Perhaps the most fundamental change, both in terms of technology and its implications for industry structure, has occurred in the architecture of telecommunications networks. Architecture in this context refers to the functional description of the general structure of the system as a whole and how the different parts of the system relate to each other. Previously the PSTN, cable, and data networks coexisted as separately owned and operated networks carrying different types of communications, although they often shared a common technology base (such as point-to-point digital communications) and some facilities (e.g., high-speed digital pipes shared by different networks).
No longer a vertically integrated business, the telecommunications industry is enabled by a complex value chain that includes vendors, service providers, and users. The telecommunications value chain begins with building blocks such as semiconductor chips and software. These components are, in turn, incorporated into equipment and facilities that are purchased by service providers and users. The service providers then, in turn, build networks in order to sell telecommunications services to end users. The end users include individuals subscribing to services like telephony (landline and cellular) and broadband Internet access, companies and organizations that contract for internal communications networks, and companies and organizations that operate their own networks. Some major end-user organizations also bypass service providers and buy, provision, and operate their own equipment and software, like a corporate local area network (LAN) or a U.S. military battlefield information system. Software suppliers participate at multiple points in the value chain, selling directly not only to equipment vendors but also to service providers (e.g., operational support systems) and to end users (e.g., various PC-based applications for communications using the Internet).
We'll begin our mission with the originator- the telephone. Since it's invention, the device has gotten smaller, portable, and even wireless. Accessories such as answering machines can attach to your phone or phone line for friends, family and/or clients and customers to leave you an important message when you're unavailable to take a call. All-in-one answering machine/telephone contraptions have gained substantial popularity in recent years as the price dropped with the advancement of technology. Multi-line telephones for busy offices are also becoming more affordable for those who didn't have the extra funding for such a telecommunications device.
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