Categories
Tech Thoughts

Energy Conversion Starts Making Sense

I just came to realize that my most hated subject at the moment, EE204: Energy Conversion,[1] in which I have flunked my exams 2 out of 2, would be useful to me as an aspiring Electronics Engineer. At first, as an ECE student, I thought I’m not going to need this course since I’m not planning to specialize in electric power generation that EEs should be doing.

While browsing through blogs and tech news sites like I usually do, I’ve read about emerging technologies that deals with the use of hand cranks and similar manually-operated power generators, instead of the conventional way of plugging devices onto a power outlet. I’ve also read about environmental issues concerning electric power consumption and conservation with computer and even search engine usage.

We still haven’t gone to discuss DC generators as we are just halfway through the course. But, seeing how the OLPC plans to make human-powered laptop computers by means of a crank, a pedal or a pull-cord in the form of XO-1 to be distributed to children on developing countries who have little access to electricity, I got the insight. Furthermore, I just saw a portable media player utilizing the same idea, thanks to Bernie of Talkin’ Tech.

I know I shouldn’t have been posting this now as our preliminary exam week is just a day away, and the exam on EE204 is first on the list. I am just happy to see current applications of what I am studying theoretically as it gives me more understanding of the subject matter.

So, let me just ask, what would you say about manually-powered electronic devices that use less power than conventional ones? Would you be seen using it in the future or you would just stick to conventional devices until none of them exists anymore? Hand cranks and pedal generators on the nearest Wi-Fi–enabled coffee shop, anyone?

Footnote:

  1. ^ a course dealing with the conversion of mechanical energy to electrical energy (as with generators) and vice versa (as with motors)
Categories
Attacks Tech

The Basics of Wireless Security

Wireless connectivity is probably best described to give convenience to its users. Having a wireless access point on your home gives you the comfort to position yourself almost anywhere provided your devices are within the range of each other—on your living room, on your bedroom, and even on the kitchen. There are still many concerns about having this type of connection, however, and most of them is about security.

Since laptops, smartphones and PDAs, provide for the needs of busy mobile consumers,[1] and most of them gadgets are now being equipped with Wi-Fi, it has no doubt become the next big target of crackers—much like what happened to Microsoft Windows being targeted on exploits and vulnerabilities, and to bluetooth-enabled mobile phones being targeted with worms and malware when they became popular.

Common things done by crackers to wireless-enabled devices and networks include piggybacking, wardriving, man-in-the-middle attacks, and spying, among others. Explanations are as follows:

  • Piggybacking refers to the act of obtaining access to resources on a wireless device, which include Internet access. Open networks on public places and services, such as hotels and cafés, usually permit this,[2] but some networks even on the said places[3] as well as on homes generally do not.
  • Wardriving is the act of looking for wireless networks usually with the aid of a vehicle,[4] and a powerful antenna on a wireless-capable device, much like what people with radio scanners do to receive police and military transmissions. After connection with the device has been established, the wardriver could possibly do anything to the network or its users. Some has been ethical, however, and act as a tiger team telling the administrator or owner that the network could easily be breached.
  • Man-in-the-middle attacks are somehow sophisticated that includes a cracker acting as the network access point the victims are trying to connect to. He then connects to the real AP himself transmitting and receiving data both ways to seem invisible. But, in fact, he now controls and sees every bit of information the victims are sending and receiving that seem to them to be secure.
  • Spying has been the most critical and publicized problem existing today—even surpassing the popularity of virus and worm attacks today, IMO. Anti-spyware tools just popped up one after the other from nowhere, haven’t they? And we thought it would have ended with just Web browsing with credit card information, but it obviously haven’t.

Wired LANs probably seem more secure since the only ones receiving data are the ones connected by wire—of which the owners control—while WLANs have access points and terminals that emit signals that could be received by anyone near the devices. However, this concept is somehow wrong. Wired networks with terminals having an active insecure Wi-Fi device could be entered by these crackers to gain access onto the network as well—much like providing the cracker a jack to plug into.

Having set up a wireless network at home myself, and after trying to configure each and every option presented to me by my router’s Web interface, I’ve searched through forums, blogs and info sites to find ways of maintaining my network security. Here are some basic instructions:

  • Wi-Fi Protected Access (WPA or WPA2) is the secure authentication and encryption method for wireless networks and should always be enabled. Most consumer wireless devices are capable of using at least WPA and WEP (an earlier security method that has known limitations). But, try to utilize WPA2 first, if it is available. It is an implementation of the IEEE 802.11i standard, and WPA is just its subset.
  • MAC address filtering is a feature from routers and access points that permits or blocks certain devices based on the hardware-embedded MAC addresses on their network adapters. Some NICs allow changing the MAC address to match an accepted one, also known as spoofing, so this should not be the only security measure utilized.
  • Change the router’s default settings such as Web interface password, SSID, and IP address. These settings are known by crackers and would immediately tell them if the user has an insecure network. These changes would at least make it harder for the cracker to find the network configuration and administration interface.
  • Most routers come with a hardware firewall that blocks potentially malicious and corrupted signals. This should never be turned off.
  • DMZ forwards all ports to a terminal so that all connections may pass. This is usually used for applications where the user does not know which ports are being used. The Port Forwarding feature, which is as common as DMZ, is more secure since it only forwards the applications’ required ports. Ask support from the application developers to know which ports should be forwarded, and avoid using DMZ.

There are many more types of security concerns and prevention, but these are the most common ones. Please note that until Windows Vista, Microsoft OSs have not supported an implementation of WPA2. But, a WPA2 update for genuine users of Windows XP SP2 is available for free download. After installing the update, an option to turn off broadcasting of the preferred wireless network list will be available and this would add to security.

I wasn’t able to test Linux wireless security as I have Ubuntu only on my desktop, which is on a wired connection. You may (and please) reply if you have information about wireless security in these and other operating systems. Thank you.

One very important rule to security in any digital environment is strong passwords. Choose them wisely; they should not be any dictionary word or phrase, at least one character must not be a lowercase letter, and you should not use one password on every digital account you use.

Footnotes:

  1. ^ Who are now practically everywhere—students, business people, posers, and everyone else who just have the money.
  2. ^ And are probably not considered as such act.
  3. ^ Where access is restricted to clients and customers only.
  4. ^ The term is usually used on the act using motor vehicles, while warbiking and warwalking are used to refer to wardriving on motorcycles or bicycles, and wardriving on foot, respectively.
Categories
Experiences School Tech

Scrap Metal

One day, I thought I heard a distant explosion—one you could think of as a failing transformer on an outdoor electrical post. My computer’s power flickered but It came back just nanoseconds later. But I was wrong. My computer wouldn’t turn on anymore. I realized what I heard was a discreet boom from the power supply.

My whitebox computer exploded Monday last week as I was about to print a document for our Electronics I report. It felt like the sky fell on top of my head. Panic struck me, though I came up with a way to retrieve the data. Besides, only the power supply really blew up. I just removed the hard disk drive from the system unit and plugged it into the external hard disk enclosure bought with our 250-gigabyte hard disk. I made a mess in my room trying to fix things. But, I wasn’t able to print it right away as our notebook doesn’t have a parallel port. Oh well, at least the data wasn’t lost.

My uncle gave [or lent] me a spare power supply unit from an unused computer to replace that scrap metal I had been using since 2002. I’ve just finished replacing it yesterday along with a busted floppy disk drive and the much larger hard disk drive [the one bought with the enclosure]. I could really describe my computer as katay, which is Tagalog for butchered—a rather exaggerated term for something taken apart [then replaced] piece by piece.

If you could remember my past article, my desktop computer had its motherboard and CPU replaced. Now, I’ve just replaced the power supply, hard disk drive and floppy disk drive. Hmmm … I wonder when I could build my own computer from scratch with new parts.

Easy answer: Not today. *tee-hee*