Monday, October 1, 2018

Outdoor WiFi is Smaller, Sleeker and Faster #HPE #Aruba #MFD3 #AP387

 Once upon a time, I found myself doing a lot of outdoor WiFi. Not the type of outdoor WiFi you hear people talking about now (stadiums or arenas), but college campuses, outdoor mesh and point to point links.

Recently at Mobility Field Day 3, I ran across this sweet little access point by Aruba. They call it the AP-387. I call it tiny, portable and FAST. It's their new flagship 802.11ac/ad outdoor access point.

They've designed it for maximum distances between APs of 300 meters (that's ~980 feet) and that is just about perfect for most outdoor bridge links. Notice, I said most. We all know of at least one or two bridge links that are pushing a mile long or more. This AP-387 has a 60GHz and a 5GHz radio built into this tiny, outdoor rated package and it is capable of multi-gigabit link speeds. Oh, and it can handle 'rain events' that might make a 5GHz link less than useable.

It has the ability to self-acquire a link by using the electronic scanning capabilities of the 60GHz antenna. It uses existing mounting hardware from the AP-270 (AP-270-MNT-H1/H2). If the link becomes disrupted or block, the radio can scan plus or minus 40 degrees horizontal and plus or minus 10 degrees vertical to re-establish the link. It can even re-engage the link through an RF bounce off of a flat smooth surface (should one exist) between the two ends of the link.

The narrow beam-width of the 60GHz radio lends itself to being co-located within 4-5 meters of another AP-387 using the same 60GHz channel. The AP will power on with the 60GHz radios backed off by 3dB if the AP is getting 802.3af power, which is way better than it not working at all unless it gets 802.3at power. You can see the full product demonstration in this Mobility Field Day 3 video and witness the graceful failover of the link from the 60GHz to the 5GHz radio without dropping the link. Skip to the 15 minute mark to see the link demo.

All of this is bringing me to this point. Doing outdoor mesh/point-to-point site surveys just got that much easier. The AP-387 weighs a fraction of the 17 pound (7.7 kilo) Cisco 1522 I used for my last outdoor survey (circa 2010).

I'll leave you with this video I made to document the insanity of me getting that 87 pound (40 kilo) site survey kit into the back of a Volvo 240 wagon once I'd completed the survey. Times have sure changed in what feels like a short eight years!

Wednesday, September 26, 2018

Meraki's LittleTable Isn't So Little Anymore #MFD3

Way, way back in 2013, I attended Wireless Field Day 4 and I heard a presentation by Sean Rhea of Meraki about their backend database LittleTable, how it was developed, how it worked and how it grew. A few highlights of Sean's presentation covered the server redundancy with data-center redundancy, service provider redundancy and location-redundancy. At that point, the scale per server was a few thousand Meraki devices (switches, wireless Access Points, MXs), hundreds of thousands of clients and hundreds of Gigs of data. The presentation was fascinating to say the least. Recently I had the opportunity to be brought up to date on the status of the Meraki LittleTable database by Jeevan Patil (PM for wireless) and I was a delegate at Mobility Field Day 3 (MFD3).

Meraki has a new (beta) feature in their dashboard called Wireless Health. It is a new feature they enabled in their dashboard that supports all of the Meraki access point models and didn't require their customers to add any additional licensing (or costs) to get this data. Approximately 750,000 networks worldwide now have the ability to see data on poorly performing client devices and access points in a single click. I powered on my older Meraki MR34 access points and added two new MR42 access points to my home (it is a 1928 Florida Faraday cage) and waited for the metrics to trickle into my dashboard.

Now I can see which of my client devices are behaving badly (authentication failures and latency issues). The LittleTable database is so efficient that over 250 billion rows written and one trillion rows queried to the database per day and millions of network devices deployed across 230,000 customers check-in to the dashboard daily. serves 800 million pages to 100 million clients who connect to the dashboard every day. The data in the dashboard is refreshed every second, this makes it extremely useful for troubleshooting. Now I know it is my iOS device is having the worst experience, which makes sense because my apple watch is often left on the charger and not on my wrist. It probably is having a hard time talking to my phone. They're rarely in the same room and my phone rarely has bluetooth enabled.

The Meraki dashboard is amazingly responsive (usually within a second of a click). The responsiveness of the dashboard is pretty amazing considering how many queries are being called every second to the backend database, all across the globe at any given time.

If you want to be brought up to date on what's happening at Meraki, I suggest you check out their video from MFD3 if you haven't already.

Cisco Meraki Mobility Updates from Stephen Foskett on Vimeo.

Tuesday, September 4, 2018

Mobility Field Day 3 Approacheth #MFD3

Mobility Field Day is coming sooon. September 12-14th I will gather with 11 other MFD delegates in San Jose to take part in Mobility Field Day 3! I haven't taken part in a full length Tech Field Day event since Wireless Field Day 8 (and that was a long, long time ago!). A lot has changed since then and I'm looking forward to hearing the latest news from the participating sponsors: Arista, Aruba, Cisco, Fortinet, Mist, Netscout and Nyansa.

Monday, May 7, 2018

Düsseldorf Sights and Sounds 2017

It's been a long time since I've put words down on the Interwebs. Yes, it's true. Last year, David and I were invited to Düsseldorf by 
Düsseldorf Tourismus and Rheinische Post to see Kraftwerk play a concert in their home town and the concert coincided with the Tour de France Grand Depart.

We joined up with a press junket to tour the city, check out some shops, museums and galleries on top of the Kraftwerk concert. The members of the press group were journalists, authors, musicians and press agents. David was set up with press credentials to interview Wolfgang Flur and I was to be working the event as a freelance photographer. As such, I held off on releasing any of my photos to Flickr, Twitter or Instagram until I heard back from the magazine on which photos they wanted to use. Well, the contact I had at the magazine went on radio silence for many months, so I finally put my photos out online, but it really dampened my spirits to get no response to my query and it took me a long time to get reenergized about putting our pictures and video bits together.

I finally finished a video of the collected photos and video snippets we shot while we were in Düsseldorf. Music used in the video comes courtesy of Mike Donaldson via his site!

Tuesday, June 27, 2017

Düsseldorf, Tour De France, Kraftwerk, Air, Friends, Adventure, YES PLEASE!

Photo by @puthoor_photo via Flickr
In just a few hours, David and I will be boarding a plane to Frankfurt & then taking the train to Düsseldorf. Our wild Kraftwerk adventure is leading us to their home town to meet Jan Wiefels who wrote about our wedding in the Rheinische Post! He extended a pair of tickets for us to see Kraftwerk & Air & we booked our travel immediately. Who could say no to an opportunity like this (not us!)?!

Thorsten Schaar reached out to David and I, inviting us to take part in an International Press trip of Kraftwerk and the Grand Depárt (the start of the Tour de France). David is writing an article on the event for Electronic Beats magazine and I'll be their photographer for this story. I can't believe our good fortune. It all began with the pictures I took of David being posted to his Flickr photostream & now my own Flickr account was essential in establishing that I can shoot good pictures every now and then!

Friends of ours will be joining us in Düsseldorf (Marshall, Les, Hilde & our very own Scott Stapleton!) Friday, Saturday and Sunday we'll be with the press group. The members of the International press we're traveling with are authors, musicians, magazine founders, literary agents and sports writers. It's sure to be an interesting group of people.

Many, many photos will be taken. I'm bringing my Polaroid Spectra, Sony a6000 & my trusty Pentax 110 (of course!). My purse/camera bag is heavy with lenses, spare batteries, film and my FauxPro.

Gifts were made with my handy dandy new Cricut machine! So many t-shirts!!!

Thursday, March 30, 2017

A Confluence of Divergent Interests - Interop ITX 2017

I'm inordinately excited to announce that I will be speaking at Interop ITX 2017 and leading two morning yoga classes this year! I couldn't be happier to combine my love of Wi-Fi and yoga at Interop.

You can find me Wednesday May 17th discussing "Wireless Security Gotchas to Avoid" and leading morning yoga classes (poolside) Wednesday and Thursday morning 7am to 8am.

You can save 20% off any Interop pass with the discount code HUBER.

See you soon at Interop at the MGM Grand in Las Vegas!

You can read more about my love of yoga over on my other blog

Comparing the Power Output

Apples & Oranges - They Don't Compare

So many 'news' sources online will compare the UV radiation of an incandescent lightbulb to the radioactive output of plutonium as if the output levels of these two things can even be indicated on the same data chart. The "radiation" power output level of the incandescent bulb is infinitesimally small when compared to legitimately dangerous radioactive particles.

I will attempt to chart the power output of devices often clumped in with one another in comparison conversations with no regard to normalizing the data in order to compare apples to apples. There are differences in spectral density measurements at different operational frequencies and I've calculated these for the common cellular networks (T-Mobile, Verizon and AT&T) based on this Wikipedia entry.

The FCC RF Exposure Guideline document doesn't get into specifics, but gives estimations for typical cellular tower sites. I used my previous blog on Smart Meters and their power output for the links for mW to W calculators, and this Field Strength Calculator tool by Compliance Engineering (a EMC testing laboratory in Australia) just to see if there was any difference in the numbers when represented in V/m
 since Lloyd Burrell of ElectricSense has the opinion that we should use V/instead of W/cm2. I found no difference in the chart data rankings using either numerical representation of the data as you can see in these charted data comparisons. The chart line shape (and the charted difference between the values) is equivalent regardless of which way the data is represented.

This document by the FCC "Questions and Answers about Biological Effects and Potential Hazards of Radiofrequency Electromagnetic Fields" is a bit dated (1999) but shows the mathematical formulas used to derive spectral density metrics for many different types of devices.

I plotted the following devices: Microwaves, Smart Meters, Indoor Wi-Fi Access Points, four common cellular frequencies used today as well as a modern DECT 6.0 cordless phone.

Here is the table version of the data I gathered:

W/cm2 V/m mW/cm2
Microwave 0.0000005 1.37 0.0005
1920–1930 MHz DECT Cordless Phones 0.0000179 8.21 0.0179
Smart Meters 0.000018 8.24 0.018
WiFi Indoor 0.000063 15.41 0.063
100-400MHz 0.0002 27.46 0.2
400MHz 0.0002 27.46 0.2
500MHz 0.00025 30.7 0.25
600MHz 0.0003 33.63 0.3
T-Mobile, Verizon, AT&T 700MHz 0.00035 36.32 0.35
800MHz 0.0004 38.83 0.4
T-Mobile, Verizon, AT&T 850MHz 0.000425 40.03 0.425
900MHz 0.00045 41.19 0.45
1000MHz 0.0005 43.42 0.5
1100MHz 0.00055 45.54 0.55
1200MHz 0.0006 47.56 0.6
1300MHz 0.00065 49.5 0.65
1400MHz 0.0007 51.37 0.7
1500MHz 0.00075 53.17 0.75
1600MHz 0.0008 54.92 0.8
T-Mobile, Verizon, AT&T 1700MHz 0.00085 56.61 0.85
1800MHz 0.0009 58.25 0.9
T-Mobile, Verizon, AT&T 1900MHz 0.00095 59.85 0.95
2000MHz 0.001 61.4 1
FCC Limits Cellular 1.6 2456.01 1600

It is difficult to read the charts when including the FCC limits on cell tower output levels as that value (1.6W/cm2) is nearly 200% higher than the average spectral density measured at cell towers operating in the 1900MHz frequency spectrum (.00095W/cm2). The chart on the left includes the FCC limit and the chart on the right shows the graph of the common "wireless" devices used as comparative items in EMF articles.

I get frustrated when I come across people on the internet claiming to be experts and in the same breath they compare a cordless phone to a microwave to a cell phone agains your head for hours at a time. Just because these things operate "wirelessly" does not mean they all pose the same threat level. This is akin to saying that a house cat is as dangerous as a lion because they're both felines.

You may have noticed that I have not focused on localized exposure to cell phone signals, meaning carrying your cell phone close to your person or having your cell phone next to your head for long periods of time spent talking on the phone. These exposure levels are represented in measures of Specific Absorption Rate (SAR). I am not a mathematician and as such, I've found no way to correlate the power output/spectral density measurements in W/cm2, mW/cm2, V/cm2 to a SAR value. Mobile phones undergo SAR testing in a laboratory environment where the phone is placed near a representation of a human head and SAR absorption rates are measured at different frequencies and positions in which the phone could be held by the user.

The audio quality of the following video is terrible, but the explanation of how SAR testing is performed is quite good.

In the years I've carried a cell phone on my person, the first 6 were only intermittent (only having the cell phone when I was on call) and I'd carry it in my handbag. Since I've had a personal phone, I occasionally carry it in my back pocket, but more often than not - it's in my handbag. When I have long conference calls, I use wired earbuds and sit the phone on my desk. My friend Sam has developed a rash/burn on his upper thigh after many years of carrying his cell phone in his front pants pocket. I do not discredit the potential harm from long term exposure to cell phone signals, but let's not start wearing space blankets! There's a big difference between a psychological ailment and a physiological ailment even if they're both physically debilitating.

If you are curious what the SAR test show for your model of cellphone, you can find this information on the manufacturer's website. Here are links to a few major makes and models.