When upgrades are not about technology

While at a customer’s slightly unusual site (let’s just say, heavy machinery with very custom hardware and applications) they suggested upgrading their wireless installation to the latest technology.  Suddenly foretelling an unanticipated event while upgrading – and subsequent disruption to production, a brief look of alarm crept out.

Actually, similar to the somewhat alarmed look my wife gives me when I reach for another piece of cake.  A look that urges one to ‘reconsider’.

The existing solution works fine, quite well in fact.  The known cost and unknown consequences (for now) of such an upgrade activity were a little alarming considering the as yet unproven benefits of a new solution working with their existing custom devices.

Turns out however, the upgrade had nothing to do with improving the WiFi.  Bigger things were happening; which would impact the wireless network.  And while not near end of support, the existing wireless network in some parts is four years old.  So, End-of-Life in accounting terms.  We all know that the bean counters love to have expensive new items to depreciate.

All the customer needed from me at this time was to call out anything they might be missing.  I noted a couple of things for consideration and then basically, got out of the way.

Reminder to self: technology upgrades may not always be about the technology.  They may be just be a side impact of bigger commercial decisions that are going ahead.

As for the wireless installation, don’t know what I was worried about.  Might have some cake to celebrate.

How to get 1.3Gbps throughput over WiFi

Most manufacturers advertise impressive speeds of up to 1.3Gbps (Gigabits per second) for their latest WiFi gear.  That’s pretty quick.

However, WiFi is a half-duplex technology that relies on substantial protocol overhead to transmit and receive. 1,300Mbps is actually only roughly 650Mbps in the equivalent wired domain, the domain that we are used to comparing speed and throughput.  Also, that target of 1300Mbps will not have a sustained throughput rate like a wired connection, it will be decidedly ‘spotty’.

That said, to get 1.3Gbps [half-duplex] throughput on your WiFi, start with a high performance enterprise-grade wireless Access Point (AP) and a modern high performance laptop i.e. minimum of 3x antennas built-in.

Next, we need to remove everybody else’s devices.  Turn off EVERY other WiFi capable device within 100 metres.  This includes all devices outside of your control.  Neighbouring WiFi modems and wireless Access Points, all other laptops, tablets, smartphones, SmartTVs, Chromecast, Apple iSomething, microwave ovens, IoT emitters, baby monitors and so forth.  Nothing else should be left on.

By now, we must be in a cave somewhere.

Next: tune the specific enterprise-grade features on the AP for high-performance.  Left at default parameters out of the box, key settings critical to high performance would not be enabled.

Then (very important): place laptop within 3 metres (10 feet) of the AP.

Alternatively: go to a specialised wireless testing facility where just you and your laptop sit in a special little room that repels all wireless interference (roughly akin to a recording studio with soundproof walls).

Either way, this is the only way that we will come even close to the advertised speed.

Back to the real world.  Undoubtedly, from time to time your laptop may be in an insanely good position relative to the AP and environment and advise that your connected data rate is indeed 1300Mbps.  In the wired world, this would actually be what you are getting.  In the wireless world, this is not what you get.  You get (substantially) less.

Consider the wireless data rate to be similar to the maximum speed on a car’s speedometer.  Your actual speed, will be limited by the traffic and environment around you.  Just like wireless.

Where Minor Adjustment = Big Improvement

Sometimes we need to adjust the car radio dial a little to avoid crackly interference and receive a cleaner signal.  A minor adjustment, a millimetre or two to the right or left, can make all the difference.  When that wireless radio signal is being affected by external interference, there is an audible impact; our personal antennas (our ears) pick that up and we go about trying to improve it.

So how do we achieve that with WiFi?  How does one make those slight, minute adjustments that may improve wireless performance by 20%?

Professional Analysis is the answer.  The ability to understand the data presented by specialised software allows wireless network professionals to know where to make those minor tweaks that result in measureable performance improvements.

The key thing to realise here is that the solution maybe quite simple but the general user just doesn’t have the toolsets or the knowledge to find those simple settings to tweak.

Remember the old story of when a factory called a guy to fix a sudden stop in machinery; he came in, examined it, then used a hammer to tap a particular point and bingo, everything started working. His subsequent bill of $200 for the work was questioned.  His simple response, “For the tap, $10. For knowing where to tap, $190.”

 

 

Netflix on the business network

While the network is carrying business critical applications, all well and good.  But Netflix and Soundcloud streaming?  They’re usually red flags.

Enter Application Awareness. One of the most useful outcomes from deploying enterprise-grade wireless is obtaining valuable insights into what the network is actually busy doing and the ability to act upon that information automatically.

The network is an asset that an organisation uses like any other tool to run its business.  Having visibility into how that asset is being utilised is of tremendous value.

Application Awareness leads to a higher level of detailed visibility into an organisation’s actual, ground-level operations, of how users are using the network services.  From this a business is able to identify trends, prevent threats, or recognise that it may need to improve the overall service experience e.g. an increase in capacity.

Many enterprise wireless vendors build Application Awareness into their products.  They also make it easy for administrators to enforce a differentiated service based on profiles;  triggered by application sensors built into the product.  When sensors detect a voice call for example, a certain level of network resources can be awarded to it.  When the sensors detect music streaming, the network can be configured to respond to that differently.

The system can generate regular reports on all of the above, including the health of the network.  The information that these reports provide to the business becomes valuable from Day 1 and indispensible in supporting and optimising the utilisation of this business asset.

An organisation that before was somewhat blind to what the Wi-Fi was busy doing, and not entirely sure of how their asset was being utilised, now has valuable insights and an input for future planning.

CWNE Certification – A personal goal

I thought I’d share this goal of mine that I’ve been thinking about, talking about and worrying about for some years now: to become a CWNE, a Certified Wireless Network Expert.  To a wireless network professional, one who specialises in Wi-Fi, this qualification is a big thing, the top of the certification path in wireless networking.

CWNE is the highest certification awarded by CWNP (www.cwnp.com), the vendor-neutral organisation that administers the CWNP exams and, in a few days time, I’ll formally submit my application.

So I’m close. Last week, I passed the last exam I needed to pass in order to complete the ‘exam requirements‘ part of the formal application process.  I already had the basic exams, CWTS and CWNA, which I took in 2012.  But to apply for CWNE status, you need to pass:

  • CWDP – Certified Wireless Design Professional
  • CWAP – Certified Wireless Analysis Professional
  • CWSP – Certified Wireless Security Professional

With good reason, the most common advice is to take CWAP first, which gives you an excellent base to understanding 802.11 and its inner workings.

My particular exam path was quite the opposite.  In 2013, security was a weakness for me and I needed to turn it into a strength.  So CWSP was my first exam and I studied pretty hard for it.  Passed it first go in March 2014.

Due to some work projects I knew were coming up and would interrupt my plans for studying at the same pace as CWSP, I decided to halve the amount of time I felt I needed for CWDP and sat the exam just a few months later.  CWDP is not an easy exam (well none of them are) but I was particularly surprised by this one.  Anyway, I failed the exam by a question or two.  Twice.  Got it the third time.

That left CWAP and the thought of CWAP quite frankly scared me (which is why I did CWDP second). I was that worried about my ability to remember complex protocol field mappings and modulations; recognise patterns in Spectrum Analysis and memorize 802.11 headers, sequences and operational processes; that early on I decided to do an authorised CWAP course. In Bangkok. I signed up to Globeron’s CWAP course (taught by Ronald van Kluenen) and it was superb.  From that course, apart from the knowledge learned at the course I obtained two key takeaways: first, an official  CWAP course notebook which is chock-full of impressive tips and notes, and second: self-confidence.  During that course I realised that I was not as far off being prepared for CWAP as I thought I was. It was a massive confidence boost.

Due to work commitments, it took a year for me to prepare and finally sit the exam and happy to say it was last week that I took it and passed.

I would like to mention that all of the CWNP books (published by Sybex) have been superbly written. They really, really have and my hat goes off to the authors of each book.  The books explain technical concepts extremely well. You still need more material though. Luckily there are blogs by CWNEs and whitepapers by universities that are a wealth of information.

Colleagues often ask me why not go for a vendor certification?  Xirrus, Aerohive, Cisco, Aruba, Ruckus, HP all offer their own wireless certification tracks. While these are all valuable in their own right, for what I wanted to achieve, I decided early on for a globally recognised, independent certification.  It suited me for two reasons:

  1. I wanted to focus on learning the IEEE 802.11 standard and how it is applied in the real world in different environments.
  2. I required a flexible, adaptable skillset that could be applied to any situation to troubleshoot issues and audit complex scenarios on any customer implementation, regardless of their chosen brand.

Some curious colleagues (and the odd customer) have also asked me about the Wi-Fi tools I use.  Well, below is what I use but there are lot of awesome tools out there and I would have them all if I could! Principally I use:

  • Tamosoft Tamograph Site Survey (Site Survey software)
  • Tamosoft CommView for Wi-Fi (WiFi Layer-2 Analysis software)
  • Metageek Chanalyzer Pro and a 2.4/5GHz Metageek WiSpy dBx adaptor (Spectrum Analysis)
  • A custom Toshiba Portege laptop that is very thin and extremely light – when walking around sites for hours, you need something that isn’t heavy!

Plus a bunch of other networking tools I’ve used since CCNP and CCIE R&S days.

In summary, from Day One I have wanted – and I truly desire to be, an independent expert.  To be able to offer my customers the best solution for their needs.  While this may be one vendor for one environment, as a consultant I would (and do) recommend another vendor for a different environment which I feel best matches my customer’s current and future requirements.

Getting to this point has been a worthwhile journey.  I have learned an incredible amount of VALUABLE information that helps me every single day of my job.  My networking background has been routing and switching and although it is a job I enjoyed, it was always ‘a job’.  However, wireless and radio frequency operation fascinates me and its not just a job. I’m passionate about it.

To date, it has been an exceptionally rewarding experience.

A Guide to Wi-Fi Requirements.

Do you know what you want, what you really, really want?

Sometimes we need to flesh out real requirements for a Wi-Fi service.  A common request from customers is simply, “Install Wi-Fi at xyz location”.  Actual requirements start with understanding the desired outcome or performance expectations and working backwards from there.

There are relevant questions.  Such as what type of user experience is required and what density of users will be simultaneously using the Wi-Fi service. Or what existing systems does the service need to integrate with?

Business questions first.  If we don’t understand the business reasons for wireless in the first place, we won’t be able to design a solution that meets expectations.  Why is the business investing in a wireless service, what are the required business outcomes and timelines and how will the business measure the success of the installation?  What applications will they run and what type of activities do the business expect users to perform over the wireless medium?

Technical questions that address wireless functionality naturally follow. The customer may have standards that must be followed to integrate a wireless service:  user authentication, encryption, device management, reporting, logging, wireless intrusion detection (and desired responses), application performance, density of users, or different user groups.

From answers to these business and technical questions, we are able to begin noting the Wi-Fi requirements.  The discovery phase will assist here:  identifying supporting infrastructure, is there adequate bandwidth for the solution, is Quality of Service (QoS) required for application performance and which 802.11 standards need to be supported.

During the process of discovery, in some situations we may find that a Wi-Fi solution will not actually be fit for purpose!

The physical environment where wireless service will be installed prompts its own questions.  If site access for an inspection is difficult: a picture tells a thousand words.  A few well-chosen photos of the wireless environment will tell us a lot about what needs further analysis.  The environment will mandate if internal or external (weatherproof) Wi-Fi equipment is necessary, if internal or external antennas will be required, where there may be coverage challenges and so forth.  Physical security of equipment inside the environment should also be taken into consideration.

Site surveys are crucial.  We will want to know if the proposed environment is subject to wireless interference or,  if it has to contend with 50 foreign Wi-Fi networks fighting for the same channel space.  Site surveys can discover useful information that then become technical requirements that feed into the design.  For example, if a site survey uncovers heavy amounts of interference on a commonly used channel by Wi-Fi, then the design can avoid using this channel.

Most importantly: with Wi-Fi it is all about the client.  If the technology the client is using to connect to the wireless infrastructure is poor, then the experience will be poor.  No matter how good the wireless system.  If you have a mixed bag of client devices, old and new, fast and slow; all of this will affect the design.

So tell us what you want.  What you really, really want.