By Kim Tae-gyu Koreans will soon be able to place a call to an Internet-enabled telephone through a mobile phone and vice versa as Korean firms continue to make technical breakthroughs. Anyusernet, a local Internet telephony service provider, said on April 3 that a subscriber of SK Telecom, the nation's top wireless operator, successfully made a call to an Internet phone with the dialing prefix of 070. The company already confirmed the interconnection with smallest mobile carrier LG Telecom on April 1 and plans to carry out the final tests with the only remaining mobile player, KTF. Internet telephony, or called voice over Internet protocol (VoIP), is an emerging technology that connects voice calls via the Internet instead of conventional telecom lines. Accordingly, costs go down dramatically and end-users can enjoy international calls at very low prices with some operators even offering free service. However, three hitches have dampened the promising service's full-fledged takeoff: people could not receive calls through the phone, the mobile phone was excluded from the VoIP concept, and service quality is only about 75 percent of conventional phones. Korea has addressed two of the three problems. The government introduced two-way Internet phoning last year by giving eleven-digit VoIP-specific numbers with the dialing prefix of 070 and four outfits, including Anyusernet, have received a license. In addition to Anyusernet, VoIP licensee Samsung Networks also plans to connect its Net phone network with that of mobile operators. "We aim to sign an agreement with fixed-line entity KT to provide Internet telephony services for both wireline and wireless soon," an Anyusernet official said. Experts predict that the technical wizardry of establishing pipelines between Internet phones and mobile phones will help the new business to take firm root in a short period. "The new technical development is likely to substantially improve the commercial viability of the interactive VoIP business, combined with the envisioned participation of bigger players," Dongwon Securities telecom analyst Greg Roh said. The government has thus far allocated the two-way VoIP licensees to small-sized firms to prevent bigger players from overwhelming the market. Yet large-scale telecom firms, which have their own networks, will be allowed to jump onto the two-way VoIP bandwagon starting in the latter part of this year and KT and Hanaro Telecom have already applied for licenses. The Ministry of Information and Communication, which overseas the VoIP business, is optimistic about the future of Internet phones and has predicted that they will go mainstream by 2010. Domestic researcher IDC Korea also estimates the size of Korea's VoIP market would expand about 8-fold during the next five years from 109 billion won this year to 808 billion won in 2008.