Email and Forum Questions
- Email from Leslie in Fairfax: I am going to travel overseas and have heard that Viber is a good way to call using VoIP. I am confused. Can you compare Viber and Skype? Thanks, Leslie
- Tech Talk Responds: Both Skype and Viber have Android and iPhone application. They both are VoIP applications that use your handset data. Skype has long been synonymous with online calls since it was first launched on desktop computers. Skype has great voice quality during Wi-Fi or 3G calls. Video calling, the feature that separates Skype from other VoIP apps, was pretty excellent.
- Skype requires a user name and account which is different than your cell phone number. You cannot receive a Skype call unless you application is open and running in the background.
- Viber is the new kid on the block, released about a year ago. It is exclusively mobile to mobile, so you user name is simply you phone number. It verifies you number by sending you a text message with a verification number. It has a very simple and compelling interface. It does not support video at this time, but does support free text messaging. You can receive a call on Viber without opening the application, making it very convenient. The voice quality is not as good a Skype.
- When you have registered your phone number, Viber to automatically sync with your address book and indicate who of your contacts has Viber. When you receive a call or text through Viber, you get a pop up message. I will probably use Skype on my iPad and Viber on my cell phone.
- Email from John in Texas: I would like to use my iPhone for navigation. My friends have Androids and all enjoy turn-by-turn navigation. However, the iPhone Maps application will only give driving directions, but not turn-by-turn audio directions. Love the show, John.
- Tech Talk Responds: As you know, Apple refused to implement turn-by-turn voice navigation using the Google mapping backend which is native for all iPhones through 4S. They did not want to make Google technology too central. Thus only the Android sported this feature. It will be native in the iPhone once iOS6 is released with Apples own mapping service. Until then, you can use the MapQuest application for navigation. On my recent trip to Colorado, I took my TomTom Navigation system and compared it with MapQuest. MapQuest was excellent on the iPhone. I highly recommend it. The app is free and supported by ads. It is an AOL product.
- Email from Listener in Boston: Dear Tech Talk, I recently wrote an email from my Yahoo email account and sent to the wrong email address in Europe. Is it any way that I can retrieve the email I sent from the wrong email address and delete it before the wrong recipient can read my email? Thanks.
- Tech Talk Responds: The short answer is no. When you send an email, it normally travels servers which are not under your control. You can’t get the email back without their cooperation. Once an email leaves your outbox, you lose all control over it.
- In the case of Gmail, there is an unsend button available for a few seconds prior to the email actually being sent. If the sender and receiver are both on the same corporate email system, you may have an unsend option. Or you may request IT to delete the message for you. You only option is to send a Recall email. The moral of the story is double check your email before hitting the send button.
- Email from Alex: Dear Dr. Shurtz, I get a pretty good download speed of around 12mb/s. Yet when I go to download for example, a 12 MB file, why does it take so much longer than just a second? I am confused. Thanks for the show. Alex.
- Tech Talk Responds: The speed that your internet connection is measured in is in megabits per second. 12 Mbs (usually lower case “b”) is a 14-megabit connection. The file that you’re downloading is a 14-MB file (“megabyte”, normally that’s with an uppercase “B”). The difference, of course, is a factor of eight. There are 8 bits to a byte and thus, one would expect a 14 megabyte file to take eight times longer than downloading 14 megabits.
- But it will probably be longer than 8 seconds because there is overhead in any packet switching network (error checks, source address, destination address, sequence numbers, etc.) These are contained in header and footers on each packet. You should be happy with 80% of the actual speed of the connection. If there is network congestion, it will be slower.
- You can check your upload and download speed by going to www.speedtest.net. I have Verizon FIOS and tested my connection this morning with 20Mb/s download and 16 Mb/s upload. It may change during peak hours.
Profiles in IT: Ren Ng
- Ren Ng is the founder of Lytro and the creator of the first commercially available digital light field camera, a concept which will revolutionize digital photography.
- Ren Ng, 32, was born in Malaysia on September 21, 1979.
- His family immigrated to Melbourne, Australia when he was nine years old.
- As a kid, he liked painting, calligraphy, gymnastics, the viola—and, of course, photography.
- His first digital camera was a Nikon D100, and though he carried around a box of film in his refrigerator for several years, he never went back to film.
- He moved to California in 1997 to attend Stanford University, where he studied mathematical and computational science and dreamed of becoming a professor.
- In 2001, he earned a BS from, followed by an MS in 2002 and a PhD in 2006.
- While in school, he and his rock-climbing buddies became infatuated with photography. The blurry photos from those climbing trips to Yosemite and Lake Tahoe got Ng thinking there must be a better way to freeze time.
- Ren was a PhD candidate at Stanford researching light fields for his dissertation, and began to ask himself why focus is fixed in photographs, and whether it needs to be that way.
- One of his professors, Mark Horowitz, urged him to build a prototype. He raised capital to buy a $20K medium format camera.
- He took the camera apart, incorporated the microlenses in front of the main sensor in the camera to be able to capture light fields, and then put the camera back together.
- He had succeeded in coming up with a way of shrinking the Stanford Multi-Camera Array, consisting on 100 cameras, into a single camera.
- He finished prototype for his dissertation in 2004 and completed his dissertation, Digital Light Field Photography, in 2006, the same year he founded Refocus Imaging, Inc.
- His thesis earned the ACM Doctoral Dissertation Award for best thesis in computer science and engineering, and the Arthur Samuel Award for best Ph.D. dissertation.
- Lytro has raised $50 million in funding, most recently in a Series C round led by Andreessen Horowitz.
- Early investors include Intuit’s Scott Cook, VMware’s Diane Greene and venture capitalist Charles Chi, who was named interim CEO June 2012.
- Ng remained a full-time employee, but will shift his focus to product development.
- The Lytro Camera, available in February 2012, sold for $399, is the first commercially available camera to employ light field photography.
- Its lens actually consists of thousands of microlenses, each of which captures a slightly different slice of light.
- One shutter-snap records so much information that a user can readjust the photo after it’s been shot, such as shifting the focus from foreground to background.
- Lytro will ultimately license the technology and seek complete penetration of the high-end smartphones market.
- Hollywood studios have asked how Lytro could be applied to moviemaking.
- Link to dissertation: http://www.lytro.com/renng-thesis.pdf
- Company website: www.lytro.com
Amazon Cloud Affected by Power Outage
- Amazon has published a more detailed explanation about the outage that knocked out a number of popular websites last Friday night, including Netflix, Instagram, and Pinterest.
- The cause was a 20-minute power outage at a single Northern Virginia data center.
- Problems started at 7:24 p.m. PDT when there was a “large voltage spike” on the grid used by two of Amazon’s data centers.
- When technicians tried to move to backup power, the diesel-powered generators just didn’t work properly at one of the data centers.
- The generators started successfully, but each generator independently failed to provide stable voltage as they were brought into service.”
- The generators may have been powering up, but the switching equipment at the data center didn’t think they were ready for a switchover.
- Then, to confuse matters more, the power went back on for a few minutes and then failed again, just three minutes before 8 p.m. Seven minutes later, the data center’s battery backups started to fail. Then the data center went dark.
- It turns out that an abrupt power outage like that is pretty bad for the cloud. Though the backup generators finally started to restore power just 10 minutes into this second outage (power was fully restored 10 minutes after that), Amazon technicians soon discovered that it was going to take them about three hours to reboot affected servers in the data center and that this delay would be compounded by several bugs in their cloud software that they hadn’t known about.
- A bug in their Elastic Load Balancers (ELB) software — which customers use to spread internet traffic across different Amazon data centers — caused this important service to get overwhelmed across Amazon.
- This was the worst possible time for this service to go down, because customers whose programs ran in the downed data center needed this service to redirect internet traffic.
- ELB fell increasingly behind in processing these requests; and pretty soon, these requests started taking a very long time to complete.
- Another bug in Amazon’s Relational Database Service kept a “small number” of databases from recovering properly from the power outage.
- Amazon technicians were able to get things up and running for these customers only when they manually restarted the failover systems.
- Amazon is working to convince customers that it can do a better job of keeping servers up and running.
- The failing generators had been tested just six weeks previously, but now Amazon says its going to repair and retest the equipment — and replace it if it’s not up to snuff.
Facebook Security Check
- Facebook’s default security settings make your profile information available for anyone to search and allow every other Facebook user to contact you.
- To open Facebook’s privacy options, click Home in the top-right corner of any Facebook page and choose Privacy Settings. Three big buttons are labeled Public, Friends, and Custom. The audience selector is shown as a lock on the iPhone Facebook app and as a gear in the service’s iPad app.
- To prevent total strangers from reaching out to you on Facebook, click Edit Settings to the right of How You Connect. By default Facebook allows everyone to look you up by profile name, e-mail, and phone number, and to send you messages and friend requests. To restrict contacts, change the settings to Friends or Friends of Friends.
- Whether you share your Facebook information with everyone or only friends, it’s a good idea to know exactly what you’re sharing. The only way to know is to view your public profile. To do so, go to your profile page by clicking your name at the top of the screen, and then click View As.
- To change what’s on view in your profile, return to the Privacy Settings and click Edit Settings to the right of Profile and Tagging. You can share posts with everyone or just friends. More options are available for who can see what others post to your profile and posts you’re tagged in.
- Even if you share only with Friends, Facebook defaults to allowing the friends of the people you tag in a post or photo to view it as well. To prevent the friends of the people you tag from seeing the posts or photos, choose Custom in the drop-down menu next to “Who can see what others post…” and “Who can see posts you’ve been tagged in….” In the Custom Privacy window, uncheck “Friends of those tagged” and click Save Changes.
- The last three categories on the Privacy Settings page let you manage ads, apps, and sites; block access to your past posts; and block specific people and apps. The first blocking option converts all posts you’ve shared with the public and friends of friends to friends only (with the exception noted above for friends of the people you’ve tagged). To block a person, click Manage Blocking and enter their name or e-mail address. You can also block app and event invitations from specific people or add them to your restricted list, which shows them only the posts you designate as public. The last setting allows you to prevent an app from contacting you or getting non-public information from you.
SQL injection attacks up 69%
- SQL injection attacks are becoming significantly more popular amongst hackers, according to recent data.
- Between Q1 2012 and Q2 2012, there has been an estimated 69 percent increase of this attack type.
- The latest numbers come from secure cloud hosting company FireHost, which blocks various types of attacks that are attempting to harm its clients’ Web applications and databases hosted at the firm’s U.S. and European data centers.
- The company has broken down its findings into four different attack types which it considers as being the most malicious and dangerous: Cross-site Scripting (XSS), Directory Traversals, SQL Injections, and Cross-site Request Forgery (CSRF).
- Firehost has seen a rise from 277,770 blocked SQL injection attacks in the first quarter to 469,983 in the second quarter.
- SQL injection involves the entering of malicious commands into URLs and text fields on vulnerable websites. The goal is to steal the contents of databases and then use that information for further crime.
- SQL injection attacks have been associated with many high profile data breaches, such as when LulzSec hacked Sony in 2011. The data is from this year, however, so what gives? Well, the method is also often used by hackers to steal user account credentials such as e-mail addresses and passwords.
- SQL injection attacks are often automated and many website owners may be blissfully unaware that their data could actively be at risk. These attacks can be detected and businesses should be taking basic and blanket steps to block attempted SQL Injection.
Yahoo hack: Most Popular Passwords
- 442,773 Yahoo passwords were compromised.
- 342,478 of them were unique and only used by one person.
- 100,295 passwords, or 22.65 percent of the total, were used by more than one person.
- Here are the top 10 passwords from the Yahoo hack:
- 123456 = 1666 (0.38%)
- password = 780 (0.18%)
- welcome = 436 (0.1%)
- ninja = 333 (0.08%)
- abc123 = 250 (0.06%)
- 123456789 = 222 (0.05%)
- 12345678 = 208 (0.05%)
- sunshine = 205 (0.05%)
- princess = 202 (0.05%)
- qwerty = 172 (0.04%)