The invention relates to a device and to a method for the packet-based access of classical ISDN / PSTN subscribers to a switching
system. The convergence of packet-based networks and TDM networks leads to a situation where classical analogous and ISDN subscribers and private
branch exchanges have to be accessed via packet-based transmission methods. Especially for the case of a failure of, for example, the subscriber terminals TNE or switching
system-related devices or intervening communication paths, it must be made sure that substitute connections can be made and stable connections can be maintained. This problem is solved by the present invention by providing a
peripheral adaptation device, integrated into the periphery of the switching
system, and being suitable for the
adaptation of the messages used on the interface between subscriber terminal and
peripheral adaptation device, to the requirements of the plurality of
peripheral devices associated with the TNE port. Furthermore,
software functions are provided for treating the failure of, for example, the subscriber terminal, the one peripheral adaptation device or one of the associated peripheral devices of the switching system. The interaction of said failure treatment
software functions controls the substitute connection and restart of failed peripheral devices, peripheral adaptation devices and communication paths to subscriber terminals.