Saturday, October 10, 2015

010-151 Supporting Cisco Datacenter Networking Devices (DCTECH)


QUESTION 1
Which method is a TCP/IP-based protocol for establishing and managing connections between IPbased
storage devices, hosts, and clients?

A. FCIP
B. iFCP
C. iSCSI
D. FCoE

Answer: C

Explanation:


QUESTION 2
Which method does FCIP use to enable connectivity of geographically distributed Fibre Channel
SANs over IP?

A. routing
B. tunneling
C. handshaking
D. transporting

Answer: B

Explanation:


QUESTION 3
Which important feature on the front end is provided to the clients by multiple servers that access
the same storage devices across the SAN?

A. recovery
B. redundancy
C. resiliency
D. security
E. storage

Answer: B

Explanation:


QUESTION 4
The Ethernet specification details several different fiber optic media types. What is the wire
transmission speed for 100BASE-FX Ethernet?

A. 10 Mb/s
B. 100 Mb/s
C. 1000 Mb/s
D. 10000 Mb/s

Answer: B

Explanation:


QUESTION 5
Which fiber optic cable type is used most often with a Subscriber connector?

A. dual-mode
B. single-mode
C. straight-mode
D. multi-mode
E. subscriber-mode

Answer: B

Explanation:


Tuesday, September 8, 2015

The sharks of the Internet

That’s what hackers are — they should be feared, but our fears are completely out of proportion

My company’s CEO called me in a panic the other day.

“I think my iPhone may have been hacked,” he said, as I squinted myopically at the clock trying to see what time it was. 7:15 a.m. — time to get up anyway, I thought.

“What makes you think it’s been hacked?” I asked, trying to get my bearings. What day was today? I thought I had a meeting later that morning, but this was no time to get distracted, so I focused my attention on the CEO’s voice.

“It’s been getting really slow over the last week or two,” he said, “and sometimes it just freezes up.”

Well, that’s a sure sign of a hacker, I thought: a slow mobile device. I guess there must be armies of hackers all around us. I asked if there was any other strange behavior.

“No, but it worked fine before a couple weeks ago” he replied.
By now, I was fully awake and realizing I needed to get off this call and get to work. “Call the IT guy,” I said, “and have him troubleshoot the problem.” I told him I didn’t think it was a hack attack, just another glitch in the software. I hate to make assumptions, but this didn’t sound like the symptoms of a compromise. There are many possible causes for slowdowns and freezes, and at least on iPhones, hackers do not top the list — especially since I have many layers of security in place, including mobile device management (MDM), which gives me control over the device’s security settings, and application reputation monitoring, which alerts me if someone installs a dangerous app.

I found out later that the cause of the problem was an unreliable operating system release that had been installed on the CEO’s phone. That particular version had a known bug that caused it to run out of resources over time, slowing to a crawl and eventually freezing. My CEO was relieved that we weren’t under attack. I was left feeling puzzled and a little bit annoyed. I mean, it's hard enough to educate people at my office about real-world security threats and make them aware enough to avoid clicking dangerous links and attachments. Misconceptions and misplaced fears of Hollywood-style uber-hackers just get in the way and distract people like my CEO from what they should really be paying attention to.

Why in the world would anyone jump to the conclusion that unusual software behavior was being caused by hackers? How often do any of us actually get hacked? And when we do, is it that noticeable?

I think the answer is in fact no. Look at all the security breaches of the last 18 months — Target, Home Depot, Michaels and Chase, for example. How many of them were detected in progress? None. The victims were completely unaware they were being hacked, and the reason is that the hackers were subtle. I would think the victims would have been alerted if their computers started freezing up. When you're hacked, you don't see it while it's happening.

In fact, today’s hackers are very sophisticated. They exploit zero-day Adobe Flash vulnerabilities to invisibly install malware through malicious advertisements on websites, or poison Web searches to lure victims into malicious search results. The least sophisticated hackers still send old-fashioned email phishing scams, but even those install malware silently, without disruption.

I’ve also had several friends make the hacker assumption over the last several months. Anything strange or unusual seems to be caused by a malicious actor, in today’s common wisdom. I can’t help but scoff when I hear stories of phantom mouse movements (inevitably caused by rundown batteries in wireless mice), or phantom keystrokes (invariably the result of rundown batteries in wireless keyboards). Or even the dreaded (Microsoft Windows) Blue Screen of Death, which is always caused by instability in the operating system and its device drivers.

So why are people so quick to assume the worst-case scenario (a hacker did it) instead of the simplest explanation (the software isn’t perfect)? I imagine it’s because of two factors. One, they have seen too many news stories and movies where hackers are portrayed with magical, almost godlike powers of technological influence as they tap away at their keyboards. People just don’t understand the realities of software vulnerabilities and exploits. And two, I think the fear of hackers is akin to the terror of sharks. Because sharks are portrayed in movies and TV as vicious monsters, and most people don’t understand them, they are perceived as utterly terrifying. Never mind that you’re 20 times more likely to be killed by a cow than a shark, and nearly 60 times more likely to be killed by a bee. And we are all 33,000 times more likely to be killed by a car than a shark. It’s the shark we fear. We fear what we don’t understand, and what we see on TV. And to most people, hackers are unfathomable, dreadful apparitions that can strike at any time, with no warning, for no reason.

Should we fear hackers? Absolutely. But should we fear them unreasonably, without cause? I think not. Come on, people, get it together. We all need to develop a sense of perspective.