To flexibly deal with various types of media and networks and to improve reliability and maintainability in a gateway apparatus for connecting an existing public switched telephone network (PSTN) to an IP network.
The apparatus is configured so that hardware is separated into function blocks such as PSTN interface sections 10, processing section 20 for having a function of exchanging between a PCM (pulse code modulation) signal and an IP packet, and control sections 40 for controlling the overall apparatus. The hardware blocks are exchanged each other depending on the types of opposite networks or media, thereby dealing with various types of PSTNs, IP networks or various services such as VoIP (voice over IP) or NAS/ RAS. Also, the apparatus is constituted so that the duplexed control sections 40 can be accessed from a maintenance system or the like by a single MAC address, and further, the apparatus is provided with a means for autonomously performing restoration at the time of malfunction due to logical inconsistency in software, and a file breakdown prevention means.
HIKITA KOJI
YAMADA KENJI
