Intuitive ISDN - An ISDN Tutorial

‘‘Intuitive ISDN’’—An ISDN Tutorial AN-492National Semiconductor‘‘Intuitive ISDN’’— Application Note 492Doug GremelAn ISDN TutorialBob PoniatowskiDecember 1991WHAT IS ISDN? THE CASE FOR ISDNThe Integrated Services Digital Network, commonly called Without a doubt the past decade has brought us a one hun-ISDN, is simply an all digital communications network which dred fold increase in the utilization of data processing. Un-offers its users a variety of different capabilities. In due time, fortunately, that increase has come at the cost of not beingthe ISDN will change the way that many, if not all of us able to effectively communicate and share our individualcommunicate, be it through voice, data or video communi- data. We have created isolated islands of data processing.cation. To that end, the ISDN is an invisible rebuilding of the For years now, telephone exchanges throughout the worldexisting telephone network that will allow simultaneous have taken advantage of the capabilities of digital centralvoice and data communication over ordinary telephone office switching. This is due in great part to help from prod-lines. TMucts such as National’s COMBO family, which does theWhat are the advantages that an integrated services digital analog to digital conversion of voice signals. If one’s voicenetwork will offer? In order for ISDN to be successful, cus- conversation can be converted to a series of 1’s and 0’s ittomers must see an economic payoff associated ...