| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a communication system capable of accommodating a synchronous network device through an IP line, and a gateway device and adapter device used for the system. <P>SOLUTION: The gateway device 10 extracts a network clock of a line switching network 100 and multiplexes IP packets to packet converting devices 30 and 31 in fixed-length frames synchronized with the network clock. The packet converting devices 30 and 31 regenerates PCM data and the network clock from the fixed-length frames and transmits them to a base station. Consequently, the clock can be transmitted in a layer closer to the physical layer between synchronous networks via the IP network without using techniques such as CES (Circuit Emulation System) etc. Namely, an STM node having an existent STM interface can be clock-synchronized with the network clock of the line switching network 100. <P>COPYRIGHT: (C)2008,JPO&INPIT |
