| 摘要 |
<p>PURPOSE:To select a relay line without causing a call interruption of a packet terminal equipment by providing a relay line communication control section having an exchange function between the X25 protocol and the frame relay protocol to the system. CONSTITUTION:X25C105, 122 are provided to the system, which implements speech control between PKT116, 129 in its own station and TRKC102, 119 having an exchange function between the X25 protocol and the frame relay protocol and has a re-transmission function of a layer 3 between other station and a communication control section. Then the frame relay protocol is adopted and the re-transmission control of the X25 protocol is implemented between the X25C105, 122 to prevent call interruption between the PKT116, 129.</p> |
