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We all start at Square One

June 19, 2014 at 10:00 am PST

I’ve been thinking about what to write for a while now.  I’m involved in some really cool projects right now, pervasive wifi in a theme park, using CMX with many zones at that same theme park and upgrading some public schools to newer equipment with full coverage wifi in the classrooms.  I think each of those would make a great post and I plan to touch on them soon, but this post will be on a comment that an intern made to me while we were upgrading a school recently.  “I can’t believe a Sr. Network Engineer is helping me cable a rack.”  I didn’t think much of it at the time but I did start thinking about it on the way home. Read More »

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The “Next Gen” Network Engineer

A subject very close to my heart at the moment is what skills I will need to have in order to support the Next Generation of Software Defined and Application Centric networks.

It is of no surprise that Networking like most other towers in IT has embraced abstraction as the way forward to provide levels of flexibility and agility never before seen in the Network.

What is perhaps a bit of a surprise, is the speed in which these new concepts are being developed and deployed. It seems like only last year terms like SDN were still viewed as “Way down the line” technologies. But here we are at the start of Q2 2014 and it seems like if you don’t already have an SDN plan you’re already behind.

So what skills will we need in order to design, support and deploy these new networks? Read More »

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Guest Blog: Migrating High Density University Networks to 802.11ac

Editor’s Note: This is a guest post by Joe Rogers, Associate Director of Network Engineering for the University of South Florida (USF). Hear Joe speak about his experiences with next-generation wireless in high density environments on next Tuesday’s webinar:  ”Migrating Enterprise Networks to 802.11ac” at 10am PST (Dec 17) (Register here)

Joe RogersJoe Rogers is the Associate Director of Network Engineering for the University of South Florida.  He is a graduate of USF’s Computer Science and Engineering program and has worked as a network engineer at USF for the past 20 years.  He is currently responsible for all aspects of USF’s network which provides connectivity to over 100k devices across three campuses.  He’s held a CCIE routing and switching certification since 1999.  When not working, he’s an avid mountain biker (if you can call it “mountain” biking when you live in Florida).

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Universities face some of the most complex design challenges in wireless networking.  Our user population is highly mobile, bandwidth-hungry, and often simultaneously using at least two wireless devices in rooms with hundreds of their classmates.  The wireless network isn’t simply a convenience to them.  It’s critical to their educational success as many of the students are taking tests or working on assignments across the network.

At the University of South Florida, we support over 20,000 concurrent wireless users on our network of over 4,000 access points.  We have more than 90,000 unique devices registered this semester.  Our biggest challenge is designing the wireless network for the device densities in our large classrooms and popular study areas.  In these locations, we often have a thousand devices in a few hundred square feet of space.

We heavily rely on band select to place as many devices as possible on 5Ghz where more channels are available.  Unfortunately many devices such as older tablets and smart phones simply don’t have an 802.11a/n radio.  So we must carefully RF engineer the environment with smaller cells to provide the necessary coverage density. Read More »

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Deploying, Testing, and Tuning 802.11ac

By now you’ve probably heard quite a bit about the newest generation of Wi-Fi, 802.11ac.  I’ll save you the gory details, just know it’s about 3x faster than 802.11n and will help to improve the capacity of your network. Jameson Blandford and I were recently guests on the No Strings Attached Show podcast with Blake Krone and Samuel Clements (Click to listen to the podcast).

I wanted to follow up the podcast with a blog to go over considerations for deploying, testing, and tuning 802.11ac.

Considerations for deploying 802.11ac

Switching infrastructure

The first question you’ll want to ask yourself, is, if your switching infrastructure can handle 11ac?  The answer probably is, yes.  The things to consider are the port speed and power-over-Ethernet (PoE) capabilities.  You’ll want the access point to have a gigabit uplink to the switch.  Each 11ac access point could potentially dump several hundred megabits per second of traffic onto your wired network.  It’s also not a bad idea to have 10 Gig uplinks on your access switches to distribution or your core.  If you have even just a couple access points on a single access switch, you may quickly find yourself wishing you had 10 Gig uplinks.

Next you’ll need to consider how you will power the access points.  If you are like the majority of our customers, you will use PoE from your switches.  While 11ac access points require 802.3at (PoE+) for full functionality, the Aironet 3700 will run happily on standard 802.3af PoE.  In fact, it remains 3 spatial-streams on both radios, so performance does not suffer because you have a PoE infrastructure.

Will you deploy 80 MHz channels? Read More »

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