Foreword

Vint Cerf

Internet Pioneer, Woodhurst, February 2014

It is no exaggeration to say that the Internet has become an integral part of the lives of nearly three billion people on the planet. More important, it touches nearly everyone thanks to the ramifications of transactions, information exchange, and other Internet-based applications that produce indirect effects. The original Internet Protocol provided for a maximum of 4.3 billion terminal identifiers (addresses). This limit was stretched using a mechanism called Network Address Translation that permitted multiple parties to use private address space that would not be exposed in the public Internet but rather translated into a shared, publicly routable IPv4 address. The IPv4 address space was exhausted at the Internet Corporation for Assigned Names and Numbers (ICANN) in February 2011, leaving Regional Internet Registries to deal with the allocation of their remaining address space. IPv6 was developed in the mid-1990s and standardized by the Internet Engineering Task Force (IETF). It has provision for 340 trillion trillion trillion addresses. Its implementation has been slow, but two milestones are triggering an increased rate of uptake. One is the running out of the IPv4 address space. The other is the growing demand for Internet addresses to be assigned to mobiles, set-top boxes, automobiles, and literally tens of billions of other programmable devices. This is the so-called Internet of Things.

In addition to satisfying what will become an insatiable demand for address space, IPv6 has features that improve the Internet Protocol format for easier processing and provides for additional functionality in the way of configuration convenience and flow management, among other useful properties. Readers will find this book an easily approached guide to IPv6 implementation. That IPv6 must coexist for an uncertain period of time with IPv4 is a given, so attention is drawn to so-called dual-stack implementations. A thorough implementation of IPv6, however, must also demonstrate that the implementation can operate in a pure IPv6 environment in addition to coping with a mixed IPv4/IPv6 environment.

Like many exponential phenomena, IPv6 may well come to surprise us. It has been many years since its development, but there is indication that it is approaching 3% of traffic on the Internet. While this seems very small, it will grow rapidly if history is any guide, presuming continued compounding growth of need for the larger address space.

Anyone serious about making a career in Internet-related applications and services will be wise to become familiar with this new protocol and its functionality and capability. You have this opportunity before you in Silvia Hagen’s work.

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