The evolution that will start the revolution

You’ve heard it all before, evolutionary technology versus revolutionary technology. Everyone wants their newest technology to be revolutionary – expecting it to be life changing and a wide-sweeping, compelling reason to spend tons of money. This is rarely the case and more often than not marketing fluff to try and get you onto the next big thing. Occasionally we get such an unassuming technology announcement that fits squarely in the ‘no big deal’ from a speeds and feeds perspective that it’s easy to overlook. This is clearly the case with the recent multigigabit announcements from Cisco during Cisco Live, Milan. Multigigabit is a technology that allows your existing cabling to support speeds in excess of 1G, without having to make the jump all the way to significantly more costly 10G. Since we already have technology that address speeds and feeds above what we’re talking about here (how many 10G uplinks have you deployed recently?), it’s easy to overlook the impact this will bring to our daily lives. The ability to move to 2.5G and 5G link speeds without having to make the jump all the way to 10G will allow us to get improved link speeds without having to pay a premium for them. The expected cost increase is estimated to be anywhere from 0% to 15% according to the rumor mill which makes the 250% to 500% speed bump quite attractive!

802.11ac wave 2
The reason I’m taking about it is the fact that this brings with it the promise of addressing the 1G bottleneck that people have been gnashing their teeth over in the wireless space for the past couple of years. While we’ve been able to reasonably deflect the speeds and feeds conversation with 802.11ac wave 1 (speeds approaching 1G wired requirements), there has been no good way to move past that without having a two-cable conversation. The assumption up till now has been that 2x 1G links will be the way forward and many people have been running two copper runs out to their Access Points for the past several years in anticipation of this approach. 802.11ac wave 2 will undoubtedly break the 1G barrier in fairly short order with speeds being promised of (best case) 6,930Mbps PHY rate (about 4,900Mbps on the wire). Multigigabit solutions will allow us to address these concerns without having to invest in 10G links. Better yet, it will allow us to address these concerns without having to consume two 1G ports on our switches. Regardless of the solution you choose (1x 10G or 2x 1G), the cost for deploying a single Multigigabit link supporting up to 5G will be less at scale.

The other unassuming byproduct of this conversation is that Access Points require power to bring up all of those components. It will be nearly impossible to power up a 10G ethernet interface in an AP in the power budgets that we have today. By reducing the link speed requirements to 5G, we can save power at the edge device and still fit in modern negotiation. Multigigabit solutions today will provide PoE, PoE+, and UPoE to ensure that the wave 2 APs that we’re going to be hanging will have ample power for whatever they’re going to bring.

The Revolution
I predict that the incremental cost and intermediary speeds will allow us to start having conversations about the jump to 10G. Multigigabit solutions on Access Points, switch uplinks, and desktop and server nics will be the next big thing. Stackable solutions today promise backwards compatibility so you don’t have to rip and replace – just add a stack member and you’re good to go in that closet/IDF! Regardless of your future proofing plans, enabling faster wireless, or just ensuring that you’re not spending money after (can you believe it?) now legacy 1G infrastructure, make sure you’re having a conversation today about ethernet to bridge the gap to 10G.

For more information about the NBASE-T alliance, go here.
For the Cisco Live, Milan – Tech Field Day Extra event with Peter Jones, go here.


You can have my Cognio card when you pry it from my cold dead hands

There is a group of WiFi Professionals (me included) that just can’t let go of their Cognio based products. With the Cisco purchase in 2007 (which ultimately manifested itself in the CleanAir product) we have seen a slow but steady decline of high-fidelity PC based spectrum analyzers. We’ve seen people try to compete in a variety of ways; with lower fidelity devices (Metageek) or with the high cost BandSpeed based product (AirMagnet Spectrum XT) but it’s not rare to find a wireless professional still lugging around an old laptop to use their Cognio based (AirMagnet Spectrum Analyzer, Cisco Spectrum Expert, or Cognio Spectrum Analyzer) CardBus Card. It seems unlikely that we’ll see a USB based Cognio product anytime soon (if ever) so I thought it was high time to figure something else out.

Option 1) For years many of the lager laptops from Lenovo (and even Apple!) have sported ExpressCard slots. By using an Addonics ExpressCard34 to CardBus converter, you can load the Cisco Spectrum Expert software on in Windows and your card works just fine!


  • It works!


  • It requires an ExpressCard34 slot on your PC.
  • There are several converters on the market. Some work, some do not. Make sure you get one that maps the PCIe bus, not the USB bus.
  • It’s bulky the whole card fits outside of the machine and it’s not very pretty.

Cognio adapter in an Addonics converter

Option 2) The Sonnet Echo ThunderBolt to ExpressCard34 adapter will allow you to take the above Cognio/Express card solution and map it to ThunderBolt compatible interface on your laptop. This means that any MacBook past the Early 2011 MacBook Pro (which I’m using) or any PC with a ThunderBolt compatible interface (many modern Lenovo machines) now have a cable-attached (important for flexibility) way to use their Cognio, PC-based Spectrum analyzer on new hardware!


  • It works without having a built in ExpressCard slot!
  • It’s cabled so you can move/relocate the whole bulky assembly to the back of your laptop lid easily.


  • It requires a ThunderBolt port on your laptop.

Big, but relocatable thanks to the cable!

It should be noted that both of these solutions will not work through a hypervisor (VMWare Fusion or Parallels, for example) and require direct access to the PCIe bus – this means running Windows natively on your hardware. You Mac users, this means BootCamp. It should also be noted that many people call ThunderBolt many things and there are several varieties of the bus. Make sure it’s not a DisplayPort only interface!

In short, if you’re still lugging around an old laptop just for this (or any other wireless CardBus based adapter), you now have a solution that’s cheaper than an new AirMagnet card and far less bulky than carrying around that crusty old XP machine. It’s time to upgrade!

Make sure it's ThunderBolt!

Drag racing the bus

Picture it. You’re a school district transportation engineer. You’re in charge of purchasing a fleet of new school busses for your district. The big ones. The expensive ones. The ones that will last you for the foreseeable future. So, you call up Bus Vendor A, B, and C and inform them that you’re in the process of selecting a fleet of new school busses. The following week each vendor dutifully delivers their ‘bus of choice’ to be evaluated. You then grab your intern, put him at the midway point of the bus from ‘Vendor A’ and take it for a spin! You see how fast it goes from 0 to 60. You see how it corners. People hear tires screeching from all over the city as you and your one other occupant sling this bad boy around town ‘evaluating’ the bus. You then repeat the same process for ‘Vendor B’ and ‘Vendor C’. You aggregate your data. You correlated your data. You make pie charts about your data. You do ROI calculations on your data. You do comfort analysis on your data. You do handling analysis on your data. You made your ‘educated’ recommendation and purchased a fleet.

Day 1 of school rolls around and the first thing your brand spanking new fleet of school busses does is immediately do the one thing you neglected to test: they loaded up with kids and trudged along at 20 MPH safely around town. You start getting complaints. They don’t stop well. They don’t handle well. They don’t get good gas mileage. They bounce all over the place and your district has to send 2,000 kids to chiropractic care because you didn’t evaluate the bus under the conditions it’s going to be used in. Instead, you took it for a joy ride. You drag raced it. The one bus that went the fastest with a single guy in it, you bought. When you deployed it, it broke because you didn’t test it using real world scenarios.

Please, don’t drag race your evaluation Access Points. Test them like you’re going to operate them. That way you get a realistic view of how they’re going to behave in the real world. Do your self a favor. Stop joy riding your vendors gear and put it in the real world to test it.

This blog inspiration courtesy of @florwj . Go follow him. He’s awesome.


Cisco releases new WLC UI, Changes default values (finally)

Cisco released WLC code version which brings with it (among other things) a new User Interface for the 2504 WLC. When you use the new simplified setup, it also changes many of the default values that haven’t yet been enabled by default in the base code. The new default values are:

Aironet IE: Disabled
DHCP Address Assignment (Guest SSID): Enabled
Client Band Select: Enabled
Local HTTP and DHCP Profiling: Enabled
Guest ACL: Applied
CleanAir: Enabled
Event Driven RRM: Enabled
Event Driven RRM Sensitivity, 2.4GHz: Low
Event Driven RRM Sensitivity, 5GHz: Medium
Channel Bonding, 5GHz: Enabled
DCA Channel Width: 40MHz
mDNS Global Snooping: Enabled
Default mDNS profile: Add better printer support, Add HTTP
AVC (no Control, only Visibility): Enabled*
Management via Wireless Clients: Enabled
HTTP/HTTPS Access: Enabled
WebAuth Secure Web: Enabled
Virtual IP Address:
Multicast Address: Not configured
Mobility Domain Name: Name of employee SSID
RF Group Name: Default

*AVC stands for Application Visibility and Control. Control means remarking or blocking – for the purposes of the default setup, you’re inspecting only, Control is disabled and must be enabled manually. This also requires a current boot loader which should only be important if you’re setting up an older unit that’s been cleared.

You should note that to get these default values auto-set, you must use the new setup wizard – if you do the regular CLI setup of your controller, or if you just upgrade an existing controller without clearing it’s config, these are not set. You should also note that, for now at least, this only applies to the 2504 controller, not the 5508, WiSM2, 7510, 8510, or Virtual WLC platforms.

WPA/TKIP only going away in Cisco WLC release 8.0

Cisco is readying the next major release of their WLC code, version 8.0. At the advocation of the WFA, this will bring with it a very significant change in security capabilities that you may find impacting if you’re caught unaware. In an attempt to raise awareness, Cisco has approved an discussion of this change first mentioned here. Cisco, in accordance with the new WFA guidelines, will no longer be allowing an SSID configuration with WPA/TKIP only security. If you are currently using an SSID that has WPA/TKIP only security, your configuration will automatically be updated to enable WPA2/AES connectivity as well as WPA/TKIP. You may want to start validation testing now if you are currently supporting legacy devices on a WPA/TKIP only SSID today. The easiest way to ensure you’re not caught by this change is to enable WPA2/AES along with WPA/TKIP and check to make sure your devices still behave as expected. I have confirmed in the lab that this change will be automatic:

WPA-TKIP only configuration pre-8.0

WPA-TKIP only SSID configuration, Pre-8.0

WPA2-AES added post-update

Same SSID with WPA2/AES enabled post-update.


To summarize of the variety of allowed and disallowed potential configuration options you have available and if they’ll be supported in WLC 8.0:

WPA1-TKIP (Disallowed due to eliminating TKIP)
WPA1-AES (Allowed by Extension Policy)
WPA1-TKIP/AES (Disallowed since not used in conjunction with WPA2-AES)
WPA2-TKIP (Disallowed due to eliminating TKIP)
WPA2-AES (Certified and allowed)
WPA2-TKIP/AES (Disallowed due to WPA2-TKIP)
WPA1-TKIP + WPA2-TKIP (Disallowed – no AES support)
WPA1-TKIP + WPA2-AES (Certified and allowed)
WPA1-TKIP + WPA2-TKIP/AES (Disallowed due to WPA2-TKIP)
WPA1-AES + WPA2-TKIP (Disallowed due to WPA2-TKIP)
WPA1-AES + WPA2-AES (Allowed by Extension Policy)
WPA1-AES + WPA2-TKIP/AES (Disallowed due to WPA2-TKIP)
WPA1-TKIP/AES + WPA2-TKIP (Disallowed due to WPA2-TKIP)
WPA1-TKIP/AES + WPA2-AES (Allowed by Extension Policy)
WPA1-TKIP/AES + WPA2-TKIP/AES (Disallowed due to WPA2-TKIP)

Other SSIDs and security configurations are not impacted, including Open SSIDs, any SSID that currently has AES enabled, and WEP SSIDs.


UPDATE: Due to user feedback, Cisco and the WFA finally settled on making the above restrictions in the GUI only. If you still have a business need for a WPA/TKIP SSID, you can configure it from the CLI. If you were building an SSID on a Cisco WLC with an ID of 6, you would use the following commands for example:

config wlan create 6 TKIP-ONLY
config wlan security wpa wpa2 disable 6
config wlan security wpa wpa1 enable 6
config wlan security wpa wpa1 ciphers tkip enable 6

Using the show commands you can validate that this configuration took at the CLI:

show wlan 6

Wi-Fi Protected Access (WPA/WPA2)…………. Enabled
WPA (SSN IE)…………………………. Enabled
TKIP Cipher……………………….. Enabled
AES Cipher………………………… Disabled
WPA2 (RSN IE)………………………… Disabled

Meraki: The bolt on Cloud that wasn’t

When Cisco acquired Meraki last year, there was much confusion. Being ‘down in the trenches’ I struggled as much as the next guy trying to wrap my head around the acquisition and I believe I have a good handle on it. Others not so much. I regularly consult with customers that are just as confused today as they were last year. Cloud is such an over used buzz word and so many vendors are trying to jump on the buzzword bandwagon de jour that it’s easy to get lost admist the jargon and solutions, much less the technical merits or differences in the platforms. I’m here to offer some advice on the strategy and perhaps a perspective on the acquisition that you haven’t yet considered. First some advice:

Don’t purchase Meraki Access Points. You read that right. Don’t do it. Also, don’t purchase Meraki switches. For that matter, don’t buy the Meraki firewall either. If you purchase a Meraki Access Point, a Meraki switch, or a Meraki firewall, you’re not buying an Access Point, you’re not buying a switch, you’re not buying a firewall. You’re buying ‘The Cloud’. When you consider purchasing infrastructure equipment that is ‘Cloud Enabled’, this should be a purchase that lines up with your organizations Cloud Strategy first and foremost. Don’t have a Cloud Strategy? Don’t be so sure. There are a few questions to ask yourself before you jump to that conclusion. Does your organization use DropBox? Office 365? Webex or Goto Meeting? Google Mail? All of these are examples of Cloud Applications. If you use these, someone, somewhere in your organization has made the determination to embrace services from ‘The Cloud’. Understand this strategy. Understand what this enables. Understand what this means to your data and where your data lives. Then (and only then) should you consider purchasing ‘Cloud Managed Infrastructure devices’.

Let’s be frank about it, there’s nothing special about the hardware in a Meraki Access Point. There’s nothing special about the hardware in a Meraki Switch, nothing special about the hardware in a Meraki firewall. When you purchase Meraki equipment, this gear is purpose built to be Cloud Managed with features driven by that Cloud Management. When you make a Meraki purchase, purchase an end-to-end Cloud-enabled infrastructure. If it’s right for one component, it’s right for all of them. If it’s not right for all of them, it’s not right for any of them.

Now some perspective. Everyone is talking about Cloud. Everyone wants in on the Cloud action. Everyone is ‘bolting on’ Cloud to their existing products in some fashion or another. When Cisco purchased Meraki, they made a decision to not ‘bolt on’. They decided to pick the one organization that understood Cloud from bottom to top and embrace that strategy despite the fact that there was some hardware overlap. The Meraki acquisition wasn’t about Access Points, switches, or firewalls. It was about finding the one organization that was never built for ‘on premises’ management and this shines through in every aspect of their products. Others tout ‘free protocols’, ‘cloud provisioning’, or a variety of other nonsense but at the end of the day, these are bolt-on solutions that are all afterthoughts. I would encourage you to revisit the Meraki product portfolio but when you do, ask yourself the following questions:

  • What are my existing Cloud Applications?
  • How do I rely on ‘the Cloud’ today?
  • Do I want to leverage that existing strategy in my infrastructure?
  • Do I want a solution that is built from the ground up around ‘the Cloud’ with a no-compromises featureset or do I want to deal with someone bolting on features to their existing ‘heavy gear’?

Then go buy a Meraki AP.

Bridging networks on a VM

So, you’ve got your shiny new Mac and you’re in that ‘in-between’ time where you’re running a VM to support all of your Windows needs. You decide that your VM needs to be connected to the same Layer 3 network as your physical box so you decide to change your VM network settings from ‘NAT’ to ‘Bridged’. This seemingly simple configuration change has some pretty significant ramifications in the Cisco wireless world however so you may be shocked to find out when you take your beloved Mac back to work that your VM stops getting an IP address! As it turns out, there is a feature enabled by default on a Cisco lightweight wireless infrastructure that is spelled out thusly:

In the controller software Release 5.2 or later releases, the controller enforces strict IP address-to-MAC address binding in client packets. The controller checks the IP address and MAC address in a packet, compares them to the addresses that are registered with the controller, and forwards the packet only if they both match. 

Since your Mac(intosh) uses a single adapter (your WLAN adapter) for the connection to the network, the controller only sees a single MAC address. This means that it will only let a single IP address talk on the network since it’s expecting a 1:1 mapping of MAC address to IP address. The quickest way around this is the following global command on your WLC:

config network ip-mac-binding disable

Which will remove this 1:1 mapping expectation. Don’t forget to save your config and you should be good to go with IP addresses issued via DHCP to both your real machine and the Virtual Machines living behind the bridged VM network!

It should also be noted that many ‘security appliances’ serving as your DHCP server will refuse to issue multiple IP addresses to a single MAC address, effectively recreating identical symptoms (a VM that get’s no IP address). As far as I know, there is no workaround aside from not using a security appliance for your DHCP server. This is believed to afflict both Palo Altos as well as ASAs and is likely to impact anything else under the guise of a ‘security appliance’. Your best bet is to try and put DHCP services on a real server (Windows DHCP or Linux ISC-DHCPD) or try running it in IOS on your next hop Catalyst switch. You *do* have a next-hop Catalyst switch, right? 🙂