PART 1 Circuit-Switched Services „h POTS (Plain Old Telephone Service) -- not a computer data service, but included for two reasons: (1) many of its technologies are part of the growing data infrastructure, (2) it is a model of an incredibly reliable, easy-to-use, wide-area communications network; typical medium is twisted-pair copper wire „h Narrowband ISDN (Integrated Services Digital Network) -- a versatile, widespread, historically important technology; was the first all-digital dial-up service; usage varies greatly from country to …showed first 75 words of 1196 total…

…showed last 75 words of 1196 total…-- primary paths for traffic that is most often sourced from, and destined for, other networks „h autonomous system (AS) boundary routers -- communicate with routers in other autonomous systems While no one entity controls them, the typical entities are: „h corporations (e.g. MCI Worldcom, Sprint, AT&T, Qwest, UUNet, France Telecom) „h universities (e.g. University of Illinois, Stanford University) „h research institutes (e.g. CERN in Switzerland) „h Internet Service Providers (ISPs)