Abstract: In an ATM network in which an SPVC is realized and in which in order to carry out speedily the detection of failures on a line, a software PVC realized by a P-NNI, i.e., a PVC is established between a source private network and a destination private network, and the dynamic routing is carried out between ATM switching equipment on the basis of the establishment of an SVC, the ATM switching equipment is provided with failure detecting means for detecting occurrence of failures on a line in an ATM physical layer. A failure information reporting cell containing therein the information which is used to specify at least the source ATM switching equipment and the failure destination ATM switching equipment is produced on the basis of the failures which have been detected in the physical layer and the occurrence of the failures is reported to each of the ATM switching equipment.

Abstract: Speech over an analog telephone set or an internet phone device in a LAN telephone networ k is actualized by connecting internet phone devices or analog telephone sets to a LAN telephone switching apparatus. Herein, it is permitted to form a system of telephone numbers which differ from LAN addresses being unique in the LAN telephone network, so that the network telephone set can be used with the same feel as that of a conventional extension telephone. Besides, address setting for the individual analog telephone sets or internet phone devices is automatically performed. Moreover, local IP addresses being unique in the LAN telephone switching apparatus are used as IP addresses which are set for the individual sets or devices, so that the problem of the exhaustion of the number of IP addresses can be solved.