Progress on the development and introduction of isdn in the linea ut

The technical solutionsfor theprogressive introduction ofthe ISDM ca pabilifies in die LINEA UT switching system are pre sented. Thepresent implementation conforms to the requirements of the Italian Initial ISDN Service, promoted by SIP; this first JS,DN release constitutes an important milestone for the further developments required by the large scale ISDN deployment of the subsequent commercial diffusion. The LINEA UT evolution through the commercialup to the matureISDNphaseis envisaged preserving the already installed exchanges.