High-Density Wireless, It’s Not Just for Arenas Anymore

By Jim Portaro

Arguably we did the first High-Density Wireless for Stock Trading floors at both the New York Stock Exchange (NYSE) and the Chicago Mercantile Exchange (CME). Way back in the mid-Nineties, the NYSE created what was called “The Integrated Technology Plan” to upgrade trading floor networks. From 2001 to 2005, RF-Works COO, Mark Audia and I, were busy designing and deploying the wireless network part of the plan at both the CME and NYSE. It utilized the most sophisticated technology of the time. Handheld terminals, fiber optics, wireless communications and the first large-scale application of high-definition flat-screen technology were installed to speed market information and strengthen trading floor professionals’ ability to manage orders. The initial capacity planned was 1 billion trades. The project called for installing the technology in waves beginning Fridays after the bell and ensuring that the market floor reopened smoothly for trading on Monday mornings.

In recent decades, many beneficial changes have taken place in the Wi-Fi industry. I was on the first 802.11 standards committee; the first specification was 1997 and the first vote passed in 1999. Since then the 802.11 markets have experienced accelerated innovation and now with 802.11ax or WiFi 6 on the horizon, we are seeing wireless transformation in the early adopters thanks to advances in radio technology, the maturation of the smartphone’s and tablets becoming a preferred method of access, and the growing Internet of Things (IoT), which is becoming the Internet of Everything. We are also seeing quicker refreshes of our client’s install base thanks to the benefits of application optimizations and much better hardware and software.

The attention being paid to high density and ultra-high-density planning and design is also growing within the refresh. What needs to be managed is everything including bandwidth. You cannot serve more bandwidth than you have available into the most advanced wireless design. Capitalizing on all of your potential bandwidth is a matter of engineering level planning, proper sizing, and an efficient and highly tuned design.

We are recognized experts on the wireless physical layer and that is where clients routinely see issues. High Client Density is not something most Wi-Fi professionals design around on a daily or even quarterly basis. And as the scale increases, testing the results becomes impractical at least as a lab exercise; we work with our clients on how to get thousands of people to come and sit in your chairs and play with the Wi-Fi, basically put together something on the stage or in the room that interests them.

It’s easier than ever to plan and execute against a High Client Density requirement and deliver a High QoE (Quality of Experience). The key to this is planning, depending on your requirements, it can be a little or a lot. But making choices that support the intended goal and educated guesses about your network is required at some stage. We need to understand how the network will be used to make good technology and resource decisions. And if your requirement details a new service offered on the network, no one really knows how or what the network will ultimately be used for. Fortunately, we have some expertise in this area, and we can offer our experience regarding sizing and expected results as well as design considerations. We are often behind the scenes at new construction, large summits, and network transformation projects. Our best practices have been developed based on experience gathered at multiple small and large venues. The design principles are applicable to any high client density environment. Some of the more common high client density scenarios are boardrooms, auditoriums, meeting rooms, lecture halls, and anyplace that users are likely to gather in large quantities to collaborate. We’ve even done work in a CEO’s estate and a Governor’s mansion.

Understanding the key challenges and learning to design and configure the system to overcome them in a managed fashion, will lead to success. Making Data-Driven decisions is what our best practices are all about. Maximizing the bandwidth per square foot is what RF-Works’ commitment to Wireless Done Right makes not only possible but also makes it manageable and scalable going into the future.


So, if you think you might need High Density or even Ultra High Density, here are 7 general, but critical steps to a successful outcome: 

  1. High-Density Planning,   2. Survey and Design   3. Ensure a Strong Network Foundation,     4. Configuration Considerations,   5. Deploy, Test and Certify 6. Manage Operations and Security,   7. Build Your Roadmap
  1. High-Density Planning:

Together we’ll determine application, services and device requirements such as bandwidth, protocols, frequencies, indoor facilities, outdoor, service level agreements (SLA), etc. We’ll discuss everything from technologies to budgets to total potential bandwidth available. Usually, there is a primary application that is driving the need for high-density connectivity. Understanding the throughput requirements for this application and any other required activities on the network will provide a per-user bandwidth goal. This required per-user bandwidth will be used to drive further design decisions.


  1. Survey and Design

Understanding the requirements for high-density design is the first step and helps ensure a successful design. With so many variables that can affect the RF propagation of an AP and in turn affect the client performance and roaming behaviors, it is always important to have an onsite site survey performed to ensure minimal interference so as to deliver optimal coverage and performance. In addition to verifying the RF propagation in the actual environment, it is also recommended to have a spectrum analysis done as part of the site survey in order to locate any potential sources of RF interference and take steps to remediate them. Site surveys and spectrum analysis should be performed by trained engineers using professional-grade toolkits.

This planning together is the biggest help, but we’ll still plan our work and then work our plan. This will reduce mistakes that cost time and money in the near future. At a minimum, we consider detailed information on expected applications, wireless services, 802.11 a/b/g/n/r/ ac/ax, expected simultaneous and type devices, coverage, cabling constraints, estimates of aggregate throughput per connection density, cell sizing, antennas, and coverage in the design process. There are many other considerations that go into the design from the survey include mounting locations, signal readings, data rates, interference sources, worst necessary clients, directional antennas, and aesthetics.

  1. Ensure a Strong Network Foundation

Be sure the wired network has been refreshed. High-Density Wi-Fi will have a cascading effect down to the network core. The increased bandwidth can saturate the wired edge, and an upgrade there can have a similar impact on the core. Key features required for the wired network are 30-watt power over Ethernet (PoE+), multi-gig interfaces (1/2.5/5 GigE) and 40 GigE uplinks to the core. Also, unified management becomes a must-have. This enables security and access policies to be managed from a single dashboard and propagated across the wired and wireless network simultaneously. It’s important to remember that the wireless experience is only as good as the wired backbone. A highly scalable Software-Defined SD-WAN makes for an agile networking foundation for maximum WiFi interconnectivity and real-time interactivity. The combination of next-gen WiFi, SD-WAN, and IoT work together to achieve the goal of meeting user demands while providing ways a venue can monetize the valuable data captured while providing fans with WiFi access.

  1. Configuration Considerations

Configuration changes can provide a significant improvement in overall throughput by following the High Density best practices for configuring SSIDs, IP assignment, Radio Settings, Client Balancing, bandwidth limits, roaming choices, RX-SOP, speed burst, traffic shaping rules, and many additional options.

Additionally, it is recommended to use RF profiles to better tune the wireless network to support the performance requirements. RF Profiles give you control over band selection, band steering, minimum bitrate, channel selection, channel width and the expected mix of clients usually seen in high-density deployments (such as laptops, mobile phones, and tablets, etc.) the capabilities of clients in such environments also vary.

  1. Deploy, Test and Certify

It’s important to test against all the documentation and review actual against the requirements and assumptions and confirm they are as designed and reasonable. Changing one assumption will significantly impact the number of access points and costs. If you assumed just 1.5 Mbps for HD video chat (as recommended by Microsoft Skype and Cisco Spark) you would need half the number of access points. If you assumed 5 Mbps was required for HD video streaming, you would need more access points. Streaming in your design affects these decisions significantly.

In deployment; precision in mounts, locations, antennas, configuration settings, and a multitude of things make a huge difference. You’d be amazed at the on the fly decision changes that happen from carelessness or a desire to make the task easier. And that’s why we do certifications to ensure compliance to design and to tune differences we see post-deployment.

  1. Manage Operations and Security

It’s one thing to stand up a high density or any enterprise-class wired and wireless network, but we’ll help you also with your monitoring, troubleshooting tools, future capacity planning, best approaches toward optimization, executive dashboarding and reporting based on SLA, Policy, and compliance. Wireless is dynamic, not static so it is critical to have automation tracking your quality of service. An additional area of focus relates to firmware release updates, which you’ll want to be timely in applying. Maybe not the first, but certainly we know that this is an area where hackers focus. Many processes to check when you’re managing licenses, firmware, policy, SLA and especially security in high-density deployments.

A comprehensive wireless security practice includes architecture and vigilant scanning of the RF environment for threats, wireless intrusion, denial of service attacks, and ‘rogue’ access points. We’ll discuss utilizing an integrated wireless intrusion prevention systems (WIPS) to provide these services. Security systems are only as effective as their weakest link, the WLAN must be tailored to the organization’s end-to-end policies and architecture.

Your enterprise or venue may want to utilize identity-based networking and fixed edge instead of a port-based scheme. Identity-based security, though more complex, is far more granular and it applies policies at both the user and device levels. Security can be linked uniquely to the wireless Service Set Identifier (SSID). Remember that configuration errors can open vulnerabilities, an integrated “stateful” firewall in its mobility controller that can identify each user and device as it roams. The result is true identity-based security with pervasive mobility. Since it is assumed that an intruder is constantly monitoring over-the-air traffic in a WLAN, Wi-Fi has evolved with excellent security. Wi-Fi’s WPA2 security framework has yet to be broken and offers considerably greater security than nearly all wired LANs.

  1. Build your Roadmap

It is advised to have ongoing discussions with your technology vendors and service providers semi-annually to build your specific roadmap for your enterprise network. You may want to build or set up a research process or practice, possibly including a steering committee made up of internal and external executives. Our clients who keep up on network trends have the most executive involvement and associated funding. They make sure everyone knows that the network is the access to all of the other IT assets.

There are important trends hitting the market right now like; 802.11ax or Wi-Fi 6 which is loaded with powerful new features, such as Orthogonal Frequency Division Multiple Access (OFDMA), 1024-QAM (quadrature amplitude modulation) encoding and target wake time (TWT), that make Wi-Fi faster and less congested. 802.11ax supports multi-user, multiple-input, multiple-output (MU-MIMO) technology, meaning that a given access point can handle traffic from up to eight users at the same time and at the same speed. Previous-generation APs divided their attention and bandwidth among simultaneous users. These new features will lead to a better mobile experience and longer client battery life, and they will open the door to a wide range of new applications that could not have been done on Wi-Fi before. Wi-Fi 6 is due to be ratified in 2019, but some commercial products are available today. You may consider setting up one “Test” area within your enterprise, let us know.

Nearly every day we see innovations that affect your capacity, coverage, and performance options. Mobile traffic is projected to grow by a factor of 7X, annual roadmap sessions help you plan and budget before you have to solve a problem.


Summary: High-density wireless environments are coming to one of your locations in the near future. Supporting and securing WiFi for hundreds or even thousands of wireless clients in a well-defined area is best served by planning and design. Traditional wireless architectures and best practices simply do not scale well in high-density environments. Expert planning can significantly reduce the cost, complexity, and management of the high-density network while improving overall performance.