Chapter 7. Voice over Cellular and Licensed Spectrum
7.0. Introduction
Voice mobility is centered around the concept that the call should follow the user. What happens when the Wi-Fi network runs to the end of its coverage, and yet people still want to place a call? When the callers are out in the city, or driving to their next meeting, they need to retain their access to the voice services. The only way to get the phone to work is if it hooks up to a licensed mobile operator who provides coverage around the wider areas beyond the building or the campus.
Cellular networking remains the predominant method that people get voice mobility today. Adding in-building, privately managed wireless extensions such as Wi-Fi for voice to operate on is still ...

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