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Skip the wireless site survey cost and invest in more wireless APs

A wireless site survey simply provides a one-time snapshot of a work environment's wireless coverage. But Wi-Fi requires ongoing management based on several changing variables.

The first article in this two-part series examined what a wireless site survey is and why it might not contribute much value toward optimizing a wireless LAN installation. In this article, we explore alternatives to the wireless site survey cost and suggest a strategy that will achieve optimal results with lower costs and greater assurance.

Historically, the biggest complaint from end users has been that wireless networks are slow or unavailable, resulting in poor productivity. Therefore, optimizing for wireless coverage alone is a poor strategy -- thus, the wireless site survey is already suspect even before it's started.

The primary way to achieve the capacity that addresses these service issues is to install more access points (APs). By aligning the physical placement of APs with clusters of user demand, you enable the more rapid frequency reuse that maximizes the available radio spectrum.

Wireless APs -- low cost, high capacity

No wireless site survey can determine how to optimize AP density. Instead, review network logs to estimate the locations of demand. You can use data from the continual post-installation monitoring that's found in management consoles and then deploy APs accordingly.

Of course, this data will vary over time and will likely indicate that additional APs are required. IT and network managers should budget about 10% of the total cost of a project for additional APs. Installation costs can be significant, especially if new cabling is required. But the low cost and cost-effectiveness of APs today, along with self-configuration capabilities, result in a better use of scarce IT dollars than the wireless site survey cost.

The financial cost of a formal wireless site survey cannot be justified in many cases.

Thus, the strategy is: Consider where wireless demand will be, deploy devices accordingly, examine the results and fix any problems with additional APs that always add capacity.

Upgrades to newer capacity-enhancing technologies, like 802.11ax, are also an option. These updates could be staged over time as logistics and budgets allow. Additionally, vendors can often push out automatic updates and optimizations for their products.

Wi-Fi systems require ongoing management

You can't always avoid active site surveys in which you walk around an office with a mobile detector to measure the strength of a temporary Wi-Fi AP. While most carpeted, open office environments can skip the survey process, dense manufacturing floors, other industrial settings and buildings with unusual construction might still benefit from a site survey.

The cost of a wireless site survey can buy a lot of APs.

The ongoing monitoring and data gathering, either by APs or dedicated sensors from assurance vendors, is key to success as operating conditions change both quickly and in patterns depending on demand over time.

Recently, I chatted with Anil Gupta, CTO of Wi-Fi assurance vendor Wyebot, based in Marlborough, Mass. He said:

Site surveys can be valuable in some circumstances. But the fundamental and inherent variability in both operating environments and radio frequency performance dictate a continuous, rather than snapshot, strategy for managing any Wi-Fi installation. Attempting to predict performance is nowhere near as valuable as continually monitoring and optimizing the WLAN [wireless LAN] as conditions, including user locations and traffic demands, change both instantaneously and evolve over time.

In other words, invest in tools that provide ongoing optimization, rather than a snapshot attempt at the prediction of performance that probably won't be helpful considering the large number of variables involved.

Emerging technology also a factor

The increasing role of AI and machine learning in automatic problem detection and correction will have a profound effect on future network operations strategies. Managers, for instance, could receive text messages that a new AP is required in a certain location and installation is scheduled for tomorrow morning.

The bottom line: The financial cost of a formal wireless site survey cannot be justified in many cases. Instead, determine loading, locations and trends, and then deploy, monitor and enhance the physical installation as required and as part of equipment upgrades. Emerging tools will automate and reduce the cost of this process even further. You can address gaps in coverage or capacity that appear over time more cost-effectively by adding APs, software-based capabilities and technology upgrades.

In other words, the cost of a wireless site survey can buy a lot of APs.

This was last published in April 2019

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Instead of a wireless site survey, how else would you invest your wireless network dollars?
I appreciate people willing to come at things from a different perspective and challenge established methodologies. However, this exact advice has cost many businesses lots of extra dollars in rework in addition to lost productivity. The fact is that with the current state of WiFi, you can only have so many APs (20ish) broadcasting in the same general area (includes floors above and below) before you exhaust all available spectrum/channels. At that point, adding APs not only doesn't add capacity, it actually lowers it by just increasing overhead while adding nothing beneficial. Because it's such a finite resource, you must strategize and make the most of it. Site Surveys, though not perfect, are simply the best tool we have available with which to do that. 802.11ax will help this. But, we're probably 5 years away from have the device saturation to actually leverage that.
You don't even know what a Wireless Site Survey is! Your description of an Active Site Survey is not correct. What you described was a APoS (AP-on-a-Stick) Survey. Active Site Surveys are when you connect directly to an AP, either temporary OR one that is currently deployed. The link you share on that keyword, to Netscout, doesn't even confirm your description. As a Senior Wireless Network Engineer, I cringed at what you wrote. 
This may be a good strategy in 1 and 2 story stand alone structures but dense areas need surveys to understand the RF environment. Post deployment passive surveys should also be apart of any Wi-Fi deployment costing more then a couple thousand dollars as this represents the only way a customer has to ensure that the wireless system they just paid big for is really truly installed and configured correctly. These IT systems constitute an essential service that businesses can not operate without and only become more dependent upon for success as time goes by. Utilizing a connect and pray mentality is unprofessional and does a disservice to the businesses and people that pay for and depend on them. If you install or sell a wireless system either as a vendor or as an IT department personnel and it preforms poorly due to your neighbors having 20 misconfigured APs that are destroying the RF environment which you were unaware of because you chose not to do things professionally you have failed at your job. Surveys can also help identify security weakness and are part of providing as safe as possible an operating environment. Do not forget that if weakness that are in a system due to poor engineering and understanding are exploited to your customers detriment that they can and will sue for negligence.   
The next time you travel to a hotel I hope they didn't use this strategy cause cutting the walls and ceilings open again to add those extra APs is gonna be more expensive than the survey.