About subnetwork

Jonathan Davis loves network engineering. He's been in IT for over 17 years. In that time, he has worked in almost every aspect of IT. Nothing holds his attention and imagination like building wireless networks for unique environments.

Geek Tools – Cape Networks for Wireless Monitoring

“Wireless isn’t working!” – everyone

How many times have we heard that mantra? As wireless engineers we know all of the intricate details that are required to be in place before wireless “just works.” We often find ourselves trying to explain this to people who see wireless as magic, and us as the magicians. They don’t care about the intricacies of roaming. They don’t care about the underlying systems, many of which we rarely control. DHCP, DNS, RADIUS, and ultimately the services they are trying to connect to.

Assuming a medium to large sized corporate environment, there is likely someone (a team) responsible for the DNS, DHCP, and Radius, and that is not likely to be the same team responsible for wireless. In very large environments, the LAN team that even provides the network cable for the AP may be a different team.

Further increasing the confusion is that problems can often appear isolated, with only a small group of users experiencing the issue.

Then the troubleshooting must begin. Is it a client issue? Were drivers or firmware recently updated on the users systems? Is there a common location, time, or AP that the experience is related to? The list of questions begin to build.

I ran into this in my own network recently. Users were complaining of being unable to connect to wireless. The problems were reported from various locations slowly over a number of days. No particular client was having consistent issues, and I never saw the problem on a customers computer while they were having it. I began looking through logs and following pretty standard troubleshooting steps. Nothing came up. It was as if the problem didn’t exist, yet I was hearing about it often enough to believe that it did.

Considering that I had just returned from Mobility Field Day 2 and participated in the Cape Networks session, I had an idea. Cape Networks provided delegates with a sensor to test. I spoke with my manager at work, a very smart guy (he hired me, right?) who agreed it would be OK to test the sensor in our environment.

The secret to the Cape Networks sensor is that it IS a client. It sees what a client experiences and its entire function is to report on the user experience. It is cloud connected, with an intuitive dashboard, that makes setup and management easy, and remote troubleshooting painless. You really should watch the Cape Networks presentation!

After installing the sensor and configuring the device for our wireless network and the internal services that I wanted it to test, I walked away and forgot about it for a day.
The next morning, I logged back in, and my issue was staring me in the face. DHCP

The time to get a DHCP address was all over the map, peaking as high as 11 seconds. Problem found! Users who experienced those peaks would clearly have issues connecting; add in their own impatience, maybe turning off and on wireless, and of course they couldn’t connect.

Before and after changes were implemented to resolve the DHCP issues users experienced.

Before and after changes were made to DHCP.

What was even more important was that I now had clear metrics that I could take to my team that manages DHCP. I could point to the problem, and then after we developed and implemented a resolution, I was able to point to the same metrics as proof that our plan worked.

As you might have guessed, complaints and rumors of complaints quickly died away.

My organization has since made the decision to invest in sensors from Cape Networks. Their reporting and ease of use make for an unmistakable value. I strongly recommend that you also check them out.

As a MFD2 delegate, I did receive a free sensor from Cape Networks and various stickers and other low value (but tasty) snacks. All other expenses for MFD were covered by Tech Field Day. I was not compelled to write about Cape Networks in any way other than personal user experience. My employers decision to purchase sensors was based solely on the user experience and ease of problem resolution.

Looking ahead to Mobility Field Day 2

This week I am attending Mobility Field Day 2, taking place in San Jose, CA! This is my seventh event with Tech Field Day and I am excited for what the week has to offer.
As an attendee at Network Field Day 8 and 9, the focus in networking was towards Datacenter and WAN. During that same time, my personal career was arcing towards wireless. I was reading, thinking, and practicing a lot of wireless for a major global manufacturing company. I left from those events feeling amazed at all that was happening within the realm of networking, but also feeling like an imposter.
I wasn’t worrying much about SDN WAN, I was too focused on designing and deploying high density wireless in a manufacturing space. I wasn’t thinking about data center, but I was instead providing coverage to warehouses in the million+ sq/ft range.
A lot has happened in my career since those events, and I have made myself at home in the realm of wireless. I continue to learn and grow as a wireless engineer, and Mobility Field Day is another step in my development. More importantly, I’m at an event that speaks to my passion. Tech Field Day events are always incredibly informative, but this one just resonates!
We have some great presenters this week, including Cape Networks, Mist Systems, Mojo NetworksNetscout, and Nyansa.
Aside from the presenters, Mobility Field Day 2 has some awesome delegates, many of whom I consider friends. The opportunity to exchange ideas, ask questions, and participate with them is very exciting.
Speaking of participation, my absolute favorite part of Mobility Field Day is that everyone can participate. Nearly all of the sessions are live streamed. You can watch with us live, send tweets or DM’s, and be part of the event yourself.
Please feel free to send me your questions on Twitter. I will be happy to ask them as time allows and you too can participate in what looks to be another great Tech Field Day event!

Kilted Monday 2017

Kilted Monday is nearly here!

We have a couple of planned activities, and there are always a few surprises. Here’s what you know to make the day a success.CnIB_vQVMAA3wcO

When you step out of the hotel on Monday, you’re gonna feel strange! I get it. Who wears a kilt to a professional conference, right? You do, that’s who!

Hold that head up high, and go directly to the Social Media Lounge! The kilts normally gather there, and you’ll immediately feel better once you are surrounded by your peers!

Throughout the day, check the #KiltedMonday hash-tag on Twitter. There, you will find where the kilts are gathering during the breaks, funny pictures, special giveaways in the World of Solutions (yes, that does happen), and any additional info needed to make your day a success.

Finally, check back here. I will update as the day progresses if there are any last minute events or things you should know.

There are two events scheduled!

Kilts vs. Kiltless Racing!

WHEN: Gather at 1:00pm, Racing begins at 1:30pm *UPDATED TO NEW TIME*
WHERE: Kinetic Tiles in the World of Solutions Foyer
We know that kilts are cool! But, did you know that they make you run faster? We’re going to prove that to the poor people who forgot to wear their kilts! Even if you don’t feel like running, show up to support the kilts who do race.

Kilted Monday Meetup and Pictures

WHEN: 6:00pm
WHERE: Social Media Lounge (Confirmed)
This is an opportunity to meet everyone who made Kilted Monday the incredible event that it has become. We will take lots of pictures and tell funny stories from the day.

I hope you are ready for an awesome experience! I know that I am.

Cisco Live 2017 – Kilted Monday, Healthy Feet, and LOTS of water!

Cisco Live 2017 is just around the corner, and I am already thinking about my packing list. Here are a few things that you might want to pack as well.

CnIB_vQVMAA3wcO

Picture by @Renegade604

Your Kilt! Yes, you knew it would make the top of the list. #KiltedMonday has grown from three guys making a joke to one of the most awesome events at ANY tech conference. Last year’s #KiltedMonday included a competition for best legs as well as special gifts for participants in the World of Solutions! If you haven’t purchased a kilt yet, there is still time! Get it now so that you can be part of the cool (and breezy) crowd! On Monday, be certain to follow #KiltedMonday on Twitter to keep up with everything that is going on.

A water bottle. Cisco Live does an awesome job of providing water coolers for participants nearly everywhere you will go for the conference. That often ends when you get back to your hotel, and when you add in the extreme heat and dry air of Las Vegas, along with the occasional alcoholic beverage, you will need LOTS of water. Don’t make the mistake I did. Last year, I forgot to fill my water bottle before heading back to my hotel room. The closest bottle of water I could buy was $8! That’s right, $8 for a 32oz bottle of water.

Moleskin. At Cisco Live you will walk a lot! It really doesn’t matter how well your shoes are broken in, your feet will begin to find the rough spots and moleskin will make the difference between a miserable day and comfort. Before you pack the moleskin, go ahead and cut it into squares, and then toss the squares into a tin or ziplock bag. This way, you will ensure that you have it with you when you need it, and take my word on this, moleskin doesn’t tear easily.

A good attitude. Be ready to learn! Not only from the instructors and speakers but from each other. There is an incredible brain trust that attends Cisco Live!

I am certainly looking forward to Cisco Live, and I hope you are too! I will see you in Vegas!

Geek Tools – Installing Spectools on WLPC Odroid

spectoolsscreenOne of the maker sessions from WLPC was setting up an Odroid for use as a network tool. It was a great session and I hope to see more of these at future WLPC’s. Once the videos are posted, you will be able to find the link here.

The first thing I wanted to try was installing Spectools on my Odroid to use with my Metageek Spectrum Analyzers. I have two Metageek Wi-Spy DBx’s and thanks to the 2017 WLPC bag, one Wi-Spy 2.4x.

The Wi-Spy 2.4x analyzer is supported in a much older version of Spectools. If you only own that one analyzer, simply run the following from the CLI:

sudo apt-get install spectools

On the other hand, if you want to use Spectools with a DBx, you must compile from the latest version. This takes a bit more work as it must be compiled from the source code. After fumbling around with it along with Jerry Olla we were both able to get it successfully installed and working.

Here are the directions which worked for both Jerry and I.

  1. Install the required prereqs:
sudo apt-get install libgtk2.0-dev libusb-dev build-essential

2. Clone the Spectools package:

git clone https://www.kismetwireless.net/spectools.git

3. Change to the Spectools directory:

cd spectools

4. Now, the fun part. The included config.guess will not recognize the Odroid. However, the distribution installed on the Odroid includes a MUCH newer version that will, so we need to copy it to the spectools directory:

cp /usr/share/misc/config.guess config.guess

5. Now we can follow the standard process to compile Spectools to operate on the Odroid.

./configure
make
make install

And with that, Spectools should now support the Metageek dbx. Install VNC, and you have an easily deployable sensor.

Up next, installing Websockets for wi-spy

An open letter to Senator Richard Burr

I sent this to Senator Richard Burr through his website. I am also leaving it here, and will update with his response:

Senator Burr,

First, I want to say Thank You for working on the behalf of North Carolina in our nation’s capital. I recognize that there are hundreds, if not thousands of issues that you are asked to consider on a regular basis, which cannot be easy.

I am contacting you regarding the encryption bill that you are working on with Senator Feinstein. North Carolina is a very tech savvy state. We have major technology companies in almost every tech sector, and now are home to some of the largest and most efficient data centers in the US. There is much to be proud of. With that in mind, I am surprised to see you as one of the advocates of the bill.

I recognize that as the Chair of the Senate Intelligence Committee you hear from our intelligence services on a regular basis. I am certain the current conversation is heavily geared towards how to deal with the pervasive nature of encryption. Today it is easy for a terrorist organization to have fully encrypted end-to-end communication. I am sure that is incredibly frightening to the intelligence services and their job is a very difficult one. I recognize that every attack on American citizens ultimately creates hundreds of questions like “How did the [insert three letter acronym] not know this was going to happen?” It’s an impossible battle.

I am a network engineer and I have worked in IT for many years. I intimately understand encryption and the basic underpinnings of the internet. I have spent many years protecting my employers networks and systems from outside attack. I understand that ever evolving battle first-hand.

With that said, I am very concerned that you feel that you can force companies to provide backdoor access to devices and communication without affecting every citizen who chooses to use an electronic device. I assume that you have chosen to believe the rhetoric which states that open access can be protected. Otherwise, the only other assumption is that you believe that normal everyday citizens should not have the ability to protect their private, personal information; that corporations should not have the ability to protect their intellectual property.

Assuming that you believe the former; I want you to consider these questions. How long do you expect that backdoor to be kept safe? How long do you think it will take before technical terrorist, both foreign and domestic find and utilize that backdoor?

If the US makes and is granted the demand, what prevents other foreign entities from doing the same? What do you think the economic impact would be for companies when China has a backdoor to every corporate device of every manufacturing company in the US? I have spent eight years of my career working with large international manufacturing companies. I know first hand what the impact of that is. I have watched it with my own eyes. I could argue this particular point, citing experience, but I want to respect your time. If you would like to discuss, I will be happy to do so.

I have one more question I would like to present. How do you expect that forcing backdoor access will actually aid the intelligence services? This is an exercise in futility and escalation. Assume for a moment that the NSA/CIA/FBI has root access to every device. What happens when the user also employs an encrypted communication app which also requires a passcode and does not store data locally? Let’s also suppose that they are always running a VPN or TOR client. Finally, let’s assume that the server the encrypted app on the encrypted phone, communicates to through an encrypted tunnel, lives in a non-friendly foreign state. What good does this legislation then do? The answer is, none. The US cannot compel the foreign server to give it a back door. But, the US, who loves to discuss freedom has created a wide exploit that will then begin to be used for a different type of terrorism and removed every citizens right to privacy with their most personal data.

I am not hurling these questions at a wall to see what sticks. I would like a response. This is a very important discussion to be had without rhetoric and fear-mongering. I can be contacted with the information provided if you would like to further discuss these or other concerns.

With respect,

Jonathan Davis

Cisco Live 2016 is coming and so are the kilts

Forget winter, Cisco Live 2016 is coming, and it is going to be hot! No, I’m not referring to the fact that it is taking place in Las Vegas, NV during July. I am referring to #KiltedMonday.

“What is #KiltedMonday“, you ask? Simple, it’s when people wear kilts to Cisco Live.

“Why would people wear kilts to Cisco Live”, you ask? Because we will be in Las Vegas in July. Kilts are breezy.

kiltedmonday

Yes, people actually wear kilts to Cisco Live.

No really, Kilted Monday started as a joke on Twitter last year between myself@ucgod, and @wifijanitor. That joke blossomed and bloomed until @CiscoLive picked it up and put us on the Photo Scavenger Hunt.

Now, it seems the joke has grown legs. (See what I did there?)

@DeniseFishburn has ordered her kilt, and @amyengineer and @ScottMorrisCCIE are joining us. Let’s face it…if Denise is doing it, you know it will be fun.

This is your official invite to be part of the cool (and breezy) crowd. 

So, you want to join in, but sadly have found yourself kilt-less. No worries, I ordered mine from damnnearkiltem.com. I like my kilt, they are well priced, and have great shipping. Plus, with a name like that, how can you resist? (No, I don’t get a commission)

I will suggest that you must! measure yourself per their directions. I had to exchange the first kilt I ordered. Your pants size is not your kilt size.

Also, if you haven’t  already registered, now is a great time to get registered for Cisco Live US 2016. It’s going to be another great year!