摘要 |
<p>An internet based telephone apparatus for embodying a telephone-to-telephone type of internet based telephone, the apparatus having a gateway function where a communication is possible between a general telephone connected via PSTN with another internet based telephone connected through internet network without separate internet telephone gateway installed between the internet network and PSTN, and a dual channel communication function where a communication is possible by being connected to a third internet based telephone when there is a communication connection between a general telephone connected via PSTN and a second internet based telephone connected through internet network.</p> |