From a New York Telephone advertisement in 1987:
Intellipath II Digital Centrex Service is the latest step in the continuing evolution of Centrex. It’s the first fully digital telecommunications system that requires no major switching equipment on your premises: it’s in New York Telephone’s central office.
Intellipath II offers 100 features: full-featured voice, full data transmission at up to 56 kbps with data call protection and a Centrex LAN option. So you can have all the features of advanced on-premises systems without the headaches.
Like all Centrex telecommunications systems, Intellipath II frees you from the worries of maintenance and obsolescence. New York Telephone monitors your system at its central office around the clock. And we continually incorporate new technologies into our network as they are developed, and offer them to you — to keep your system at the leading edge.
Best of all, you won’t have to make a major capital investment. With Intellipath II you pay for service as you use it. You get a customized system at a competitive price. [in Network World, July 20, 1987, p. 33]
That’s the promise of cloud services more than two decades ago. Telephone companies have grown mainly on the basis of selling connectivity (lines and minutes), not services to connected customers. Changing from selling connectivity to selling services to connected customers is a difficult business change.