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In the new public network, we are moving from a narrowband to a broadband world, meaning we are going from single-channel to multichannel arrangements, and we are also moving from low bandwidth to high bandwidth. We're also shifting from a circuit-switched environment to a packet-switched environment. Circuit switching implies the use of an exclusive channel—one channel, one conversation for the duration of that call—whereas packet switching allows multiple conversations to share one channel. (Circuit switching and packet switching are discussed in detail in Chapter 4, "Establishing Communications Channels.")

We're also quickly departing from an era in which we try to force data to run over a network that was largely built for voice. We're moving toward a network where we're applying voice to data applications so that they can run over the higher-quality digital networks. We're shifting from electronic networks to all-optical networking. This transition will take some time, perhaps three to five years.

Another shift is from single media to multimedia (that is, multiple media types and personal control over what you view, when you view it, and in what combination). The shift continues, from just voice to multimodal combinations (that is, combinations in which you have further control in selecting exactly what appeals to your cognitive map). For example, some people would rather see the movie than read the book, and others prefer the book, so not everybody responds to things the same way. People think in different ways, and we need to provide all the modalities that enable individual choice over the various media formats.

We're also shifting from a fixed environment to a mobile environment, and that will have a dramatic impact on the types of applications we want served over wireless networks. (See Chapter 14.) This shift goes a step further: from portable computers to wearable computers, from unresponsive stand-alone devices to affective, wearable friends.

Because of all these forces, convergence is occurring in many different areas.

Convergence occurs in networks, where the PSTN, the Internet, wireless alternatives, broadcast networks, and cable TV, as well as the back-office functions that support them, are all coming together to service the same sets of traffic and to deliver the same types of features and services. Network services are converging because customers prefer bundled services. They want one bill, one provider for local, long distance, wireless, Internet access, hosting, applications partnering, security features, firewall protection, conversions from legacy systems, and settlement processes.

Convergence also occurs in devices, such as televisions, telephones, computers, smart appliances, intelligent clothing and jewelry, and smart tattoos. (See Chapter 15.)

Convergence occurs in applications as well. Communications, information services, entertainment, e-commerce and m-commerce, and affective computing are all overlapping and blending with one another to create new generations of traditional applications such as edutainment and infotainment. Going forward, we're relying on the bright young minds that have been born into a digital economy to fantasize about brilliant new applications that are beyond the traditional forms.

Convergence happens in industries. Today industries share digital technology as a common denominator, so biotechnology, computing, consumer electronics, entertainment, publishing, power utilities, and telecommunications are all coming together and finding reasons and synergies for why they should work together or become one.

Finally, convergence occurs in humans and machines. Today we have artificial limbs and organs, and we have intelligent implants. Tomorrow, we may see neural interfaces and artificial life.

As you can see, telecommunications is much more than just a set of technologies or business plans, and it's more than an industry in which you can guarantee success and early retirement. It's a way of life—and the more you understand that, the more fun you'll have learning the technical details.

For more learning resources, quizzes, and discussion forums on concepts related to this chapter, see http://www.telecomessentials.com/learningcenter.

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