Is My WLAN Controller Healthy (or, how do I program my stereo’s equalizer)?

old-stereo

When I was young, maybe early teens, I remember having a friend who’s dad was super proud of his stereo system.  I remember it had a stereophonic hifi turntable, 2 cassette decks (for dubbing), and it was even hooked to his reel-to-reel. I remember thinking of how powerful it was… I mean, LOOK at all those buttons, knobs, and sliders!  We got in trouble once because we messed with the equalizer.  He had just recently got it sounding like he wanted it and we… well… undid his work.

Now later in life I learned that just about no one knew how to properly set an equalizer, and this included my friend’s dad (nor did he know it should be tuned for each type of music).  He just did the best he could, trying to decipher the instructions, and taking best guesses.  Take this equalizer in the picture… it has 10 sliders from 31 Hz (sub bass) on the left to 16 Khz (high tones) on the right.  Now this picture will do nothing but make a muddy mix, the highs and mids louder and pulling down the low-mid sounds… so yeah… but that’s not the point. (But if you want a good reference for setting your EQ check this out.)

My point is there are a lot of buttons, knobs, and sliders, and they all work together.  For some of them, if they’re just a little off, it could change the sound in a major way.  Just like on an enterprise class wireless system.  Am I right?

So now then how do I configure my equalizer Cisco Wireless LAN Controller?  Great question.  Glad you asked.

When I log on to a controller I want to first see if it’s healthy.  Go through each row of the table below to see what I tend to look for in determining health.  This is not an exhaustive list, but it’s a solid start.  If your WLAN is “healthy” based on this list and you’re still having trouble, then we’d start troubleshooting.

(Please note that as I begin to use this as a reference I may find ways to make it better.  Be sure to check back later for updates.  Use the comment section below if you have ideas, too.)

What I’m Looking For Resources
Monitor Top Tab
What version of code is the controller running? I like to see the controller running the latest MD release for whatever code train it’s running. This is often referred to as a Maintenance Release or MR.

Be sure to check release notes before upgrading code, noting support for the equipment that is deployed.

There are (typically) no reasons to use any code earlier than 7.6 in a production environment.

What is the uptime? Is there a reasonable explanation for when it last rebooted?  It should never reboot on it’s own.
Are any 2.4 or 5 GHz radios listed as Down and you’re not sure why? Since there are only 3 usable channels in 2.4 GHz and 12-20+ in 5 GHz it’s not uncommon to see some 2.4 GHz radios turned off so AP’s can be packed in tighter to accommodate a lot of clients.
Do you have any Excluded or Disabled Clients? It is recommended to keep the client exclusion policies turned on. Clients can be excluded for:

Excessive 802.11 Association or Authentication failures

Excessive 802.1x Authentication failures

Duplicate IP (referenced as Identity Theft or IP Reuse)

Excessive Web Authentication failures

Any disabled clients were done manually.

Is there an excessive amount of Active Rogue AP’s? Where there is not a firm line that indicates there are “too many” rogue AP’s, however if the number of active rogue AP’s is more than 50% of the total number of AP’s, it’d be a good idea to understand why and possibly take mitigating actions.
Are there any Active Rogue Clients? A “Rogue AP” is one that your AP’s can hear that is not part of your own network. In fact a rogue AP may not be rogue at all, it may simply be an AP used by a neighbor for their own use.  A “Rouge Client” is a client device that is connected to a Rogue AP.
Anything “interesting” in the Most Recent Traps? Look for major events like AP Disassociated, Failed to…, Signature attack, Potential denial of service, temperature too high, etc.
MONITOR -> Access Points -> Radios -> 802.11a/n/ac Look for failures in:

Load Profile (failed means more than 20 clients)

Noise Profile (failed means over -70 dBm)

Interference Profile (failed means more than 25%)

Coverage Profile (failed means a detected coverage hole)

A failure does not necessarily indicate a systemic problem, only an indicator a configured threshold has been crossed.
If you notice a lot of failures in the same area you may want to investigate.

MONITOR -> Access Points -> Radios -> 802.11b//n Look for failures in:

Load Profile (failed means more than 20 clients)

Noise Profile (failed means over -70 dBm)

Interference Profile (failed means more than 25%)

Coverage Profile (failed means a detected coverage hole)

A failure does not necessarily indicate a systemic problem, only an indicator a configured threshold has been crossed.

If you notice a lot of failures in the same area you may want to investigate.

WLANS Top Tab
Are there more than 5 active WLAN’s? The number of SSIDs should be kept to a minimum to avoid a negative performance impact because of excessive management traffic. Each SSID requires a separate beacon message that will be broadcast at the lowest mandatory data rate and can significantly impact the performance in a high-density design.

If you have 20 SSIDs and your 802.11b/g radios are left with the default settings, then the wireless cell is going to slow down to 1Mbps for a significant time window to send beacons and listen for responses.  This happens regardless of how many clients are communicating.  Issues will be very difficult to troubleshoot.

Within Each WLAN
General Tab
Is Broadcast SSID turned on? This is sometimes mistaken for a security feature.  It is recommended to leave Broadcast SSID as some client devices will not roam (or roam efficiently) with it turned off.
Security -> Layer 2 Tab
Is “Fast Transition” set to “Adaptive” (only on 8.3 or newer code) 802.11r Fast Transition is a feature introduced in 8.3 code.  At the time of this writing only Apple iOS10 devices support it.
Fast Transition can be Enabled, Disabled, or Adaptive.  If you want devices that support and do not support 802.11r then be sure to make Fast Transition “Adaptive”.
If WPA is enabled, is TKIP checked and AES unchecked? For those SSID’s that require data encryption and for those SSID’s that need to support legacy clients that do not support WPA2, only use WPA with TKIP and not with AES.
It is desirable to not have WPA enabled at all.
When WPA first came out the preferred encryption type was TKIP (104 bit key + 24 bit initialization vector = 128 bits total).  Later when WPA2 came along AES (256 bits) was added.  Most devices that NEED to use WPA will not be able to use AES.  If AES is enabled it could cause newer devices to use WPA with AES which will not allow 11n or faster data rates.

Read more at this Cisco Support Forums article.

If WPA2 is enabled (and it always should be except for guests or special cases), is AES enabled and TKIP disabled? For those SSID’s that require data encryption, make sure WPA2 with AES is selected and not TKIP.  AES (or no encryption at all) is required to get 11n or faster data rates.
There may be other options. Only select AES unless you are addressing a specific need and understand the implications.
If 802.1x is enabled, is CCKM enabled? Comment thanks to Javier Contreras Albesa: CCKM should not be recommended as a general feature to be turned on, unless you have client supporting it (792x phones, WGB, etc). 802.1x allows for a client authentication of several types (certificate, user ID and password, etc.).  Each time a client roams the authentication need to take place again.  CCKM is a mechanism Cisco has created to expedite that procedure, for devices that support it.

Read more about CCKM on the article 802.11 WLAN Roaming and Fast-Secure Roaming on CUWN

WIRELESS Top Tab
Any AP’s showing administratively down? Are there radios that are showing down?  Is there a known reason for them showing down? It is not uncommon to have some AP’s with radios that are administratively disabled.  It’s good to at least know why.
Are than any AP’s showing something other than PoE/Full Power or Power Injector / Normal Mode? Make sure there is a good reason if there are any AP’s showing something other than full or normal power mode. Most AP’s have a minimum power requirement of 802.1af (15.4W). Some AP’s, including 802.11n AP’s,  need higher power levels in order to enable the fastest data rates.  If a newer AP has reduced power it’s likely the fastest data rates will not be enabled.
What mode(s) is(are) the AP’s in? Make note and understand the implications of AP’s in Flexconnect or Connected (sometimes listed as Local) mode.  If there is a mix of Flexconnect and Connected/Local mode AP’s, make sure you understand why and the implications. AP’s in Connected/Local mode will tunnel all client data traffic to the controller and then be placed on the appropriate VLAN.  AP’s in Flexconnect mode will (typically) place client data traffic on an appropriate VLAN that is trunked to the AP.  Be sure to understand the implications of the desired design.
WIRELESS -> Access Points -> Radios -> 802.11a/n/ac
What channel sets are in use?

UNII-1: 36-48 (4 channels)

UNII-2: 52-65 (4 channels)

UNII-2b Extended: 100-144 (12 channels)

UNII-3: 149-161 (4 channels)

Generally (in the US) it is recommended to use UNII-1, UNII-2, and UNII-3.  Unless you are needing to support legacy devices (pre 802.11n), you should also enable UNII-2b Extended channels, allowing DFS to ensure they are allowed to be used.
How many channels do AP’s use (1 for 20 MHz, 2 for 40 MHz, 4 for 80 MHz) Do AP’s show multiple channels in the Channel column?  If yes, does the number of channels appear to be (at least generally) consistent?
If there are AP’s showing 4 channels in use (80 MHz wide) it will be important to understand why and the implications relating to channel availability.
Are any AP’s showing a channel number without an *asterisk? It is desired to have Radio Resource Management (RRM) manage channel assignments.  If your deployment has specific needs it is best to tune RRM so it makes the best decisions.  Note any channel that does not have an asterisk (*) following it and understand why this radio has a static (manual) setting.
Are any Power Levels showing a number without an *asterisk? It is desired to have Radio Resource Management (RRM) manage transmit power level assignments.  If your deployment has specific needs it is best to tune RRM so it makes the best decisions.  Note any Transmit Power that does not have an asterisk (*) following it and understand why this radio has a static (manual) setting.
Are than any power level 8’s? Power levels range between 1 (100%) and 8 (effectively off).  A power level of 7 is as low as it can go before it is turned off.
Do the power levels tend to be 3’s, 4’s, and 5’s? RRM should have the ability to increase or decrease transmit power levels to account for the always changing RF environment. If AP’s are mostly on power level 1 or 2, they may be placed too far apart from each other. If AP’s are mostly on 6, 7, or 8, AP’s may be too close to each other. In some cases you can account for AP’s being further apart or closer together by modifying the Power Threshold under WIRELESS -> Access Points -> 802.11a/n/ac -> RRM -> TPC.  Start with increments of 3.  Add 3 to get radios to generally be louder.  Subtract 3 to get radios to generally be quieter. The default is -70.
WIRELESS -> Access Points -> Radios -> 802.11b/g/n
Are there any channels in use besides 1, 6, and 11 and is there a reasonable mix of them? Make sure only channel 1, 6, and 11 is in use and there is a reasonable mix of them.  Never use other channels outside of the US.
Are any AP’s showing a channel number without an *asterisk? It is desired to have Radio Resource Management (RRM) manage channel assignments.  If your deployment has specific needs it is best to tune RRM so it makes the best decisions.  Note any channel that does not have an asterisk (*) following it and understand why this radio has a static (manual) setting.
Are any Power Levels showing a number without an *asterisk? Power levels range between 1 (100%) and 8 (effectively off).  A power level of 7 is as low as it can go before it is turned off.
Do the power levels tend to be 3’s, 4’s, and 5’s? RRM should have the ability to increase or decrease transmit power levels to account for the always changing RF environment.
If AP’s are mostly on power level 1 or 2, they may be placed too far apart from each other.
If AP’s are mostly on 6, 7, or 8, AP’s may be too close to each other.
In some cases you can account for AP’s being further apart or closer together by modifying the Power Threshold under WIRELESS -> Access Points -> 802.11a/n/ac -> RRM -> TPC.  Start with increments of 3.  Add 3 to get radios to generally be louder.  Subtract 3 to get radios to generally be quieter.
The default is -70.
WIRELESS -> 802.11a/n/ac -> Network
Are the supported, mandatory, and disabled data rates following best practices? Generally, if the lowest data rates are MANDATORY then clients will tend to experience roaming issues, stickiness, or unexplained dropped connections.

  1. Highly consider disabling all 802.11b data rates of 1, 2, 5.5, and 11.
  2. It is a best practice to AT LEAST make 12 Mbps Mandatory.
Comments thanks to Paul Chapman: Additionally, with 802.11b/g, by not having any mandatory rates above 11Mbps (default setting), you are allowing 802.11b clients on the cell. Unless you have to support them, b-clients are highly undesirable.

I would recommend setting the lowest mandatory rate to the speed you expect to support when clients start to roam, probably 24 Mbps. At a minimum set at least 1 mandatory rate above 11Mbps to prevent b-clients from coming onto the network.

Cisco White Paper: Cisco Wireless LAN Controller Configuration Best Practices

WIRELESS -> 802.11a/n/ac -> RRM -> TPC
Is Coverage Optimal Mode (TPCv1) selected? This is a default and is a best practice for most WiFi deployments.  Typically, TPCv2 is used in very specific circumstances.
Is Power Level Assignment Method set to Automatic? Since the RF environment is constantly changing, it is a best practice to use RRM. If the default settings of RRM are not appropriate for your environment, considering tuning it before changing the assignment method to fixed.
What is the Power Threshold set to? The default is typically -70 dBm.  If it is something other than that, it is important to know why.
WIRELESS -> 802.11a/n/ac -> RRM -> DCA
Is Channel Assignment Method set to Automatic? Since the RF environment is constantly changing, it is a best practice to use RRM. If the default settings of RRM are not appropriate for your environment, considering tuning it before changing the assignment method to fixed.
Is Channel Width following best practices? For high density client environments, it is a best practice to use 20 MHz.  It is typically not a best practice to use 80 MHz at all.  If the version of code you’re using has BEST as an option, this is typically recommended.
Are Extended UNII-2 Channels Enabled? Without UNII-2 Extended there are 12 channels available, or 6 with 40 MHz channels.  By using UNII-2 Extended, an additional 9 channels are available (or 12 channels if you have an AP that follows the new FCC rules (FCC Order 14-30)). Unless you are need to support older client devices that do not support UNII-2 Extended channels, be sure to use them.  It is rare devices do not support them.
Is ED-RRM Enabled? Event Driven RRM allows the RRM process to make immediate changes should a catastrophic interferer cause issue between RRM decision cycles.
WIRELESS -> 802.11b/g/n -> Network
Are the supported, mandatory, and disabled data rates following best practices? Generally, if the lowest data rates are MANDATORY then clients will tend to experience roaming issues, stickiness, or unexplained dropped connections.
WIRELESS -> 802.11b/g/n -> RRM -> TPC
Is Coverage Optimal Mode (TPCv1) selected? This is a default and is a best practice for most WiFi deployments.  Typically, TPCv2 is used in very specific circumstances.
Is Power Level Assignment Method set to Automatic? Since the RF environment is constantly changing, it is a best practice to use RRM. If the default settings of RRM are not appropriate for your environment, considering tuning it before changing the assignment method to fixed.
What is the Power Threshold set to? The default is typically -70 dBm.  If it is something other than that, it is important to know why.
WIRELESS -> 802.11b/g/n -> RRM -> DCA
Is Channel Assignment Method set to Automatic? Since the RF environment is constantly changing, it is a best practice to use RRM. If the default settings of RRM are not appropriate for your environment, considering tuning it before changing the assignment method to fixed.
Are channels other than 1, 6, and 11 in use? It’s important to use channels 1, 6, and 11 for RRM.  Any other channel set should be avoided.
Is ED-RRM Enabled? Event Driven RRM allows the RRM process to make immediate changes should a catastrophic interferer cause issue between RRM decision cycles.

Of course there may be other areas of your controller configuration that may provide health indicators and what works for you (and is healthy for you) may not be what is listed above.  This is simply a way to objectively gauge the health of your controller configuration.

For more insight in to how to tune your configuration, I recommend 3 Steps to Tuning a Cisco WLAN Controller From Default Settings.

Please let me know what you think in the comments section below.

I would like to acknowledge and thank contributors to this article:

5 Amazing New @Cisco_Mobility Features Because of Exclusive Apple/Cisco Partnership

THE EDGE MATTERS! It matters what kind of AP’s we join and what kind of switch we plug in to. There are some who want us to believe the edge is a commodity because they don’t (or can’t) have what we have. Our products are built for digital business with security woven throughout (Be sure to ask about the Stealthwatch (demo) promotion when you buy Cisco ONE licenses!).

I want to bring to your attention a new Cisco Blog article on Spark & the Cisco/Apple Exclusive Partnership. It’s a GREAT one to share on social media! Then as I was putting this note together an article came across my Spark feed:

Neat article on the Cisco / Apple partnership and iOS 10. http://www.zdnet.com/article/cisco-apple-partnership-comes-to-fruition-with-ios-10

How timely! It’s funny though because there’s either super high level descriptions of what these new features are or it’s super technical. The statement “Apple devices work better on a Cisco network” is 100% true and 100% defendable. AND it’s true for both On Premises and Meraki Cloud Managed wireless! Trouble is some of the available detail is way too high level:

  • Higher reliability for real-time applications—66 times decrease in probability of poor audio quality experiences
  • Improved quality of experience—10 times more successful web browsing experience
  • Enhanced network performance—86 percent reduction in network message load from the device during roaming
  • Ease of management—Up to 50 percent reduction in network overhead due to SSIDs

Or it gets vague & overly-technical in the On Premises release notes for the new 8.3 controller code:

  • Fastlane QoS
  • 802.11r Fast Transition
  • 802.11v BSS Transition Support
  • Assisted Roaming
  • EDCA Parameters

So here’s the medium-techie way to describe the new Apple features.  These are available NOW with our 8.3 code for On Premises controllers and AP’s as well as our Meraki Cloud managed solution…

  • Fastlane QoS: With iOS 10 devices customers have the ability to “fast lane” certain applications, granting prioritized network bandwidth to apps with an iOS 10-embedded quality of service (QoS) tag. The new capability offers end-to-end improvement in performance across iOS applications.

(Configure On Premises Fastlane QoS) (Fastlane on Meraki)

  • 802.11r Fast Transition: 802.11r (aka. Fast Roaming) introduces a new concept of roaming where the process of roaming is done even before the client actually moves to the target AP (this is called Fast Transition).

(Configure On Premises Fast Transition) (Configure 802.11r in Meraki)

  • 802.11v BSS Transition Support: Two cool things happen here:
    • Network assisted Power Savings which helps clients to improve battery life by enabling them to sleep longer. As an example, mobile devices typically use a certain amount of idle period to ensure that they remain connected to access points and therefore consume more power when performing the following tasks while in a wireless network.
    • Network assisted Roaming which enables the WLAN to send requests to associated clients, advising the clients as to better APs to associate to. This is useful for both load balancing and in directing poorly connected clients.

(Here’s how to configure it for On Premises.)

  • Assisted Roaming: This is also known as 802.11k. The 802.11k standard allows clients to request reports containing information about known neighbor APs that are candidates for roaming.

(Configure On Premises Assisted Roaming) (Configure in Meraki)

  • EDCA Parameters: Enhanced Distributed Channel Access (EDCA) parameters are designed to provide preferential wireless channel access for voice, video, and other quality-of-service (QoS) traffic. This new version of code gives much better control to network administrators.

(Configure & tune On Premises EDCA) (Configure Meraki Bandwidth and Traffic Shaping)

Please comment below and share this article and ask your Cisco reseller/sales team about the Cisco & Apple partnership and how you can be ready to take advantage of these amazing features.

The 5 Major Features of @Cisco_Mobility HDX and How To Turn Them On

HDX is acronym speak for Cisco’s High Density Experience, which is marketing speak for a series of patented features that specifically address the challenges that stem from the ever growing number of WiFi clients and their need for more reliable, higher bandwidth network access.

The truth is in order to be WiFi Compliant, especially in the early days, certain things needed to happen by default. These default settings may have worked a few years ago but today, even though you’re using high-end AP’s and trusted code levels, you may be getting unacceptably poor performance. This is why I wrote up 3 Steps to Tuning a Cisco WLAN Controller From Default Settings. In just a few minutes of configuration time and a radio reset, you may experience exponential performance gains.

Tuning a WLAN controller only solves part of the problem.  This is especially true as your deployment begins to take on more clients, demanding more bandwidth. What kind of symptoms will you experience?

  • Clients are still in charge of deciding when and where to roam.
  • If you elect to use them, 802.11ac introduces larger channel widths meaning we’re more vulnerable to interference.
  • With WiFi only one client can talk at a time… it’s half duplex.  As clients get further from an AP they begin to talk slower to stay connected, leaving less time for fast clients to talk fast.
  • AP’s are getting closer together to accommodate more clients, and there are limited RF channels we can use.  Even with the newer FCC rule changes adding more available channels, it’s mostly good news for 11ac environments.

To solve these problems we need Optimized Roaming, CleanAir for 80 MHz Channels, ClientLink 3.0, Air Time Fairness, and Turbo Performance! Let’s dive in to what buttons to press, which options to check, and how to get it all working for us.

1. Optimized Roaming

What’s the problem: Client stickiness. The 802.11 standard says clients can roam. As such, it’s the clients responsibility to decide when and where to roam… they just don’t do it very well. Normally the client will not even TRY to roam until it can no longer connect at the lowest mandatory data rate. This is why I recommend turning off the lower data rates, suited to your environment. We are preventing the client from being really bad, not promoting good behavior.

What it is: Optimized Roaming promotes good behavior. If the client’s data signal strength dips 6 dB the AP will send a disconnect message, prompting a roam. You can optionally set a minimum data rate. If the clients tries to dip below the minimum, it’ll get a disconnect message, prompting another roam. Use caution here. If the client cannot connect at the minimum data rate, it won’t be able to connect at all.

How to turn it on:

  • Wireless > Advanced > Optimized Roaming
  • Check the Enable box in the 802.11a and 802.11b sections
  • Note you’ll get a warning: Modifying the default settings for the Optimized Roaming data rate and CHDM RSSI configurations could result in unintended client connectivity problems. Please be careful when making changes from the default settings
  • Reference from the 8.1 Configuration Guide

2. CleanAir for 80 MHz Channels

What’s the problem: It’s great that 802.11ac provides for greater bandwidth. It does that by using more spectrum, the channel is wider. More channel space means vulnerability to more interference. Interference is that that invisible threat that decreases overall throughput which often presents during times of load and is very difficult to troubleshoot.

What is is: CleanAir for 80 MHz Channels uses the built-in spectrum analysis of the Cisco AP to discover, identify, classify, and, most importantly, mitigate interference. Right away.

How to turn it on: CleanAir is OFF by default. So step one is Turn It On. It will automatically detect, identify, and classify. What we need to turn on is turn on 80 MHz channels and the Mitigate part of CleanAir. To do that got to Wireless > 802.11a/n/ac > RRM > DCA. There change the channel width to Best and at the bottom you need to make sure Event Driven RRM (ED-RRM) is Enabled. Note: By selecting the “Best” channel width, you are allowing the system to automatically back down the channel width if interference does not allow high-performance at 80 MHz.

3. ClientLink 3.0

What’s the problem: As a client gets further from the AP the signal strength from that AP get weaker. As a result, because it’s not yet time to “roam” it ends up lowering its data rate. It talks slower in order to stay connected. WiFi is a shared medium, meaning only one station (client or AP) can talk at a time. If a client is talking slow, there’s less time for the fast talkers to talk fast.

What it is: It’s fun with physics and it doesn’t need any client-side intelligence to work. So 802.11n introduced something called MIMO. It’s basically some fancy antenna technology that allows the AP to communicate with a client using multiple antennas at once. As seen in this 1 minute video called ClientLink at the Beach, when the transmissions from two or more antennas meet, they create a sweet spot of coverage. If your client is in that sweet spot, they’ll experience higher signal strength, and likely connect at a higher data rate. What is DOES is detect when the client is not in that sweet spot and it starts to manipulate the transmission timing on the multiple antennas putting a sweet spot right on the client.

How to turn it on: It’s on by default and works with any WiFi client out there that supports 802.11 a/g/n/ac!

4. Air Time Fairness (ATF)

What’s the problem: Guest users can potentially take up their unfair share of bandwidth downloading app updates or movies, degrading your business related WiFi traffic. Per-user bandwidth contracts only go so far. Because clients connect at different speeds, simple rate limiting is not efficient for WiFi.

What it is: Cisco Air Time Fairness allows us allocate an ability to consume bandwidth based on a defined group such as guests or smart phones. Regardless of a clients connected data rate, it can only talk a certain percentage of the time.

How to turn it on: Since you need to identify your groups and allocations, it’s not on by default. It’s a good idea to run ATF in monitor mode to understand actual bandwidth usage by SSID, by AP, or by a group of AP’s. Understanding that you can define and apply a policy.

  • Turn on ATF Monitor Mode

In the Wireless > ATF > Monitor Configuration menu select “Network.” Put a check next to 802.11a and 802.11b and click the enable button.

  • Configure ATF Policy

Here’s where a bit of planning helps. Remember that a policy is applied to an SSID, to an AP, or to an AP Group. First take a look at your actual Air Time allocation. Click on Wireless > ATF > ATF Statistics. Select an AP you want to see Air Time stats on. The top table shows you allocation over the last 3 minutes. The bottom table shows allocation as long as the radio has been up. Use this to determine the relative impact by enforcing “fairness.”

In the Wireless > ATF > Policy Configuration menu you will notice a policy ID 0 called “Default” with a weight of 10. This default cannot be changed, but don’t worry, you don’t need it to. Define all of the policy elements here. So if you want 75% employee allocation and 25% guest, you’d create 2 elements with appropriate weights. If you are building policies for multiple SSID’s or AP’s, just group them all together.

  • Apply the policy

Click on Wireless > ATF > Enforcement SSID Configuration. If you’ve followed the steps above, your radios will be in ATF Monitoring mode. Here is where you with them to “Optimized” mode or “Strict” mode enforcement. As it sounds, Strict mode enforces hard limits. Optimized allows for spiking above the policy if possible.

In the Policy Enforcement section you specify an SSID and a ATF Policy ID to enforce.

For a way more technical description check out the Cisco Air Time Fairness White Paper.

Cisco Air Time Fairness in the Configuration Guide

5. Turbo Performance

What’s the problem: As your network scales to many more devices with greater bandwidth needs, it won’t matter how fast we’re connected if we can’t process packets. With 802.11ac we’re processing nearly double the packets as with 802.11n! We could address this with a faster CPU but that’s an expensive upgrade.

What it is: Commodity hardware and chipsets need to have a central CPU to process packets. With Turbo Performance, Cisco dedicates CPU & RAM to each RADIO to perform packet processing at the edge. This is much more efficient than having a central processor do everything.

How to turn it on: You’re in luck! You have nothing to do to take advantage of this feature.

So this HDX… High Density Experience… is more than just marketing speak. It’s a set of patented technologies that show how hardware is just as important as software and something only Cisco can deliver.

  • Optimized Roaming
  • CleanAir for 80 MHz Channels
  • ClientLink 3.0
  • Air Time Fairness
  • Turbo Performance

For more information check out http://www.cisco.com/go/80211ac.