Monthly Archives: October 2009

Public Wireless Networks, How Secure Are They?

Computer Security,

In a nutshell: Not very. With portable computers being more and more popular, and wireless access in public places being found more and more often, this becomes a problem.

Let’s take a look. Public wireless networks (hotspots) like those found at airports, cafes, libraries, hotels, supermarkets, etc. lack encryption. What is encryption? basically the transforming of information using a special formula that is only decipherable by having a certain piece of information – a key. So your hotspot with no encryption looks like this:

laptop –> wireless receiver –> Internet

Nothing wrong with that, except the information is traveling from your laptop in the form of radio airwaves spreading in all directions in plain form and it’s therefore possible for a “sniffer” to intercept the data – an activity that has been given the name of “sidejacking”. And since there is no encryption, your data is open to view.

Let’s look at the same setup, but with encryption enabled:

laptop  –> (encryption) –> wireless receiver –> (decryption) –> Internet

Now the wireless aspect of the data transmission is protected by encryption, and is no longer available to sniffers who might want to access it. Of course strictly talking any encryption can be broken, but the difficulty to do it when using good encryption discourages most cyber-criminals as long as the target (you) doesn’t look too attractive, as I’ve explained in this earlier article.

So, what rules emerge from the above data? when using a public, non-encrypted hotspot to access the internet:

1) Do not enter passwords or supply other credentials in a website, unless the webpage itself is protected with encryption (in browsers like Internet Explorer or Mozilla Firefox you’ll see a lock in the lower right corner to symbolize encryption is being used in that web page, and typically the website address starts with “https://” instead of “http://” , signifying the page is secure). Even then and for reasons beyond the level and scope of this article this is not particularly recommended.

2) Avoid banking or doing online transactions, even in a secure webpage.

3) Basically, don’t do anything on your computer related to an internet connection you wouldn’t mind doing if you had a bunch of strangers right behind you looking at your screen and taking notes!

Wait until you get home (or to a secure wireless network)  to do any of that. And I surely hope you have encryption enabled at home if you connect wirelessly to the internet!

Hope this data helps.

Tips for Travelling with Laptops

Technical Tips,

An increasingly popular type of computer, laptops have seen a surge in demand over the last few years. Did you know that in 2008 and for the first time ever, the number of new laptops sold surpassed the number of new desktop computers sold? and now with the even lighter version of portable computers, the netbook, they are becoming more and more popular.

All trivia aside, since more and more people are jumping on the laptop bandwagon, I figured it’d be a good idea to write a couple of tips about how to go about them when one is on the go.

Since when you’re mobile you mostly depend on the laptop’s battery life, it’s a good idea to economize in what uses power the most. For example, if you are just using a word processor or watching a movie, you can turn off the wireless adapter. Also try to use a lower-than-maximum screen brightness when depending on battery power.

There are four main power states the laptop (or any computer for that matter) can be on. These are, in descending order when considering power consumption (1) Fully on, (2) Suspend/sleep, (3) Hibernation, (4) powered off. In sleep mode, several parts of the computer are turned off, but the computer is still capable of responding to user input, such as a key stroke or mouse click/motion. In hibernation, it’s a different story. All the running programs and opened files at the moment of starting hibernation are saved to the hard disk and the computer is effectively shut down. But while it is necessary to press the power button to resume normal operation, coming back from hibernation is much faster than starting the computer from scratch. This is therefore the preferred state in which a laptop should be transported – hibernating. The power consumption is at its minimum, the hard disk is not operating (important since moving a laptop around with its hard disk on can lead to damage to the hard disk) and yet turning it back on takes a minimum amount of time.

Since it is usual to close the lid of a laptop when carrying it around, you should know that what the laptop does when you close its lid is something you can change. The range of actions (when closing the lid) go from doing nothing, to putting the laptop to sleep, to hibernation, to shutting down. It is also possible to have different actions occur depending of whether or not the laptop is plugged in to a power supply when the lid closes. For example, you can set the laptop to go to sleep if the lid is closed when plugged in, but hibernate if the lid is closed when powered by the laptop’s battery.

One more thing you should also know in regards to the subject is about rechargeable batteries: They have a limited number of recharges before its ability to hold charge degrades.  After about the 60th recharge the battery will start to wear progressively and perceptibly, to the point where it holds only a few minutes worth of charge or no charge at all. So try to use the laptop’s battery power only when it’s needed.

Proper use of a laptop’s power settings will increase the time you can use it while on the go.

“Should I Turn Off my Computer at Night?”

Computer Security, Technical Tips

If I had a penny for every time I have been asked that question… I’d be writing this article from a bungalow in the Bahamas.

But I don’t. So, to the question at hand.

People in favor of turning the computer off at night bring up valid points, the main one being power consumption. But did you know that properly set power management settings reduces idle power consumption around 70%?

Others reason that with the computer off when not in use during the night the possibility of a hacker intrusion attack is reduced. True but if that is the concern, you can disconnect the computer from the internet (through disabling the network adapter, or a switch for many laptops with wireless, or disconnecting the network cable, or turning off the router, or…). And the truth is, it is relatively easy to repel hacker attacks if you have a sound computer security setup in place.

So now that we have those out of the way, let me tell you what is good about leaving your computer on at night.

There are several routines that traditionally computers are scheduled to perform after hours, when the computer is idle. These include: virus scans, hard disk defragmentation, system restore points, Windows updates, system backups, among others. When you turn your computer off at night, all these routines are not performed and to that degree your system is running in a non-optimum state.

And did you know that over time, it is more taxing for the electronic components of the computer to go from room temperature to operating temperature to room temperature to operating temperature than to remain in the same relative temperature range?

One last thing. Just about the only thing that is good about shutting your computer down at night and restarting it in the morning is that all memory errors and such are cleared up. The maxim “when in doubt, restart” applies here. So if you are one of those users that turned your computer off at night and decided to change to leaving it on, I recommend a restart at least every few days, to clear such errors accumulated over time. It will do for a smoother operating computer.

This subject has people that advocate for either of both possible answers and thus I expect some percentage of people to disagree with my position. If so it is your prerogative and I respect it. But the above is my take on the subject, based on over 25 years of experience with computers. Up to you to follow it or not.

Setting Up a Home Office

Technical Tips

A trend-in-the-rise in recent times, more and more people are starting businesses from home. Perhaps you and your spouse work together in the same business, from home. Regardless of what business category yours is in, it’s almost certain that part of the setup must include computer equipment. Permutations of the setup will depend on the type of business, but the basic elements are basically the same:

Small networks like a home network are usually setup as a workgroup. In this setup, there is no central computer and the existing computers are setup in a peer-to-peer networking setup. Yet with this setup printers and files can be shared between computers. Printers these days have multi-function capabilities, which means they can also send and receive faxes, something often needed in a home business setup. This function can also be shared among computers.

Normally this setup will have some sort of high-speed internet service, which typically goes modem–>router–>computer(s). Depending on how close the computers are to the router and whether or not it is therefore easy to do a wired networking setup, a wireless one can be done with relative ease. The wireless function can also include the printer if so desired.

Software installed in the computers will vary. But almost certainly you’ll have an email client program, some sort of accounting software for bookkeeping, and perhaps CRM (Customer Relationship Management) software to keep track of client prospects’ activities throughout the sales pipeline and to make sure the customer retention percentage remains high.

Investing the time in properly setting up your home business computer apparatus can help boost efficiency and thus productivity.

The Ultimate Malware Protection Tool for Web Surfing

Computer Security,

A few weeks ago I covered in an article the best protection model for a computer when it comes to malware. You can find that article here.

However, good as it might be, with the advances in malware technology there is still a chance your computer will get infected while browsing through websites, if you’re not careful.

For those who need and want ultimate protection while web surfing, the answer is virtualization. Simply put, virtualization in this context refers to the creation of a  separate operating space within your computer, which can then act as a sandbox. In other words, it’s like a computer within your computer. While not strictly correct, this is the easiest way to portray it for the non-advanced user. But the point is that while you are browsing, you can choose to turn virtualization on and thus everything that might impact your computer in terms of malware can be discarded at a press of a key once you finish your browsing session.

There are several programs that achieve this, perhaps the most known is Sandboxie, http://www.sandboxie.com/

Other programs have a built-in feature that can be used as a sandbox. For example, I use Acronis True Image Home 2009, a backup application. It has a function called “Try and Decide” which is simply an implementation of the mentioned virtualization function, with the same results.

So when is it recommended to use one of these programs? For example, if you are required to browse the web constantly and you often do searches and you are not sure of whether or not a malicious website might come up in the top search results, effectively infecting your computer when you click on that search result.

Virtualization or sandboxing is something that can be turned on or off selectively. In other words, you can have a sandboxing program installed and only use it when you deem it necessary.

And in some instances it can be proven to be very necessary.