ABSTRACT
Previously in this book we discussed several variations of ADSL (Assymetrical Digital Subscriber Line), including ADSL2 and ADSL2
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. We noted their use in the literal “last mile” to provide communications connectivity from a home or office to fiber located in the neighborhood or on a direct run to a telephone company central office that was in close proximity to the customer. Although we covered the use of different versions of ADSL in detail earlier in this book, in this chapter we will examine the use of the technology in conjunction with several methods of installing fiber cable to central locations where groups of homes and offices are clustered. In addition, we will discuss a version of digital subscriber lines referred to as VDSL (very-high-bit-rate DSL) that can provide very high bandwidth for relatively short distances and may offer an alternative or supplement to the use of various versions of ASDL. Because understanding VDSL will provide a foundation for discussing alternative last mile solutions, we will commence our examination by focusing on that topic.
