat 6A cabling based on TSB-162-A recommendations will not only prepare their workplaces for 802.11ac, but will be ready for 802.11ax-enabled devices in the near future.