SHARE



ABOUT THE AUTHOR


Greg Wolf
Greg Wolf is a principal with NetForecast, helping to develop and implement performance engineering practices for enterprises. Greg has more...
Read Full Bio >>
SHARE



Greg Wolf | May 22, 2012 |

 
   

RF Interference: When Things Go Bump in the Air

RF Interference: When Things Go Bump in the Air RF interference acts like a light switch. Absent interference, things work fine. However, as soon as interference is present performance comes almost to a grinding halt.

RF interference acts like a light switch. Absent interference, things work fine. However, as soon as interference is present performance comes almost to a grinding halt.

Over the past two months I have attended Enterprise Connect in Orlando and Interop in Las Vegas. Although these conferences typically draw different types of audiences, both conferences had a strong focus on the incredibly fast growth of BYOD in the enterprise. One key to BYOD's success in the enterprise is that it needs access to a well performing Wi-Fi network in order to provide the user access to the enterprise's wired network, so that the user can limit the time connected to (and therefore the charges from) the public cellular network.

The convenient thing about Wi-Fi networks is that they are generally easy to implement. And Wi-Fi networks have a tendency to grow quickly and organically as they are needed. However, like many things, this convenience comes at a price, two to be exact. The first is that Wi-Fi networks operate using a limited amount of spectrum (2.4 GHz and 5 GHz), which tends to grow more crowded and congested as more users take advantage of the BYOD model. The second thing about Wi-Fi networks is that they do not like RF interference--which is the focus of this article.

Simply stated, RF interference is a Wi-Fi network killer! The adverse effect of RF interference is that it causes Wi-Fi performance to suffer, potentially to the point that an application can be rendered unusable.

Network engineers have not had to concern themselves with Layer 1 (physical medium) issues in a very long time but that will need to change. Although RF interference is difficult to eliminate totally, if you can identify the sources of RF interference, many times those sources can be moved or even removed.

RF (radio frequency) interference is generated by any device that operates on the same frequency as the Wi-Fi network. Some common sources of RF interference include Bluetooth, cordless phones, wireless headsets, video cameras, wireless audio devices, and my favorite, the microwave oven. I think it is a safe to say that one or more of these devices exist in most enterprises. Keep in mind that the devices mentioned above typically operate in the 2.4 GHz spectrum, but there are an increasing number of devices that are starting to operate in the 5 GHz spectrum as well.

Another point to mention is that RF interference is not unique to the enterprise. Just take a look around you the next time you are sitting in a Starbucks surfing the web or checking your e-mail using the local Wi-Fi network; I think you would be amazed at how many sources of RF interference are lurking about.

The following diagram shows what happens to Wi-Fi performance when a strong source of RF interference is present. The test consisted of using a laptop on a 2.4 GHz network to download a file from an FTP server. A microwave was turned on twice during the transfer, which resulted in the throughput of the file download almost stopping.

Unlike traditional network performance issues (i.e., latency, jitter, and congestion) that adversely affect application performance, RF interference acts more like a light switch. In the absence of RF interference (light switch off) things work fine. However, as soon as RF interference is present (light switch on) performance comes almost to a grinding halt.

As stated earlier, RF interference is unavoidable. However, network engineers will need to start using tools to help them determine sources of RF interference in their environments and do their best to mitigate the effects of RF interference whenever possible. At a minimum, identifying the presence and sources of RF interference will go a long way when troubleshooting Wi-Fi performance issues.

One of the most valuable tools for detecting RF interference is an RF spectrum analyzer. The one used to conduct the testing for this article is called Chanalyzer Pro (software component) and Wi-Spy DBx (hardware component), which was developed by a company called Metageek. Another excellent set of tools is Wireshark and AirPcap wireless adapters, both owned by Riverbed.

Regardless of what you chose the use, the key is to embrace a set of tools that will give you complete Wi-Fi visibility. Knowing what is floating in the airwaves will pay big dividends as the use of BYOD over Wi-Fi in the enterprise becomes more pervasive.





COMMENTS



Enterprise Connect Orlando 2018
March 12-15 | Orlando, FL

Connect with the Entire Enterprise Communications & Collaboration Ecosystem


Stay Up-to-Date: Hear industry visionaries in Keynotes and General Sessions delivering the latest insight on UC, mobility, collaboration and cloud

Grow Your Network: Connect with the largest gathering of enterprise IT and business leaders and influencers

Learn From Industry Leaders: Attend a full range of Conference Sessions, Free Programs and Special Events

Evaluate All Your Options: Engage with 190+ of the leading equipment, software and service providers

Have Fun! Mingle with sponsors, exhibitors, attendees, guest speakers and industry players during evening receptions

Register now with code NOJITTEREB to save $200 Off Advance Rates or get a FREE Expo Pass!

November 1, 2017

Your customers (internal and external) demand that you offer them the ability to connect by any means. With the adoption of cloud communications tools you now have access to an expanded portfolio o

October 18, 2017

Microsofts recent Ignite event had some critically important announcements for enterprise communications. Namely, Microsofts new Team Collaboration offering, Teams, will be its primary communicatio

September 20, 2017

Customer experience can make or break your business. But how do you achieve outstanding customer service when you're dealing with outdated organizational structure, lagging technology, dated proces

October 23, 2017
Wondering which Office 365 collaboration tool to use when? Get quick pointers from CBT Nuggets instructor Simona Millham.
September 22, 2017
In this podcast, we explore the future of work with Robert Brown, AVP of the Cognizant Center for the Future of Work, who helps us answer the question, "What do we do when machines do everything?"
September 8, 2017
Greg Collins, a technology analyst and strategist with Exact Ventures, delivers a status report on 5G implementation plans and tells enterprises why they shouldn't wait to move ahead on potential use ....
August 25, 2017
Find out what business considerations are driving the SIP trunking market today, and learn a bit about how satisfied enterprises are with their providers. We talk with John Malone, president of The Ea....
August 16, 2017
World Vision U.S. is finding lots of goodness in RingCentral's cloud communications service, but as Randy Boyd, infrastructure architect at the global humanitarian nonprofit, tells us, he and his team....
August 11, 2017
Alicia Gee, director of unified communications at Sutter Physician Services, oversees the technical team supporting a 1,000-agent contact center running on Genesys PureConnect. She catches us up on th....
August 4, 2017
Andrew Prokop, communications evangelist with Arrow Systems Integration, has lately been working on integrating enterprise communications into Internet of Things ecosystems. He shares examples and off....
July 27, 2017
Industry watcher Elka Popova, a Frost & Sullivan program director, shares her perspective on this acquisition, discussing Mitel's market positioning, why the move makes sense, and more.
July 14, 2017
Lantre Barr, founder and CEO of Blacc Spot Media, urges any enterprise that's been on the fence about integrating real-time communications into business workflows to jump off and get started. Tune and....
June 28, 2017
Communications expert Tsahi Levent-Levi, author of the popular BlogGeek.me blog, keeps a running tally and comprehensive overview of communications platform-as-a-service offerings in his "Choosing a W....
June 9, 2017
If you think telecom expense management applies to nothing more than business phone lines, think again. Hyoun Park, founder and principal investigator with technology advisory Amalgam Insights, tells ....
June 2, 2017
Enterprises strategizing on mobility today, including for internal collaboration, don't have the luxury of learning as they go. Tony Rizzo, enterprise mobility specialist with Blue Hill Research, expl....
May 24, 2017
Mark Winther, head of IDC's global telecom consulting practice, gives us his take on how CPaaS providers evolve beyond the basic building blocks and address maturing enterprise needs.
May 18, 2017
Diane Myers, senior research director at IHS Markit, walks us through her 2017 UC-as-a-service report... and shares what might be to come in 2018.
April 28, 2017
Change isn't easy, but it is necessary. Tune in for advice and perspective from Zeus Kerravala, co-author of a "Digital Transformation for Dummies" special edition.
April 20, 2017
Robin Gareiss, president of Nemertes Research, shares insight gleaned from the firm's 12th annual UCC Total Cost of Operations study.
March 23, 2017
Tim Banting, of Current Analysis, gives us a peek into what the next three years will bring in advance of his Enterprise Connect session exploring the question: Will there be a new model for enterpris....
March 15, 2017
Andrew Prokop, communications evangelist with Arrow Systems Integration, discusses the evolving role of the all-important session border controller.
March 9, 2017
Organizer Alan Quayle gives us the lowdown on programmable communications and all you need to know about participating in this pre-Enterprise Connect hackathon.
March 3, 2017
From protecting against new vulnerabilities to keeping security assessments up to date, security consultant Mark Collier shares tips on how best to protect your UC systems.
February 24, 2017
UC analyst Blair Pleasant sorts through the myriad cloud architectural models underlying UCaaS and CCaaS offerings, and explains why knowing the differences matter.
February 17, 2017
From the most basics of basics to the hidden gotchas, UC consultant Melissa Swartz helps demystify the complex world of SIP trunking.
February 7, 2017
UC&C consultant Kevin Kieller, a partner at enableUC, shares pointers for making the right architectural choices for your Skype for Business deployment.
February 1, 2017
Elka Popova, a Frost & Sullivan program director, shares a status report on the UCaaS market today and offers her perspective on what large enterprises need before committing to UC in the cloud.
January 26, 2017
Andrew Davis, co-founder of Wainhouse Research and chair of the Video track at Enterprise Connect 2017, sorts through the myriad cloud video service options and shares how to tell if your choice is en....
January 23, 2017
Sheila McGee-Smith, Contact Center/Customer Experience track chair for Enterprise Connect 2017, tells us what we need to know about the role cloud software is playing in contact centers today.