Archives for November 2004 dunxd.com (4)

Surf better with a new browser

Categories: Articles
Comments: No Comments
Published on: November 27, 2004

When we use the internet and the World Wide Web we almost always use a web browser to access the information we seek. For many people their web browser is the most used programme on their computer. If you access the internet from
an internet café, web browsers might be the only programme you use.

Clearly web browsers are very important. Despite this, they are one piece of software we rarely think about. We don’t normally choose a browser as we might choose other important tools, such as a car or radio.

The reason we don’t make a conscious choice is that we almost always have a browser installed on our computer already. If you use Windows, and the vast majority of us do, the web browser called Internet Explorer is already there.

A similar situation exists for cars. When you buy a car it usually comes with a radio. For some people this radio is perfectly sufficient. For others the radio does not pick up their favourite station or doesn’t play cassettes or CDs or play loudly enough. Those people will get a new radio. You do not have to accept the choice that has been made for you by the car’s manufacturers. The same goes for browsers.

Firefox – free, open and secure

Firefox is a new web browser released earlier this month by the Mozilla organisation, an offshoot of the company Netscape, who produced one of the first web browsers.

Firefox is an open-source programme, meaning that, if you want to, you can look at the code that makes things happen, and even change that code if you see a way of doing something new or better. Internet Explorer is closed-source – you
are not allowed to see the code, so cannot see how the programme works or improve it.

For most people who do not know programming languages this is not obviously important. However, since Firefox is open-source, when a problem is discovered it can be fixed by anyone who has the knowledge, time and energy to do so,
not just employees of a single company. This means that security holes and bugs tend to be fixed more quickly in Firefox than Internet Explorer. Firefox is not as closely tied to Windows as Internet Explorer so any security holes that exist in it are less severe. This combined with its newness mean that currently Firefox is less of a target for hackers and spyware writers.

Extra features

The security and frequent updating of Firefox is of greatest concern for businesses that need to safeguard their data. For individuals Firefox’s extra features are a far more compelling reason to use it.

Tabbed browsing keeps all your Firefox windows together in one item, meaning less clutter on your taskbar.

Popup blocking prevents those incredibly annoying pop up adverts that have been the blight of the internet for many years.

Search makes it easy to find words on a web page taking you to the information you need faster. Just start typing the word and you will be taken to each occurrence.

Search bar builds search engines right into Firefox. Just type your search into the search bar, select an engine from the drop down menu and you will be taken straight to the results.

Password Management allows you to see a list of stored passwords as well as automatically enter them on pages you have to login to.

Extensions allow you to add new features to Firefox such as news feed readers (one called Habari Xenu), advert blocking, and download management.

Themes allow you to change the look of Firefox.

These features make your web browsing both richer and safer. If you care about using the web it is certainly worth considering Firefox.

Getting Firefox

Firefox can be downloaded for free from www.getfirefox.com. It is a 4.7Mb download, which is considerably smaller than updates to Internet Explorer.

Other choices

Firefox is just the newest browser available – there are other options for your web browser. Here are a few of them:

Mozilla is a full featured internet suite also produced by the Mozilla organisation. As well as a web browser Mozilla includes a full featured email programme with excellent junk mail filtering, and an HTML editor that makes it easy to create and edit your own web pages. Mozilla can be downloaded from www.mozilla.org/products/mozilla1.x.

Opera is a very compact browser that claims to be “the fastest on earth.” Surfing can be speeded up by easily turning off images and the way pages are lain out can be adjusted in a number of ways which make them easier to read. Opera is available from www.opera.com.

Lynx is a text only browser – it does not show any pictures. For those on very slow connections using Lynx will speed up access to web pages considerably, although pages that rely strongly on pictures will obviously not be very satisfying. Lynx can be downloaded from www.fdisk.com/doslynx/lynxport.htm.

Originally published in Arusha Times 348

Securing your email from prying eyes

Categories: Articles
Comments: No Comments
Published on: November 13, 2004

In the last InfoTech I introduced you to Cryptography – the art of encoding things so they cannot be read by strangers. This week’s article is a bit more practical. I will show you what you need to secure your own email, and prevent other people from sending emails in your name.

The Tools – Email Software

If you use email software like Outlook Express or Thunderbird securing your email is very simple. You must obtain what is known as a certificate – this allows you to digitally sign your mail with a public key. Recipients of such signed mail will then be able to store your signature and send you encrypted mail, which you decode with your private key. Free certificates can be requested from Thawte.

Do not do this in an internet café. This does not work for Hotmail or Yahoo users. See the end of this article for suggestions for users of Internet Cafes.

To register you must give some personal information – this includes a national identification number, such as found on your passport, drivers license or id card. You will also need to choose a password – make sure not to forget it, or make it too easy to guess. You must then select five security questions and give corresponding answers – these will be used if you forget your password. Once enrolled you can change the questions. After going through all this you will be sent an email with further instructions – this confirms that you are the person who collects email at the address you gave. Follow these instructions to complete your enrolment with Thawte.

Once enrolled you can request certificates. Login to your Thawte account at https://www.thawte.com/cgi/personal/contents.exe with your email address and password. This page allows you to request a new certificate – you can also add other email addresses (you must use a different certificate for each one). For now, click on the Request button. Follow the instructions and you will soon be sent an email. Click on the link in the email to install your certificate. Phew!

Signing mail

Now you are certified you can sign messages. In Outlook Express create a new email. Before sending it click on the Tools menu and select Digitally Sign. Send the email as normal. If you have received a signed message from someone else you will be able to send them encrypted messages by selecting Encrypt message in the Tools menu. Messages sent in this way cannot be read on transit, and only by the person with the original certificate/private key.

You will be warned if you receive a message that has been tampered with in any way, or if a message is signed with the wrong certificate. Since certificates are stored on the computer you use, it is not a good idea to set up email software for secure mail in an internet café – the next person would be able to sign emails and pretend to be you – isn’t it bad enough when you forget to sign out of Messenger and the next person fools your friend for a while?

Encryption for Internet Café Users

Unfortunately convenient secure email is not really available for those who do not have their own computer on which to store certificates. Two webmail providers, Hushmail and Cryptomail, offer secure email, but only between users of the same system (eg me@hushmail.com to you@hushmail.com.) If you feel the need to secure your email, you had better encourage your friends to get a free  account with one of these providers. Hushmail is the easiest to set up, while CryptoMail promises to allow secure email with users of some other systems in the near future.

Do you need encryption?

Most people do not currently feel the need to encrypt their email. However, with governments increasingly wanting to keep tabs on their citizens, and a huge rise in the number of hackers out there spying on our personal details I believe that in ten years time everyone will want to secure their emails most of the time. Remember, unencrypted email is more like sending a postcard than a letter! Privacy is not the same thing as secrecy – we all have the right to avoid snoopers!

Interesting links

Unpublished

Post Election blues, and it isn’t even my election…

Categories: General
Comments: No Comments
Published on: November 9, 2004

John McEnroe once said Show me a good loser, and I’ll show you a loser. I guess this quote sums up John Kerry’s snatching defeat from the jaws of victory last week.

I had fooled myself into feeling that the morning after the election I would wake into a world that had changed somehow – I was fully aware that this realisation would fade as quickly as the elation we all felt when Blair defeated the Tories in 1997 (how we laughed as Michael Portillo lost his seat.) But I did expect the elation. But it wasn’t to be. Bush came through, and you have to wonder what this means for the world? Will Iran be next on the hit list? After Iran, what next? China? Russia? For a good deal of Bush’s more religious supporters, World War III would fulfill their desire for the apocalypse. The evangelists with megaphones in London sound particularly chirpy now – more people do seem to believe we are in the end days.

What it does mean for America is that more people in the world will hate Americans. Trust for Americans is seriously eroding – if their government is so happy to walk away from treaties, why trust their business contracts? The perception of America has taken a real battering, and sooner or later this is going to disappoint Americans. Of course, they will blame other people for this, rather than seeing responsibility within America’s policies, domestic and foreign. But you can’t fix these things by launching more wars, or by pretending it is the fault of others. The biggest hurdle is, plenty of Americans don’t want to fix these things.

The irony is, a vote for Bush this time around was a vote for Hillary Clinton in four years time. Maybe we will get our shallow and short lived elation then. It would have been nice to see Bush lose though…

Security and Privacy Through Cryptography

Categories: Articles
Comments: No Comments
Published on: November 6, 2004

In the 1840s a scandal broke out in the UK shaking the postal service and government to the ground. It became apparent that agents of the government were reading the letters of political rivals before delivering them to their intended recipients. At the time letters tended to be only a single sheet of paper, folded and sealed. It was possible to squeeze the letter partially open and read the contents without alerting the recipient. After this scandal, the British public began to use a new invention to protect their messages – the humble envelope.

In the year 2000 many postal services around the world are under threat because it is now cheaper and faster to send emails than letters. We may have moved in technological terms, but in many ways we have returned to pre-envelope days where our intimate thoughts are easily intercepted and read by strangers. Like posted letters, emails pass through many hands before arriving in the recipients inbox. Like the folded notes of yesteryear, it is a simple matter to peer inside and read the contents.

What we need are electronic envelopes

It is not possible to wrap the letters and numbers that make up an email in a physical envelope. It is possible to change the letters and numbers into something that does not resemble words.

In war time, orders, tactic and other pieces of sensitive information need to be sent to distant people – generals at the front line; spies behind enemy lines. This information must not fall into enemy hands. Militaries around the world have long used secret codes to make this information useless should it be intercepted by the enemy.

This involves sharing the secret of how to decode encrypted messages with people who will be receiving future messages. However, there is a danger one of these people is captured and reveals the secret decoding methods?

It is often useful to think of encryption as involving keys and lockable boxes. A message inside a locked box can only be read if one has the key. Teaching spies and generals how to decode messages is in effect giving them the key.
But keys can be stolen and the box opened by the enemy.

In the 1960s a UK government cryptography expert, James Ellis, turned this concept on its head. Instead of delivering keys to agents in the field, running the risk of enemies capturing and copying the keys, send them an open but lockable
box. The agent could put a message in the box, and close it. If the enemy captured the box they would not be able to open it, even if they captured the spy – he would not have the key to open the box. The key would remain safely in the
hands of the recipient of the message. This is the birth of Public Key Cryptography.

Of course, there is no real box – instead there are mathematical methods for turning a message into what appears to be nonsense. The Public Key makes this transformation possible. This key cannot be used to decode a message once it is encrypted. It is therefore safe to make it public. Anyone who has this key can use it to encrypt messages, but only those with the corresponding Private Key can decode it. This key is never shared.

Which brings us back to email. It is not secure from prying eyes! Since emails pass through many computer systems on their way to their recipients there are many opportunities to open email that may contain sensitive material. Governments regularly monitor email passing through its countries borders – whether to capture terrorists and enemy agents, or crack down on political rivals, or keep an eye on its citizens. It has even been suggested that some governments pass the secrets of foreign companies to companies based in their own country.

Criminals too can gain sensitive information such as credit card numbers from emails they open.

It is also remarkably simple to send an email in someone else’s name. It is not uncommon in the USA and Europe for criminals to create emails that appear to come from a bank to trick people into giving their bank details. This information can be used to empty the accounts and run up debt in someone else’s name!

Public Key Cryptography is useful here as a Private Key can be used to sign a document – mark it with a code that can be checked against a public key. A bank would make a public key available to customers who would then be able to check if a message really came from the bank. This signature cannot be forged. The signature also confirms the integrity of the message – the message cannot be changed while on its way to the recipient without using the private key to sign the message again.

Public Key Cryptography forms the basis for a solid electronic envelope for our emails, ensuring that messages cannot be forged or altered, and also providing a means for keeping them secret.

In the next article in this series I will show you how to put Public Key Cryptography to use yourself.

Interesting links

Originally published in Arusha Times 345

page 1 of 1
Archives
Categories
Photos