I travel with my mobile device, and get email with GPRS, the 2.5G mobile phone service. It is cheap and not very fast, but quite suitable for text-based messages. The device also has wi-fi function for Internet browsing, so I can check wi-fi hotspots wherever I go. Wi-fi is quite common nowadays. We use it at home and most telecommunication services now provide extensive wi-fi coverage in Hong Kong at a fee.
When I travelled to Israel last month, I obtained free wi-fi service both at the Hong Kong Airport as well as the Tel Aviv Airport. Many hotels I stayed also offered wi-fi service at a small fee on a hourly or daily basis. Wi-fi is both a business and a public service on citizens’ right to information. It is not a surprise to read the following announcement that the Hong Kong Government is going to offer free wi-fi service at government buildings and public places.
(明報) 03月 07日 政府免費無線上網料快可實行
With more and more free wi-fi hotspots at convenient locations, there is tremendous pressure on the business of the internet service providers and other telecommunication service providers. I envisage that free Internet service will become more common with the service providers turning to advertisement revenue instead of subscription fees from clients.
However, free wi-fi service means more data transmitting freely on radio frequency. This poses serious threat to data security: a good subject for managers of information technology. I read from CNet an article on “Your Wi-Fi can tell people a lot about you“. If you are interested, please take a look.
Almost all new personal computers in various form factors are now equipped with wi-fi function. The article reveals the fact that as soon as such computers power up, they start looking for wireless networks and network services. Shortly after start-up, computers typically broadcast the previous Internet Protocol address and details on networked drives or devices such as printers that it tries to connect to. Even if the wireless hardware is then shut-off, someone may already have caught interesting data. Much more information can be plucked out of the air if the computer is connected to an access point, in particular an access point without security. For a computer using Windows, it will emit upon startup the list of wireless networks the PC has connected to in the past. The list can be used to determine where a laptop computer has been used.
There are many tools that let anyone listen in on wireless network traffic. These tools can capture information such as username and password for e-mail accounts and instant message tools as well as data entered into unsecured Web sites. At the annual Defcon hacker gathering, a speaker demonstrated the technique to exploit the loophole by capturing log-in credentials of the participants from radio signals of wi-fi network at the venue.
These are bits of friendly information, but in the hands of the wrong person, they could help attack the computer owner or network. Furthermore, the information could be useful to intelligence organizations. If the computer is then connected to a wireless network, particularly the unsecured type at hotels, airports and coffee shops, much more can be gleaned. The advice of the expert is: The best solution is to be aware of the danger, and everyone doesn’t need to work from a coffee shop. When I used the free wi-fi service at the airports, I only browsed for news. Online banking and other personal services are done at home.