Month: November 2014

  • OS X 10.10 Yosemite WiFi Problems Analyzed with Wireshark

    I never realized how often I google and how much I rely on sub-second response times until I upgraded my Macbook Pro to OS X Yosemite. After muddling through issues like upgrading VMWare and a few other items and fixing my terminal emulation, I couldn’t figure out why I was in such a bad mood.

    Then it hit me. My Google searches while I had been doing that had been slow. I would type something in and Google’s search results page either would not appear for about 3 to 6 seconds, or it would half-appear and then the search results would only show up after 3 to 6 seconds.

    There is so much garbage SEO bait out there about “what to do about Yosemite wifi problems” so I’m not going to bore you with the details of my investigation and I’m just going to cut straight to the chase:

    I put a network analyzer on my wifi. It turns out that the problem appears to be duplicate packets arriving on the WiFi network card. I switched to Ethernet via the Thunderbolt adapter and the problems instantly went away.

    Here’s what it looks like in Wireshark….

    Screen Shot 2014-11-13 at 2.21.31 PM

    What happens is the network card transmits an acknowledgement. Then there’s a 2.7 second freeze where nothing happens. And then a few packets arrive followed by a flood of duplicate packets.

    The duplicates are both duplicate application data packets along with duplicate TCP acknowledgements.

    Scrolling further down you can see the duplicates increase and Wireshark starts labeling them “TCP Spurious Retransmission”, implying an issue with a network interface on the network.

    Screen Shot 2014-11-13 at 2.23.50 PM

    Another test shows exactly the same thing. A 3.1 second delay where I’ve highlighted in blue and then a few good packets and the duplicates start.

    Screen Shot 2014-11-13 at 2.30.26 PM

    And then the frequency increases…

    Screen Shot 2014-11-13 at 2.31.38 PM

    Deleting and re-adding your wifi network or network card device does not fix this. Neither does some of the other suggestions out there like turning off bluetooth, joining a 2.4 Ghz network instead of 5Ghz, etc…etc..

    To me this seems to be a driver issue where the network card freezes and when it comes out of the freeze it’s sending the OS large numbers of duplicate packets. It’s curious that the freeze is around 3 seconds each time.

    This test was done on a: MacBook Pro (Retina, 15-inch, Early 2013). The only other software running while this test was being done was Chrome, Excel, X11, Wireshark, Terminal and Keyboard Maestro (a keyboard macro utility).

    Writing this post after the test was done on ethernet and I can feel my sanity already returning.

    Apple please fix. Thanks.

     

  • Startups that Move the Needle

    Something that I’m becoming more cognizant of and that I see in my friends as we all get a little older is the question about whether what we’re doing is actually moving the needle for the rest of humanity. If it’s making positive change by enabling our species or improving quality of life for others.

    My business is cybersecurity and the biggest positive impact I see is when we help mom and pop or small businesses keep their websites and businesses secure. But I question whether we can do more. I think Elon’s SpaceX and Tesla moves things forward for our species as a whole.

    An old friend arrived in Seattle this weekend. He has a really exciting startup based in Europe and is one of the most persuasive and energetic guys I know. It’s his second or third time in Seattle, ever – he doesn’t even live in this country – and  we show up at the Black Keys concert, sold out show on Saturday night at Key Arena, he walks up to security and talks us into a sold out show without any bribes or cash changing hands.

    So in between rocking out to Black Keys and then hitting a Bollywood party in Freemont, I learned about what he’s been doing for the last few years.

    Oradian creates software for banks in developing countries to do what banks do. Most of their target market is either using paper or using antiquated systems that are cobbled together and run on an old PC or laptop. Oradian provides a cloud based core banking system that gives banks a way to drop in an IT solution and get up and running fast.

    My first thought was skepticism that a bank in a developing country would have access to the Net. But Antonio has been on the ground selling directly into these organizations and markets for a few years (he was previously in micro-finance) and because of the heavy reliance on cellphones in these markets, the Internet is more reliable than the power grid.

    They’re currently raising series A in the USA and Europe and it’s interesting hearing his perspective and seeing other companies that are raising in Seattle and the Valley. I think there are other exciting businesses out there that are moving things forward, but there are so many that are spending precious energy on attracting a few more clicks or a few more eyeballs and I’m not sure how they help make the World a better place.

    It’s gotten me thinking about how we measure success and gauge whether something is a great idea or not. I’m not sure I’ve ever seen a startup appear on the West Coast that has a for-profit model that has the potential to make positive change in developing countries. I grew up in South Africa (as did Antonio, Oradian’s CEO) and we’ve seen and continue to see first hand how important it is to create a strong middle class in developing countries that is empowered with commercial opportunities and the services that surround them in the form of banking.

    I’d like to see more smart people thinking about this space and if Oradian is anything to go by, my sense is that there are opportunities in the developing World that can be both profitable for investors and make significant positive change.

    Edit: Found this video which gives you a better idea of what Oradian does…