SWITCHING SYSTEM WITH OAM PROCESSOR CAPABLE OF AUTOMATICALLY UPDATING DIRECTORY TRANSLATION DATA BASE

In a telephone switching system, a directory translation data base is created in a read/write memory, a call handling processor makes a search through the data base for reading routing data to establish a connection in a switching network. A copy of the data base is created in a backup memory. An area code is entered through a video display terminal to an OAM processor, which responds to it by making a search through the data base in the backup memory for a corresponding tree structure linking directory translation tables on a digit-by-digit basis and comparing the number of digits in the entered area code is then compared with the number of digits in the corresponding tree structure. If the number of digits in the area code is greater than the number of digits in the corresponding tree structure, the OAM processor creates an (N+1)th table in the backup memory, rewrites an N-th table of the corresponding tree structure with a next table pointer so that the N-th and (N+1)th tables are linked, and writes routing data into the (N+1)th table. If the number of digits in the area code is smaller than the number of digits in the corresponding tree structure, the processor removes an (N+1)th table of the corresponding tree structure and rewrites an Nth table of the corresponding tree structure with routing data. When the backup memory is updated, the OAM processor copies the updated data base onto the read/write memory.