In order to reinforce the competitivity in the domestic telecommunication industry, Specific services institutionalized in the beginning of 1998, are divided into 3 parts, specific $1^st$, $2^nd$,$3^rd$. Specific service providers providing the various services have entered the market more easily than common carriers by the benefit of lower sunk cost, cream skimming behavior. However, in order to use the specific service, Customers have pushed much more digit than that of PSTN service while using resale service and have submitted lower quality of service than that of PSTN service while using Internetphone.
This thesis for the analysis on the effects of the common carriers by specific service provider's entering the telecommunication market, is divided into 3 parts largely.
First, analysis on the competitive structure between common carriers and specific service providers.
Second, Making the profitability model of common carriers influenced by specific service providers.
Third, Making the model of the profitability test resulted from the profitability model of common carriers and strategic countermeasure to the each of the specific service providers.
