Tom Hollingsworth

Author Archives: Tom Hollingsworth

API-jinks

Dastardly-vi

Network programmability is a very hot topic.  Developers are looking to the future when REST APIs and Python replaces the traditional command line interface (CLI).  The ability to write programs to interface with the network and build on functionality is spurring people to integrate networking with DevOps.  But what happens if the foundation of the programmable network, the API, isn’t the rock we all hope it will be?

Shiny API People

APIs enable the world we live in today.  Whether you’re writing for POSIX or JSON or even the Microsoft Windows API, you’re interacting with software to accomplish a goal.  The ability to use these standard interfaces makes software predictable and repeatable.  Think of an API as interchangeable parts for software.  By giving developers a way to extract information or interact the same way every time, we can write applications that just work.

APIs are hard work though.  Writing and documenting those functions takes time and effort.  The API guidelines from Microsoft and Apple can be hundreds or even thousands of pages long depending on which parts you are looking at.  They can cover exciting features like media services or mundane options like buttons and toolbars.  But each of these Continue reading

The Atomic Weight of Policy

Helium-atom

The OpenDaylight project put out a new element this week with their Helium release.  The second release is usually the most important, as it shows that you have a real project on your hands and not just a bunch of people coding in the back room to no avail.  Not that something like that was going to happen to ODL.  The group of people involved in the project have the force of will to change the networking world.

Helium is already having an effect on the market.  Brocade announced their Vyatta Controller last week, which is based on Helium code.  Here’s a handy video as well.  The other thing that Helium has brought forth is the ongoing debate about network policy.  And I think that little gem is going to have more weight in the long run than anything else.

The Best Policy

Helium contains group-based policies for making groups of network objects talk to each other.  It’s a crucial step to bring ODL from an engineering hobby project to a full-fledged product that can be installed by someone that isn’t a code wizard.  That’s because most of the rest of the world, including IT people, don’t speak in specific Continue reading

An Educational SDN Use Case

During the VMUnderground Networking Panel, we had a great discussion about software defined networking (SDN) among other topics. Seems that SDN is a big unknown for many out there. One of the reasons for this is the lack of specific applications of the technology. OSPF and SQL are things that solve problems. Can the same be said of SDN? One specific question regarded how to use SDN in small-to-medium enterprise shops. I fired off an answer from my own experience:

Since then, I’ve had a few people using my example with regards to a great use case for SDN. I decided that I needed to develop it a bit more now that I’ve had time to think about it.

Schools are a great example of the kinds of “do more with less” organizations that are becoming more common. They have enterprise-class networks and needs and live off budgets that wouldn’t buy janitorial supplies. In fact, if it weren’t for E-Rate, most schools would have technology from the Stone Age. But all this new tech doesn’t help if you can’t find a way for it to be used to the fullest for the purposes of Continue reading

IPv6 and the VCR

IPv6 isn’t a fad.  It’s not a passing trend that will be gone tomorrow.  When Vint Cerf is on a nationally televised non-technical program talking about IPv6 that’s about as real as it’s going to get.  Add in the final depletion of IPv4 address space from the RIRs and you will see that IPv6 is a necessity.  Yet there are still people in tech that deny the increasing need for IPv6 awareness.  Those same people that say it’s not ready or that it costs too much.  It reminds me of a different argument.

IPvcr4

My house is full of technology.  Especially when it comes to movie watching.  I have DVRs for watching television, a Roku for other services, and apps on my tablet so the kids can watch media on demand.  I have a DVD player in almost every room of the house.  I also have a VCR.  It serves one purpose – to watch two movies that are only available on a video tape.  Those two movies are my wedding and the birth of my oldest son.

At first, the VCR stated connected to our television all the time.  We had some movies that we Continue reading

The Pain of Licensing

Frequent readers of my blog and Twitter stream may have noticed that I have a special loathing in my heart for licensing.  I’ve been subjected to some of the craziest runarounds because of licensing departments.  I’ve had to yell over the phone to get something taken care of.  I’ve had to produce paperwork so old it was yellowed at the edges.  Why does this have to be so hard?

Licensing is a feature tracking mechanism.  Manufacturers want to know what features you are using.  It comes back to tracking research and development.  A lot of time and effort goes into making the parts and pieces of a product.  Many different departments put work into something before it goes out the door.  Vendors need a way to track how popular a given feature might be to customers.  This allows them to know where to allocate budgets for the development of said features.

Some things are considered essential.  These core pieces are usually allocated to a team that gets the right funding no matter what.  Or the features are so mature that there really isn’t much that can be done to drive additional revenue from them.  When’s the Continue reading

I Can’t Drive 25G

Ethernet

The race to make things just a little bit faster in the networking world has heated up in recent weeks thanks to the formation of the 25Gig Ethernet Consortium.  Arista Networks, along with Mellanox, Google, Microsoft, and Broadcom, has decided that 40Gig Ethernet is too expensive for most data center applications.  Instead, they’re offering up an alternative in the 25Gig range.

This podcast with Greg Ferro (@EtherealMind) and Andrew Conry-Murray (@Interop_Andrew) does a great job of breaking down the technical details on the reasoning behind 25Gig Ethernet.  In short, the current 10Gig connection is made of four multiplexed 2.5Gig connections.  To get to 25Gig, all you need to do is over clock those connections a little.  That’s not unprecedented, as 40Gig Ethernet accomplishes this by over clocking them to 10Gig, albeit with different optics.  Aside from a technical merit badge, one has to ask themselves “Why?”

High Hopes

As always, money is the factor here.  The 25Gig Consortium is betting that you don’t like paying a lot of money for your 40Gig optics.  They want to offer an alternative that is faster than 10Gig but cheaper than the next standard step up.  By giving you a cheaper option Continue reading

Security Dessert Models

MMCOOKIE

I had the good fortune last week to read a great post from Maish Saidel-Keesing (@MaishSK) that discussed security models in relation to candy.  It reminded me that I’ve been wanting to discuss security models in relation to desserts.  And since Maish got me hungry for a Snicker’s bar, I decided to lay out my ideas.

When we look at traditional security models of the past, everything looks similar to creme brûlée.  The perimeter is very crunchy, but it protects a soft interior.  This is the predominant model of the world where the “bad guys” all live outside of your network.  It works when you know where your threats are located.  This model is still in use today where companies explicitly trust their user base.

The creme brûlée model doesn’t work when you have large numbers of guest users or BYOD-enabled users.  If one of them brings in something that escapes into the network, there’s nothing to stop it from wreaking havoc everywhere.  In the past, this has caused massive virus outbreaks and penetrations from things like malicious USB sticks in the parking lot being activated on “trusted” computers internally.

A Slice Of Pie

A more modern security Continue reading