Resurrecting an Aerohive, I mean Extreme Networks AP121

You can find some of my original Aerohive AP121 blog posts here. Since then Aerohive has been acquired by Extreme Networks. So I ended up activating an AP230 to the Aerohive HiveManager cloud and was also curious if I could resurrect my old AP121. Low and behold, the AP121 was still supported in HiveManager. I was able to get the AP serial number registered to my new account and added to my HiveManager cloud portal.

The AP121 showed up after a reset by pushing in the physical reset button on the AP for at least 15 seconds while powered on. However, I couldn’t manage the AP121 because the software needed updating according to the devices pane. I tried pushing new firmware from HiveManager but had no success. After digging around the Aerohive support pages and emailing technical support, I found that the AP121 required at minimum software version 6.5r3.

To check the current software version on the AP121, SSH into the access point. The default username should be admin, and the password is aerohive.


#show version

The software version shown was 6.1r6 release build1779, so I had to get to 6.5r3 and load it manually.

I preferred the SCP option, which requires an SCP server. I used my Macbook after I enabled remote login sharing in the OSX sharing preferences.

SSH back into the AP and Run

#save image scp://user@scpserverIPaddress:/directory/AP141-6.5r3.img.S


The AP showed up in HiveManager with the new version 6.5r3. Then I was able to push 6.5.r12 (latest supported software) through the HiveManager cloud portal.

One of my favorite features I found off the bat within HiveManager was the time-lapse feature. Here’s an example of clients moving from my AP230 over to the AP121.

HiveManager client time lapse

I’ve been waiting for a feature like this for years. You’ll be able to watch clients move across different APs in a highly dense wireless deployment. Something I looked for in the past when working in a large Higher Ed environment to determine new AP placement. You could potentially identify sticky client issues easier through this type of visual representation. Quite frankly, every wireless vendor that provides floor maps with APs showing current client statistics should have a time-lapse feature. I’m glad it’s in Aerohive, I mean Extreme Networks.


Attenuation – Friend or Foe

I recently attended a CWNA course taught by none other than Devin Akin, wireless guru and co-founder of CWNP. During the course I was reminded about how attenuation can become your best friend when building high density Wi-Fi networks.

During my time working for a WISP years ago we had a particular site that started to run into problems. This site had a six sector Motorola Canopy setup running on the ISM unlicensed 5Ghz band at the top of a hospital building. The site provided 360 degrees of coverage utilizing six 60 degree sector APs which had worked well for quite some time. These APs utilized a proprietary TDMA radio technology and were also GPS sync’d to allow for efficient channel reuse. However, the AP’s had the potential to hear other non Motorola Canopy GPS sync’d 5Ghz devices from any direction. One day the cluster of AP’s started to pick up numerous interference from other competitive WISP deployments in the area using the same 5Ghz band. Signal to noise ratio dropped and so did CPE performance. We came up with a solution to take each individual sector AP off the tripod at the center of the six story building and mount each of the 60 degree sectors (orange cylinders in picture) below the top edge of the outer building walls. Here’s a simple illustration:

Wireless Access Point Sector move

This new setup allowed the building to provide attenuation from other 5Ghz interference (blue cylinders in picture). After a spectrum analysis was performed on each AP we verified that interference dropped significantly due to the building attenuation. SNR increased and CPE performance increased.

The Motorola Canopy hardware (now Cambium Networks) protocols in use are not using 802.11 protocols, however they use the same unlicensed frequency band and follow the same principles of RF propagation. In high density Wi-Fi deployments attenuation can become your best friend just like the hospital building became ours once we relocated the sector APs. Attenuation such as walls, wall thickness, and number of walls RF propagates through can help reduce co-channel interference between access points AND clients that are reusing the same channel space in high density Wi-Fi deployments.

An easy way we discussed identifying CCI/CCC during the CWNA course was to fire up your favorite wireless tool like Wifi Explorer Pro. Grab a laptop with a similar spec radio that your AP has (ex: your ap is 3×3, use a 3×3 client) and stand right underneath your AP. Here’s what a scan in my house looks like right next to my AP reading a -16 on channel 36.

wifi explorer pro analysis

Identify how many other APs your laptop can hear that are on the same channel of the AP your standing by. In the example above you can see that I can hear another AP using a primary channel of 36 at a -81. This AP along with other nearby clients could have the potential to cause co-channel contention. What you see may not be exactly what the AP hears as every radio has variations in receive sensitivity, but it will help to identify possible contention or interference.

We should no longer build Wi-Fi for maximum distance in enterprise environments like we did years and years ago, but we should now build for capacity and efficiency. So make sure you take advantage of those walls and other building obstacles when designing your next high capacity Wi-Fi network if needed.

Take a look at some of the following references to familiarize yourself with co-channel interference/contention:

If you have any comments or feedback, I’d love to hear from you.


802.11 Wireless Channel Planning

Different Technology

I used to work with Motorola Canopy wireless gear back in the day. It was great ptmp wireless gear. The carrier to interference ratio on this gear was 3 dB, which meant that you could provide extremely reliable wireless links in high RF congested areas. Of course this was proprietary based equipment that didn’t come close to the contention based CDMA/CA 802.11 stuff. I was extremely spoiled when using the Motorola canopy line. It just worked.

802.11 Wireless Channel Planning

Why am I bringing up all this when talking about 802.11 wireless channel planning? Well it’s because of the preconceived notion that using all the 2.4Ghz 802.11 channels may be a good thing (including overlapping channels). At first, I though, just let the AP’s pick the best channel between 1-11 and that I would be good to go. Well that wasn’t the best solution as AP’s were selecting channels 1,3,4,7,10, etc. My thoughts were spurred on by this twitter discussion with wireless guru, Keith Parsons.

Javier S. “What’s better, SNR of 20db between two AP’s on channel 1 or SNR of 20db between AP on channel 1 and AP on channel 3?”
Keith P. “I’d go with the two on the same channel, given a choice. At least they’d ‘Play Nice’ with each other rather than ACI fighting.”
Javier S. “So is it CSMA/CA that works better at detection if interference is on same channel?”

Keith P. “It is the difference between how 802.11 deals with CCI vs ACI.”
Javier S. “So based on CCA, you would rather detect noise and back off rather than face possible data corruption from ACI.?”

The last question wasn’t answered. Basically I needed to do my homework and I would suggest you do the same. Check out the following link:

In the above article Andrew really dives into understanding how CDMA/CA works. What I gathered what that wifi can use carrier sense techniques in order to back off in order to avoid possible frame corruption. Keith’s statement of “AP’s on the same channel will likely play nice with each other” will allow carrier sense to do its job.


Ok, so I started doing some more research which lead me to my safaribooks account and checking out a CWNA (certified wireless network administrator) study guide book. The book defines CCI as co-channel interference or “unnecessary medium contention overhead that occurs because all the AP’s are on the same channel.” (Coleman and Westcott) Basically you have wireless devices following the rules of CDMA/CA.

Now ACI is defined as adjacent channel interference and is what you get when you use channels that overlap with one another. The only non-overlapping channels in 2.4Ghz are 1,6,11. When Keith suggests that he would rather see two AP’s on the same channel instead of two using overlapping channels such as 1 and 3, it’s because the 1 and 3 will give you ACI. ACI will cause re-transmits due to corruption of frames. You will rather want CDMA/CA to work as it should instead of facing re-transmits due to corrupt frames.


Where did this lead me? Well, I turned off the AP’s auto channel feature and went back to only using channels 1, 6, and 11. I hard set the channels myself and performed a site survey. My goal was to try to maximize the SNR between any two AP’s that my client could see that were on the same channel. At the end of the day, I’m seeing better performance especially since we just doubled the number of access points we used to have. I had to also play around with the minimum basic rate and power output levels as well in order to achieve maximum optimization. Hopefully this helps explain why proper channel planning is extremely important.


Here’s a busy, but healthy network using 1,6,11 (Shane, disregard my previous comments on your screenshot using only channels 1, 6, and 11) – Courtesy of Metageek Chanalyzer

Metageek wireless channel planning spectrum image


Healthy 2.4Ghz wireless channel planning. I’m working on 5Ghz as well. – Courtesy of Extreme Networks Oneview.

wireless channel planning 5Ghz building map

Wireless channel planning map

Wireless Channel Planning Resources

CWNA: Certified Wireless Network Administrator Official Study Guide: Exam PW0-105, 3rd Edition by David D. Coleman; David A. Westcott


Raspberry Pi network monitoring wifi Smokeping

I finally deployed my wireless raspberry pi network monitoring device at the edge of our wireless network. I installed the smokeping app on the raspberry pi with wheezy via apt-get. I already had a smokeping running on a Linux server, so I setup the raspberry pi to run smokeping in client mode.

Client mode allows the raspberry pi to pull the config from the smokeping server in order to know what tests to run. I setup some fping, DNS, and tcpping tests. This is a great way to test the client’s wireless experience (latency) on the other side of campus. I stuck the raspberry pi behind a bundle of cables to provide for additional attenuation to simulate a user in a worse case scenario. The AP was a few rooms away on a different floor as well. Here are some of the smokeping graphs:

raspberryPi Smokeping monitoring wifi latency

The line with the higher latency is the raspberry pi to google and the lower line is the latency from the smokeping server to google via fping in the picture above.

Here’s a longer term graph painted vi rrdtool by smokeping. There’s some packet loss going on over the wireless interface on the raspberry pi. I may have to move it to a better spot and see how the graphs look afterward. I also want to install iperf and maybe tshark as well.

RaspberryPi smokeping long term wifi latency

Here’s the command to get the raspberry pi running in client mode:

/usr/sbin/smokeping –master-url= –cache-dir=/var/smokeping/ –shared-secret=/var/smokeping/secret.txt

I also had to modify the permissions in the /tmp/smokeping-ms/data/ folder on the server in order to allow the rrds to be modified by apache.

If you’re looking for a small free solution or larger scale paid solution, take a look at I would recommend giving their NetBeez free tier model a try.


Extreme Networks Wireless AP3705i deployment

I’m working on deploying 96 wireless access points in our student dorm rooms. We originally started with an initial deployment of 40 wireless access points. We installed the original AP’s in the hallways, but had signal issues due to all the HVAC in the vertical walls. Hallway installation wasn’t the greatest idea to begin with, but at the time of the initial installation we had limited funding to run cables to every suite. In our new deployment, we required that contractors pull cables into certain suites. Each suite houses 4 rooms,so I decided to place an AP in every other room and staggered the AP’s from floor to floor. Continue reading »

Meraki Wireless Cloud Managed Dashboard

A few months ago, I was able to acquire a Meraki MR12 AP. I deployed it at a facility that wanted to use airplay between a few iphones and ipads to an appleTV. I figured this would be a great test, as most of the devices would be using bandwidth intense applications. One of the cool features that Meraki has is the ability to detect up to layer 7 applications.

meraki dashboard applications

This graph makes it really easy to see which applications are being used the most. Now you may ask yourself, what can I do with this information, besides create nice graphs and charts for upper management? Well, now that you know what applications are being utilized, you can now create custom policies that can deny or allow certain applications. You can even block certain hostnames or domains. You can also create and apply different bandwidth rate limits based on user or application. Maybe Jonny is trying to stream his favorite you tube video and you have someone else on the same access point who’s trying to do a presentation via airplay. You can decide who gets the highest priority and bandwidth. I like this solution because its an all-in-one setup. You don’t need separate boxes to get the job done. You don’t need a wireless controller or a bandwidth shaper. Now I’m not saying that this is going to work for every solution. Sometimes there is a need for wireless controllers and standalone bandwidth management shapers, but for this type of deployment Meraki fits the bill.

Aerohive HiveManager Maps Tool

The aerohive HiveManager maps feature is pretty powerful. You start off by dropping your wireless access point down on an aerial view map. This allows for exact geocode positioning. You can outline your building with a perimeter in order to get a good floor layout. After you have drawn your perimeter, you can start laying out walls, doors, windows, elevator shafts, and cubicles. Each item represents different amounts of attenuation. To my surprise, the receive signal strength on my wireless devices matched pretty close to the predicted signal strength of the aerohive map. For instance, I was getting a weak signal in the outer N.E. room. I have a brick fireplace that’s in the corner of the room that’s next to the outer N.E. room. I drew that brick wall in the map and now you can see why I have a weak signal back there. The brick fireplace definitively impacts signal strength.



The map feature lets you set the minimum db rate. I have mine set to -80 and the strongest value is -35. You can also change what view you would like to see from the AP. I have mine set to Channel/Power view. You can also change it to hostname, node ID, IP address, or client count. Client count would be nice to see where your AP’s may be saturated with users in a large environment. Overall I’m pretty impressed with the areohive HiveManager maps tool.

Aerohive Wireless Review

I’m finally at a point where I can share my experience with the aerohive AP121 dual radio access point I acquired. When I first received the access point I placed it in my office which is in the northeast corner of my 1600 square foot ranch home. Unfortunately I wasn’t able to test the AP with all of my mobile devices because I wasn’t able to receive a strong enough signal on the other site of the house. I was only picking up at best a receive signal strenght of -78 to -80. This wasn’t good. The connection on my nexus 4, apple first gen IPad, and galaxy S3 would lag and drop connection constantly. I was using a dd-wrt extender AP in my living room which is in the center of my house prior to the aerohive AP. This type of signal penetration is to be expected when you’re working with mobile devices and with an AP that can only pump out a max of 20dbm.

I wanted to get the aerohive AP into the center of the house, so I picked up a pair of netgear powerline 200’s. This worked perfectly. I really wanted to dig into the aerohive cloud based dashboard, “hiveManager” with some client stats and placing the AP in the center of the house allowed all my devices to stay connected without a hitch.

I couldn’t help it. The first place I went to was the spectrum analysis utility.


This is a real-time spectrum analysis using the 2.4 Ghz radio. You get a nice waterfall view as well. The time it takes to refresh is instantaneous and this is going through their online cloud management system over a Comcast connection. I was able to test the speed by firing my dd-wrt repeater up in AP mode on channel 6. I instantly started to see the interference on channel 6. You also can see an FFT duty cycle graph as well, but I left that out on the screen shot.

Here’s another article on the Aerohive Hivemanager maps tool

Meraki Wireless MR12 AP

Here are some pics of the Cisco Meraki MR12.

meraki-2.4Ghz-AP MR12AP

Quick rundown on the MR12 single radio AP spec’s:

1 – 802.11 b/g/n 2×2 mimo radio

1 – 10/100/1000 Ethernet POE plus another 10/100 Ethernet

Internal 3dBi omni-directional antennas

Built in spectrum analyzer to assist with wireless channel planning


Wireless Review

We are currently working on increasing AP density at work in order to keep up with the increasing amount of wireless client devices. It’s always nice to revisit what other product vendors have available, so I was able to get my hands on a few test AP’s.

Aerohive networks AP meraki AP

I will be unboxing and testing these at home. They are lower end AP’s, but this will give me an opportunity at looking into the config user interface, performing some wireless site surveys, and playing with wireless channel planning tools. Stay tuned!

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