Category: Articles

Articles I have written and that have been published somewhere – mostly the weekly Arusha Times, where I was InfoTech correspondent between 2003 and 2005.

Chatting round the world for free

dunxdLeave a comment

The first thing most people want to use the internet for is email. Never has it been so cheap, quick and easy to communicate with other people anywhere in the world. Using email, however, requires knowing your way around a keyboard, a little understanding of email addresses and how email software or webmail works. Some learning is needed before one can get started. Email is not communication in real time – you send your message and have to wait for your friend to reply. Unless they are online, chances are you won’t receive anything back until next time you visit an internet café. In these days of mobile phones this really doesn’t seem as satisfying as what we perhaps yearn for.

Then came instant messaging. Using programmes such as Yahoo! Messenger and MSN Messenger you can see when your friends are online and send and receive short messages – effectively having a conversation. This still requires knowing the keyboard. For most people who aren’t accomplished typists, replying to a message requires searching for each letter, slowing down the flow of the chat.

The most natural form of human communication is speech. Available to both young and old, it is the fastest way we can share what is on our minds. No wonder the market for mobile phones is so huge worldwide. Technology based around speaking requires the least learning. I bet your grandmother knows how to chat on the simu.

When we speak on the telephone the sound waves made by our voices are converted into electronic signals. These are transported via the phone network to the person you are calling. The internet is designed for transferring data between
computers – data is transferred as electronic signals – so why not use the internet to send our voices? It is less efficient to transfer sounds than text – after all, you can make more sounds than the 26 letters of the alphabet. Text and other simple data are cheaper to transfer over the internet than voice.

Using the internet to make phone calls is not particularly new. The technology known as Voice Over Internet Protocol (or VOIP) has been around for nearly ten years, but not widely used by anyone other than large businesses who could
afford high speed connections.

Things have moved on a long way since then. A number of internet cafes in Arusha have been offering cheap international phone calls using VOIP for at least two years. However quality was often very low while the price often was not.

As broadband connections have become more common the possibility of people using VOIP has grown. Instant messaging programmes have started to include “voice chat” capabilities – rather than typing your message why not chat
like on the phone? Yahoo! Messenger has the best voice chat of any of the instant messaging programmes. Whilst writing this article I have been chatting on Yahoo! with my friend Riz who lives in Japan. The quality is not brilliant – I can only understand about every other word that Riz says. When I don’t understand something he can type it, so the conversation is just about manageable.

I wish he would get a programme called Skype.

Skype is currently the best VOIP software available. It is free to download, and allows free calls between users of Skype, and cheap phone calls to the regular phone network in many countries. The sound quality is actually better than the telephone – when you chat using Skype it really does sound like the person is in the next room. If you want to get into voice chat, or really add some value to your internet café, Skype is a worthwhile download.

What Yahoo! has that Skype does not is the ability to use Webcams. Using a small camera connected to my computer pictures are sent along with the conversation. I can see Riz sitting at his computer. Human communication is enhanced when we can see the other person’s face – their expressions add to what they say. Whilst I can’t understand every word that Riz says I can tell if he is smiling or pausing for thought.

When Riz installs Skype we may be able to use it together with Yahoo’s webcam mode. With this technology, despite being separated by thousands of miles we can chat as if we were sitting in the pub – maybe we can enjoy a beer together on different continents.

Interesting Sites

Originally published in Arusha Times 355

Advertisement

Media Democracy through Citizen Journalism

dunxd1 Comment

When the Tsunami hit hundreds of locations in South East Asia on December 26 last year there were few journalists in place to record the disaster. However, within hours the world was shocked by photographs and video footage of the
terrible tides sweeping up beaches and laying waste to towns and villages across much of the Indian Ocean.

Many of these images were filmed by holiday makers using still and video cameras –    bought for recording happier events in their lives. Some even used cameras built into mobile phones to record the horrific scenes.

Once rescued, the first thing many survivors did was email relatives abroad to let them know they were alive. Some attached what they had seen to those emails. Others posted their experiences on blogs. Before long the amateur footage
was amongst the most startling – these were real eye witness accounts by people who came close to losing their lives and those of their loved ones.

It is possible that such images helped with the raising of funds for disaster relief from individuals who may otherwise have felt less connected to something that occurred thousands of miles away.

Although not a new phenomenon, the impact of amateurs acting as journalists is starkly revealed by coverage of the tsunami. Technology trends are putting into the hands and pockets of ordinary people tools that enable them to become
reporters, where previously only professionals could operate.

With the material they have collected, ordinary people can get published using various online services, such as personal blogs, community websites, discussion forums, or even by emailing the traditional media directly.

For many Tanzanians getting involved in this so called “citizen journalism” may seem out of the question. Whilst relatively cheap to those in wealthier countries, digital cameras and mobile phones with them built in are beyond the reach of many. However with internet cafes so common across Arusha, and strong competition keeping prices low, inventive citizens will find it possible to take part in this new publishing revolution.

If you can get hold of photographs, you can scan them. If you have something to say you can type it. At present video is out of the question, but this shouldn’t stop the budding web journalist.

It is not necessary to have your own blog to take part in this new trend. There are numerous “community blogs” out there which you can join for free and then post articles and comments on. Sites such as MetaFilter allow anyone to add new content on any subject they please. More complex sites such as Kuro5hin require material added by users is checked by other users, and an appearance on the front page is voted on by the community of people who use the site.

Contributing to one of these sites gives you a chance to be read by hundreds or thousands of other people. This is a great way to practice your writing skills as well as make new friends around the world.

Citizen journalism is not limited to individuals participating in text and image based material. One of the newest trends on the internet is “podcasting” named after the popular portable digital audio player – the iPod. Podcasting is the
web version of radio broadcasting. Podcasters record their radio style shows as MP3 files and make them available for download – listeners can save them on their hard drives and listen to them when they want. Those making regular shows can publicise them on a number of web sites, and there is software which can be used to download new shows as soon as they become available.

With most Arushans paying for their internet use by the hour putting together an article for inclusion on a web site (and certainly recording a podcast) will require writing material (or scripts) in advance to reduce time spent editing in the internet café. However it is possible to do, and is a fine opportunity for ordinary people in Tanzania to be read (or heard.)

Interesting sites

Originally published in Arusha Times 353

Surf better with a new browser

dunxdLeave a comment

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

dunxdLeave a comment

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

Security and Privacy Through Cryptography

dunxdLeave a comment

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