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Two Resources on Nexus Programmability

April 28, 2014 at 4:50 pm PST
Class is in session

Class is in session

As I start to explore more and more information about Software-Defined Networking and Programmability in the Nexus portfolio, I’ve been fortunate that there have been a lot of people helping me learn along the way.  I thought I’d share some of these as it gave me a bit more insight into some of the more holistic perspectives that I’ve been trying to get my head wrapped around lately.

I’m still starting off at a rather high level, though I’m spending more and more time getting deeper into the tech. Every once in a while, though, I need to look up and make sure that I’m swimming in the right direction. It’s really easy to get mired in the details and forget the bigger picture. Read More »

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#EngineersUnplugged S5|Ep2: ACI and Traditional Networking

March 12, 2014 at 10:53 am PST

This is an amazing episode of Engineers Unplugged, where two technologists from the community, Hal Rottenberg (@halr9000) and Colin Lynch (@ucsguru) discuss how ACI disrupts traditional networking thinking while leveraging current networking skills. It’s a great tutorial for anyone looking to understand what application centric infrastructure really means.

Will network engineers all become programmers?

Watch and see:

This unicorn comes with birthday wishes--Happy 5th Birthday UCS!

Happy Birthday UCS Unicorn courtesy of Colin Lynch, with commentary by Hal Rottenberg!

Happy Birthday UCS Unicorn courtesy of Colin Lynch, with commentary by Hal Rottenberg!

**The next Engineers Unplugged shoot is at Varrow Madness, Charlotte, NC, March 20, 2014! Contact me now to become internet famous.**

This is Engineers Unplugged, where technologists talk to each other the way they know best, with a whiteboard. The rules are simple:

  1. Episodes will publish weekly (or as close to it as we can manage)
  2. Subscribe to the podcast here: engineersunplugged.com
  3. Follow the #engineersunplugged conversation on Twitter
  4. Submit ideas for episodes or volunteer to appear by Tweeting to @CommsNinja
  5. Practice drawing unicorns

Join the behind the scenes by liking Engineers Unplugged on Facebook.

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Programmability in Python: Confessions of a Networking Guy

I am not qualified to discuss it much, but can you guess what this does?

     ne = NetworkElement("172.16.66.1", "JasonsApp")
     conn = ne.connect("admin", "cisco", sc)
     intf1 = ne.get_interface_by_name("FastEthernet0/1")
     intf1.shut_down(1)
     sleep(5)
     intf1.shut_down(0)

 

If you guessed that it logs into a switch at 172.16.66.1 and disables interface F0/1 for 5 seconds and re-enables it, then you guessed right.

Let us talk a little about putting the “ability” in programmability.  Did I code in college? Yes. Was I good at it? Not really. Dijksta’s algorithm (the actual coding bit) drove me crazy, however, actually using and operating networks quickly became my cup of tea. I became a network geek. Subnets? Awesome! Cisco CLI? Sweet. Using Enhanced Interior Gateway Routing Protocol (EIGRP)? Yay! AVVID? Even better. But I never wanted to see C++ or another “program” again.

Fast forward to 2014.  I’m still a networking guy but now I’m seeing code again.  The good news is, maybe like you, I hang out with some really cool people. I challenged a couple of them to help me demonstrate program “ability” to networking people on the show floor at CiscoLive Milan…with me as the test subject! Read More »

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HDX Blog Series #2: Scaling with Turbo Performance

Editor’s Note: This is the second of a four-part deep dive series into High Density Experience (HDX), Cisco’s latest solution suite designed for high density environments and next-generation wireless technologies. For more on Cisco HDX, visit www.cisco.com/go/80211ac.  Read part 1 here

With any new technology comes a new set of obstacles to overcome.  802.11ac is no exception.  Last week we talked about CleanAir for 802.11ac and why spectrum intelligence still matters. Another challenge is scalability. In this post I will give you some details on new HDX feature, Turbo Performance, which allows the AP 3700 overcome common scaling issues to scale amazingly well.

What’s Different with 802.11ac?

802.11ac means higher data rates, which means more packets per second (PPS).  There are three reasons for more PPS with 11ac: wider channels, increased modulation and increased aggregation.  Channel width doubled to 80 MHz, modulation increased from 64 QAM to 256 QAM, and aggregation increased from 64k to 1MB!

With 802.11n, an AP might have had to push 30,000 1500 byte packets per second through the APs data plane. Today with 802.11ac that could now be 75,000+ PPS.  More PPS means more load on the APs CPU, so to really keep up with the demands of 802.11ac, we needed to go back to the drawing board.   Read More »

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HDX Blog Series #1: Why Spectrum Intelligence Still Matters

Editor’s Note: This is the first of a four-part deep dive series into High Density Experience (HDX), Cisco’s latest solution suite designed for high density environments and next-generation wireless technologies. For more on Cisco HDX, visit www.cisco.com/go/80211ac

CleanAir for 802.11ac:  Why Spectrum Intelligence Still Matters

In wireless networking and communications, as with life, nothing good comes for free. It’s well known that the primary feature of the new IEEE 802.11ac amendment is support for an 80 MHz-wide channel. The benefit of an 80 MHz channel is the potential to double usable throughput in comparison to that of 802.11n using a 40 MHz wide channel.

However, what is less well known is that a wider RF channel is also more susceptible to interference. In other words, 802.11ac devices “hear more” than 802.11n devices, primarily due to the wider channel support. It should be noted that this is not a flaw in the 802.11ac amendment, it’s simply basic communications theory.

Nevertheless, there is far more to building an 802.11ac access point than simply meeting the standard. Not all 802.11ac access points perform equally without interference. But more importantly, not all 802.11ac access points perform well in the presence of interference.

Furthermore, there is far more to deploying High Density wireless LANs than only considering the performance of individual access points. Read More »

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