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Wednesday, December 31, 2014

10 Deadly Interview Questions

If you are like most managers, interviewing is not your favourite task in the world. As a result, many managers avoid the topic. Yet, for something people dislike so much, it is one of the most important tasks a manager must execute. Hiring great people is critical to a company’s success. In a survey, Grant Thornton reviewed 1000 companies in the UK and found companies with the highest growth placed ‘having the best people’ as the most important factor contributing to their company’s growth.
Even more surprising is that in another study, only 8% of corporations in the US have any formal interview training program for hiring managers. When was the last time you had interview training from HR?  Since hiring is a task that comes around infrequently, once or twice every six months for most managers, there is little motivation to invest the time in training.

In absence of formal training the one thing we suggest you can do to improve your interviewing skill is: prepare. Spend 15 minutes before the meeting reviewing the job description, jotting down some questions to ask, and think about what information you need that is not in the resume. Interviewing can be easier than you think but like every successful meeting, it all starts with a well orchestrated plan. And if nothing else, please at least read the resume before the interview.

Still need some help? Here are some interview questions that may give some inspiration to step up your interview game.

1. Tell me why I should not hire you.

Probably one of the toughest question to ask and slightly unfair.  Answers are ripe with pit holes and can really throw a candidate off.  This question is designed to test their ability to think on their feet. The best answers are ones that take an apparent negative and make it positive.  Recommended not to start your interview with this question.

2. Rate yourself on a scale of one to ten.

Yikes, who wants to answer this one? If you give yourself a 6, then you are showing a lack of self confidence and you may not be hired. On the other hand, if you think you’re a 10, you may be labelled as unmanageable and miserably egotistical. The safest response is middle ground, between 8 and 9. This says they are confident, capable, and hard-working, but they know there is always room for improvement.

3. Everyone takes home the occasional pen from the supply room. What is the most expensive thing you’ve taken?

This is a great question to challenge someone’s moral compass. What makes this a tough question is that it implies everyone steals from their employers and that it is okay to do so. A person must be confident enough to challenge the first statement. Since the interview is usually stressful many people will let their guard and reveal the craziest things. Make sure you preface the question with the question with the initial statement; otherwise you are just accusing some of stealing.

4. Tell me about your greatest error in judgment.

A nice question to determine if your candidate is a model employee or if they have the ability to do the job correctly. The story they choose to tell in response should be unrelated to their previous jobs and should have occurred sometime in the distant past. Also they must be able to talk how they have grown and learned from this mistake. Choosing something recent and/or work related may highlight weaknesses and indicate incompetence.

5. What did you tell your boss to get the time off to come to this interview?

Great question to start the interview. It may seem like an icebreaker question, but they are establishing they integrity. They either declare themselves a liar or said they had a doctor’s appointment. The only answer to this question is they are there on their own time, either using a vacation day or part of their lunch hour.

6. Your Manager gives you a large important project to complete by end of day and the President of the company asks you to clean up the office for an important client coming in. What do you do?

This question is less about the answer given and more about a person’s ability to make a decision they can justify.  It also gives insight to prioritization. The natural response for most people is to do as the president asks. The candidate will ask themselves ‘what answer does this person want to hear?’ It becomes a dilemma for the candidate. Asking more questions to better learn about the scenario is a good sign.

7. Tell me about a situation in which you would be willing to take a pay cut.

Another killer question. Are they a team player, would they take one for the team, or are they here only for the money? This question can lead to many responses, but use it to drill down to learn about their money motivations.

8. What is more important: money or time off?

A simple question, but one that will without fail stump many candidates. If they answer the question with money, it will seem greedy and that they will leave at the first job offer that pays higher. If they choose time off, then they may feel that they would be perceived as a slacker. This is a trap question.

9. Have you ever been fired from a job?

Direct question few people are willing to ask directly. Use it sparingly. If the answer yes, do not jump to any conclusions; investigate more. There may be a good reason.

10.  Tell me about the job you hated the most

Using this question is only effective if the interviewer spends some time understanding why and exploring what the person was doing. Dig deep on the specifics of the job duties. Do not take a one or two sentence answer.

Monday, December 29, 2014

2015: The year SDN and NFV go mainstream

In 2015, we expect to see organizations begin to take steps to truly embrace software defined networking (SDN) and its sibling – network functions virtualization (NFV). What other technologies and trends might we see in 2015?

Much of 2014 was spent discussing software-defined networking (SDN), network functions virtualization (NFV), and other “new” networking technologies. We also heard debates about the merits of the Internet of Things and what it will do for the world; we wondered whether the Apple Watch would drive an uptick in smart wearables. 2014 was, to an extent, the year of chatter.

We spent a lot of time defining SDN at forums and forming new standards bodies, but it was not uncommon to hear customers, media, and service providers ask for something tangible amid the discussion of its benefits. After all, where were the mass deployments?

In short, 2014 was the year we strategically moved pieces around the board, but never reached the point of calling “checkmate.”

So will 2015 offer more of the same, or will we see winners emerge and the new networking ecosystem take shape?

SDN and NFV to crack ground in the telecommunications market

It’s safe to say the SDN and NFV era is still in its infancy. That will soon change, according to Infonetics Research’s “2014 SDN Strategies: North American Enterprise” survey, which estimates that 87% of U.S. businesses intend to have SDN live in their data centers by 2016. From that perspective, SDN is well on its way.

These deployments have kept the hype somewhat subdued, but this is the most transformative technology we have developed in decades, and 10 years down the line – maybe even sooner – SDN will simply be known as “networking.” In 2015, the technology will begin the journey down that path with the first deployments of SDN in telco networks across the globe. This will be a huge step and could push SDN toward achieving critical mass; we expect to even see SDN deployed on global submarine networks to enable more dynamic services than anything available in the past.

We will also begin to see NFV become a technology du jour. There were NFV whispers in 2014, but 2015 promises to put the discussion on the map in the same way SDN was during the past 12 months. Once people see the tangible results of what software can do for a network, it’s only a matter of time before people begin to see the benefits of replacing hardware functions with virtualized equivalents. Infonetics research backs up these predictions in its “Carrier SDN and NFV Hardware and Software Market Size and Forecast” report, which predicts that the NFV and SDN markets will reach $11 billion globally in 2018. Along with the major telcos announcing SDN deployments, we’ll also see initial NFV deployments in high-touch enterprises.

Sunday, December 28, 2014

Time for an SDN Sequel? Scott Shenker Preaches SDN Version 2

Scott Shenker, one of the minds behind the creation of SDN, has some misgivings about the technology. It’s time for SDNv2, he says.

Speaking Wednesday at the Internet2 Technology Exchange conference in Indianapolis, Shenker explained that the first take on software-defined networking (SDN), which started taking form six to eight years ago, relied on some key “misconceptions.” That’s not an indictment of the SDN concept, just a sign that it could use some tweaking.

Shenker — who, along with Nick McKeown and Martin Casado at Stanford University, and others, developed OpenFlow and the ideas behind SDN in the mid/late 2000s — is working with other researchers (including McKeown again) on a set of technologies that he’s calling SDNv2, a second draft that takes into account Layer 4-7 equipment, the prevalence of virtual switching, and the rise of network functions virtualization (NFV).

But there’s an important caveat: SDNv2 targets carrier networks. They differ from data-center networks in that they’re filled with legacy equipment that won’t go away soon, and they’re equipped with a network core that’s built to forward packets quickly. His talk didn’t discuss the data center, where SDN-as-we-know-it might be working just fine.

At a time when we’re telling each other things are moving so fast, Shenker is disappointed that SDN has matured so slowly — more slowly than he expected, anyway.

The problem lies with SDN’s roots, he said. He and other researchers simply misunderstood the nature of carrier networks.

The Tenets of SDNv2

SDNv2 would still separate the control and data planes, and it would still aim for programmatic control of the network.

It differs from older SDN conceptions in three major ways (plus one more point of Shenker’s that I’m adding to this list). Keeping in mind that this is all about carrier networks, and not about settings such as Google data centers, those differences are:

1. Software goes to the edge; the core stays dumb. Implied in this statement: Switching at the edge becomes largely virtual, handled on x86 cores.

This can be done, Shenker insists. His calculations suggest that a major ISP’s traffic can be handled by $150,000 worth of x86 cores. (Other microprocessor architectures such as ARM‘s would be welcome here, of course, but Intel‘s x86 dominates the market.) Power consumption would increase compared with switch ASICs, but it would still be “infinitesimal” compared with the entire carrier network, he said.

Why is this different? Because Shenker and others started out assuming the network was homogeneous. The differences between core and edge switches — the existence of MPLS, essentially — wasn’t taken into account.

“This one is unforgivable. We just ignored current systems,” Shenker said. “One of the secrets, when you teach networking, [is that] nobody covers MPLS.”

2. “Middleboxes” get included in SDN. “Middleboxes” refers to the Layer 4-7 appliances, real or virtual, found all over the network.

SDN’s earliest incarnations didn’t take these into account, as Layer 4-7 vendors will tell you repeatedly. This was a shortcoming of the early jump to OpenFlow, which primarily manipulated Layer 2.

Under SDNv2, functions such as firewalls, load balancers, and WAN optimization would be included in the SDN edge, in virtual form. Sometimes they would be in the form of lookup tables, but more often, they would be virtualized network functions (VNFs) — which is where NFV gets folded into SDNv2.

This corrects the original SDN assumption that the data plane was dominated by routers and switches. In fact, Berkeley researchers including Sylvia Ratnasamy did a simple count of boxes and found carrier networks were just about evenly divided among routers, switches, and middleboxes.

“If SDN claims it is going to provide programmatic control over the network, then it has to incorporate these middleboxes,” Shenker said.

3. The network is opened up to third-party services. This is the biggie, and something that speaks to the purpose of SDN rather that the mechanics of it.

It means the edge of the carrier network would become analogous to Amazon Web Services: Anybody can check in, for a fee, and start using the network. Shenker calls this “service virtualization.”

It’s the crux of SDNv2, because it addresses carriers’ No. 1 problem: how to generate more revenues. New services are an obvious answer, but carriers are slow to develop new services and conservative about deploying them — and a service has to be a huge revenue generator, on paper, to even be considered.

By providing low-level interfaces into the network and a web-based, self-service portal, carriers could make money by having people pay to use the network as their own. Internet2 just announced a capability like this, in fact; its network virtualization lets any members take advantage of the 100-Gb/s Internet2 backbone.

Just as startups use AWS to avoid buying big chunks of computing power, they could use SDNv2 to rent out a carrier-sized network that they otherwise couldn’t afford. “If you had a setup like this, two kids in a garage could build a competitor to Akamai,” Shenker said.

4. Closed interfaces are not allowed. Shenker didn’t list this as an SDNv2 bullet point, but he was adamant about it later in his talk, and it seemed to resonate with the audience. “You do not have vendors offering vendor-specific interfaces at the edge,” he said — possibly a dig at Cisco‘s OpFlex, which became a multivendor effort but really did originate with Cisco.

SDNv2 Piece-Parts

Of course, Berkeley is working on a few elements to get all this done:

  • Recursive SDN, which combines the best aspects of SDN and of global networks. SDN is being used on tens of thousands of switches at a time — but they’re all in a data center, all in the same place. Global networks have a wider reach, by definition, but they lack the fast failure recovery that’s vital to packet processing. Recursive SDN applies programmatic control to the hierarchy of a global network, initiating local responses to failures and using network virtualization to create new paths.
  • The elastic switch (a name Shenker doesn’t like, but, too bad). This would be a self-managing group of equipment (not necessarily one switch) that sits at the edge and uses a combination of virtual switches and ASIC-based switching —because you’ll want both, Shenker said. The ASIC switches would be good for cases of fast-and-dumb forwarding that don’t need much packet processing.
  • Various packet-processing improvements, such as better methods for fault tolerance. Shenker didn’t have time to get into details.
  • Network verification for middleboxes. With routers, there’s a way to check if the routing tables are valid and don’t cause loops. Layer 4-7 equipment has no equivalent because they don’t operate on simple tables. They’re more like software programs, “and when you check collections of programs, you use model checking,” which really doesn’t scale, Shenker said. His team has found a framework that does work at scale, though; it can verify 35,000 middleboxes in five minutes, he said.

A Word About OpenFlow
So where does OpenFlow fit into all this?

OpenFlow itself isn’t a bad protocol, Shenker said. But OpenFlow was meant to communicate new ideas to networking equipment. The limitations of ASICs — table sizes, for instance — prevented OpenFlow from getting some of those ideas across.

“It’s not that the OpenFlow design is wrong. It’s that it was given an impossible task,” he said.

Shenker was also a founder of Nicira, a startup whose arc mirrors his misgivings about OpenFlow. Nicira began life as an OpenFlow startup but quickly shifted strategies toward network virtualization; it was famously acquired by VMware in 2012 and became the basis for the NSX product line.

Shenker thinks OpenFlow would eventually be a candidate to run SDNv2’s packet-forwarding core, but today’s MPLS would suffice for now.

Changing the Innovation Model

You can see how SDNv2 is tailored to the carriers, because it opens the door to new revenue sources without displacing the mass of legacy equipment that’s not going to be decommissioned any time soon. Specifically, the network core wouldn’t have to be touched at first.

But preserving the legacy network isn’t what SDNv2 is about, Shenker insisted. “Most importantly, this is about changing the innovation model” for SDN, he said.

So far, he’s not getting a good reception from the U.S. carriers, despite their need for new services. Foreign carriers have been more inviting, though, and he thinks that could spur some demand. “My guess is that once it gets deployed there, it will be much easier for American carriers to pick up,” he said.

Like the P4 protocol that could be a candidate for OpenFlow 2.0, SDNv2 is an academic exercise for now. But Shenker’s talk revealed ways to plug the gaps between the real world (especially the carrier reality) and SDN’s original assumptions. Even if SDNv2 doesn’t get off the ground, the points he brought up could prove valuable.

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