
Products that adhere to the latest WiFi standard, 802.11ac, have now been shipping for a year and are being adopted at a healthy rate. If you will soon be among the adopters, we offer these considerations as you map your wireless LAN strategy.
First, the numbers. In its latest Worldwide Quarterly WLAN Tracker report, released in September, IDC says the enterprise WLAN market grew 7.7% over the same quarter last year, thanks in part to healthy 802.11ac sales, driven by competitive pricing and capacity and throughput:
The transition from the 802.11n standard to the newer and faster 802.11ac standard is progressing rapidly and above expectations in the enterprise segment. After just four quarters of product availability, the 802.11ac standard already accounts for 19% of dependent access point shipments and 30% of dependent access point revenues, a noticeably faster adoption rate than what the market experienced with the 802.11a/b/g to 802.11n transition several years ago. The primary reasons behind this trend lies with aggressive pricing for the 802.11ac access points adopted by most vendors with minimal or no price premium over the 802.11n products and to the inherent benefits of 802.11ac products in high density environments.
Gigabit WLAN is UC-ready
The “inherent benefits” to which IDC refers come mostly in the speed department, as the 802.11ac spec supports speeds of 1.3G bps. That’s typically enough to handle even the most demanding mix of voice, video and data throughout a building or campus.
Consider West Chester University in Pennsylvania, which recently went all wireless in the 12 residence halls and student apartments that house some 5,000 students. It’s hard to think of a population that can stress a wireless network more so than 5,000 college kids. As Richard Chan, Assistant Director, Networking and Telecommunications for West Chester University, explains:
“Our students were really relying on wireless connectivity not just for basic Internet and email access for course work, but also for access to online courses and distance learning, plus social media and HD video streaming. We realized the right approach was to equip all of the existing dorms with ultra-fast Wi-Fi and ensure that all of the new dorms were all-wireless from the ground up.”
The university installed Aruba’s 802.11ac AP-220 Series access points for both indoor and outdoor coverage of the student housing areas. Chan says the decision was an easy one from a cost perspective:
“By eliminating cabling costs and going all-wireless in some of the buildings, we’ve been able to realize over $1 million in total cost savings. That made cutting the cord a simple choice.”
Considerations for 802.11ac Deployments
Such savings are hard to ignore, but as with any network infrastructure project, there’s no shortage of considerations when deploying new 802.11ac WiFi gear.
First is whether to add new 802.11ac equipment to your existing network or replace all of your access points with new gear. The first option, referred to as an “overlay” network, is probably the better bet if most of your clients still use the 802.11n or older WLAN technology, which operates in the 2.4GHZ band. As Network World reports:
Since 802.11ac only uses the 5GHz band, there will be little or no disruption to your current user base, and new clients with 802.11ac technology will immediately benefit from the new network. And, if you have clients that already support 802.11ac technologies (like the newer Macbooks) you will even see a benefit on your existing 2.4GHz network as these users will seamlessly migrate to the new 802.11ac network, freeing up bandwidth on the 2.4GHz channels.
If you go the rip-and-replace route, you’ll still have support for older clients because most 802.11ac APs have dual radios, with one supporting the legacy 2.4GHz band. The Network World story explains the advantage and drawback:
You’ll end up with a simpler and easier to manage WLAN infrastructure. But a rip-and-replace strategy is typically more expensive, as you’ll need new APs everywhere, not just in the areas where you need higher capacity today.
Before making that decision, it’s a good idea to assess how many 802.11ac-capable clients you’ve got, says Gary Newbold, Vice President, Asia Pacific and Japan for Extreme Networks:
This is probably the most overlooked aspect of wireless networking. A faster access point will not be of any use unless an organization has the capability to support it. So organizations should consider their environment to ensure expectations are aligned and required speeds achieved.
At the same time, it’s a good idea to conduct a site survey to ensure you have appropriate coverage and to determine the best spots to place APs. As the Network World story explains:
With 802.11ac you’re entering some unchartered territory: the 5GHz band. A professional site survey will tell you exactly what the 5GHz band looks like in your environment, helping you identify and avoid existing interferers, and make smart configuration choices for your new equipment.
Better off Waiting for 802.11ac Wave 2?
At the risk of raining on this 802.11ac parade, there’s also some chatter that it may be best to wait for the next round of 802.11ac equipment, the so-called Wave 2.
As with most standards, vendors started delivering 802.11ac equipment before the specification was fully buffed and polished. The WiFi Alliance, which certifies equipment for standards compliance, gave some of that early equipment its blessing. As Andrew Myles, manager of enterprise standards at Cisco, told itnews.com:
“The Wi-Fi Alliance decided to ratify a draft version of the 802.11ac amendment. That became Wave 1 and now the Alliance has a project to take additional features from the standard and certify against them.
“We don’t know what will be in Wave 2 and I would not expect a certification coming from the Wi-Fi Alliance for quite a long time. If it was over a year, I would not be surprised.”
You’ll have to decide if your environment can wait that long, or if you’re willing to deal with any differences between the two waves.