Abstract: An integrated broadband and narrowband access arrangement, includes a multiplexed ATM adapter and an ATM core. The ATM core terminates a broadband access system and a narrowband access system whereby to deliver ATM cells to a SDH/ATM trunk or to the adapter. The services comprising the narrowband system are terminated each by a respective adapter providing an individual virtual circuit connection to the multiplexed adapter. The narrowband services within that virtual circuit having permanently assigned time slots whereby to retain time slot sequence integrity throughout the adaptation process.

Abstract: A database contains listing records, and index records each providing a pointer to a listing record. The index records are stored, in a predetermined order, together with distributed free space to allow the future insertion of new index records. Each index record is provided with a radix sort key associated with a primary keyword in the corresponding listing record whereby that index record may be inserted in the correct order without reference to the listing record.