By Cho Jin-seo
Staff Reporter
A series of Internet attacks on the Web sites of computer game item trading companies left them paralyzed until Friday.
The attacks by the unidentified hackers have put a stop to the operation of three major trading sites since Monday. It was the first such attack on the online traders, which has grown into a 1-trillion won industry _ though they have been criticized by some computer gamers and NGOs that they are causing the games to deteriorate.
The firms said that the culprits sent enormous amounts of data requests to computer servers, making them unable to respond to the increased traffic and eventually shutting them down. This trick is called a denial-of-service (DoS) attack.
``We will take strong actions against these illegal activities in cooperation with the Korea Information Security Agency,'' said the association of three firms _ Item Bay, Item Playforum and Item T. ``Private data of customers is secure as DoS attacks do not infiltrate the system,'' they added.
Item trading has become a lucrative business in South Korea as the popularity of addictive online games has given virtual items commercial value.
It is estimated that there are about 200 item trading Web sites, which take about 5 percent of the sales price as commission. Item Bay, the largest of them, earned 17.1 billion won in commission and 5.4 billion won in net profit.
Perpetrators of DoS attacks typically target well-known sites or services. But while this week's attacks were focused on the item trading companies, they didn't hurt the online game service companies themselves. Firms said that the hackers targeted the trading firms because their security systems are relatively vulnerable compared with those of game operators.
``They know that they cannot easily damage us. `Look before you leap' is what they are doing,'' said an official of NCsoft, the largest online game company in South Korea, which runs popular games such as ``Lineage'' and ``Guild Wars.''
The most advanced and trickiest form of a DoS attack is the Distributed Denial of Service Attack (DDoS), which occurs when hundreds of thousands of computers are manipulated by computer virus programs to attack a targeted system all at once.
Meanwhile, a similar DoS attack hit The Korea Times Web site between Wednesday and Thursday. The newspaper has found that the attack was initiated from a foreign Internet address. Operation returned to normal Thursday afternoon.