As wireless deployments continue to keep electrical contractors (ECs) busy, installers are seeing increased diversity in the type and scope of these projects. One reason is the greater reliance on wireless networks. Another is the introduction of the latest wireless standard, 802.11ac. Many companies are still getting good performance out of their 802.11n networks, and others are even chugging along with their older 802.11a/b/g deployments. However, boosted performance and a bevy of new features will surely turn some customers into 802.11ac converts.


Several of the features included in 802.11ac have been on users’ wish lists for quite a while. An increase in channel bandwidth, support for up to eight multiple input, multiple output (MIMO) spatial streams, and multiuser MIMO are just some of the improvements customers will see in the new standard. The first phase (Wave 1) of 802.11ac was ratified at the end of 2013 and is already in the wild. Wave 2, with some follow-on speed and performance improvements, is slated for certification in 2015.


Designing for 802.11ac


Installation of 802.11ac equipment will largely follow conventional wireless network design protocols, but John Anderson, product planner, Fluke Networks Carrier Business Unit, Everett, Wash., believes new projects will typically involve more access points focused on smaller coverage areas. However, the transition to 802.11ac isn’t necessarily the reason for this.


“It’s more due to the increasing density of users in the network,” he said. “What we’re seeing in deployments nowadays, as opposed to a few years ago, is they’re deploying a much denser wireless LAN network.”


More access points are being installed primarily to handle greater numbers of users. However, those additional users also are consuming significantly more bandwidth than they used to, another factor in the design of new wireless deployments.


“It’s also the fact that users are using higher bit-rate applications,” Anderson said.


Most users rely on multiple devices (the tablet has joined the laptop and smartphone for many folks), and bandwidth-intensive platforms, such as video streaming, are all going across those wireless nodes. Remember that, in today’s jargon, “users” of a wireless network doesn’t just mean humans. Wireless sensors also consume resources, so ECs must factor them into network design when organizations deploy them for building automation or other control systems.


Cabling for speed, power


From a cable perspective, there generally are no changes needed to move to 802.11ac, said Dhritiman Dasgupta, senior director of product marketing, Juniper Networks, Sunnyvale, Calif. However, there is a caveat.


“These access points are now handling a lot more traffic and density, so they need more power to operate,” he said. 


He estimated around 80 percent of access points today are powered by power over Ethernet (PoE), and that will likely affect customers and electrical contractors as 2015 approaches.


“Especially for the second wave of 802.11ac access points, you’re looking at close to 30 watts or maybe, in some cases, more than 30W of power,” he said. 


Each vendor’s access points will have their own power requirements.


For customer sites using PoE-­compatible Cat 5 cabling and above, recabling shouldn’t be widely necessary. However, if an EC has customers with hybrid environments that include older Cat 3 cables, they’ll want to begin talking about upgrade options now. If nothing else, it may be prudent for ECs to ensure customers have started the transition to newer switches, which Dasgupta said, are ”capable of delivering more than 30W of power per port without causing a terminal event on the switch or in the wiring closet.”


Along with ensuring there is sufficient power available for the new access points, ECs should also talk with customers about potentially pulling two cables to each access-point location instead of just one. Some of the 802.11ac access points on the market have two RJ-45 ports to support Wave 2 bandwidth. Even if a customer is still installing 802.11n equipment, it would likely be less expensive to run multiple cables for any new access-point locations now than to add cables to existing runs later.


Help customers navigate the upgrade


For sites where a previous standard is already in use, ECs can help ease the transition. Nearly all of the newly released 802.11ac access points and other equipment are backward-compatible to earlier standards. Assuming customers don’t have an urgent business need to reap the rewards of 802.11ac’s faster speeds and other performance enhancements across every connection point, ECs don’t need to worry about ripping out old equipment just yet.


However, there is something to think about when it comes to using previous-generation wireless components. Anderson cautioned that some access-point vendors are recommending enterprises turn off their legacy equipment, “so users won’t connect at those lower rates.” As ECs work with customers to design wireless network expansions and staged replacement projects, maintaining expected performance levels is still important.