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).
An implication of defining telecommunications broadly is that every layer involved in communication at a distance becomes, at least partially, part of the telecommunications industry. The broad range and large number of companies that contribute to the telecommunications industry are evident in the following list of examples:
Networking service providers across the Internet and the PSTN, wireless carriers, and cable operators. Examples include AT&T, Comcast, Verizon, and DirecTV.
Communications equipment suppliers that are the primary suppliers to service providers. Examples include Cisco, Lucent, and Motorola.
Networking equipment suppliers selling products to end-user organizations and individuals. Examples include Cisco’s Linksys division and Hewlett-Packard (local area networking products).
Semiconductor manufacturers, especially those supplying system-on-a-chip solutions for the telecommunications industry. Examples include Texas Instruments, Qualcomm, Broadcom, and STMicroelectronics.
Suppliers of operating systems that include a networking stack. Microsoft is an example.
Software suppliers, especially those selling infrastructure and applications incorporating or based on real-time media. Examples include IBM, RealNetworks (streaming media), and BEA (application servers).
Utility or on-demand service providers selling real-time communications-oriented applications. Examples include AOL and Microsoft (instant messaging) and WebEx (online meetings).
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