5.1 INTRODUCTION

This chapter deals with the architecture used in allocating IPv6 unicast addresses in the Internet. The Internet can be conceptualized as a collection of hosts interconnected through transmission and switching facilities. The control over the aggregate of hosts, transmission, and switching facilities is what constitutes the networking resources of the Internet. This is not a homogeneous mix, but it is distributed throughout several administrative powers.

Domains that share their resources with other domains are referred to as network service providers. Domains that use other domain's resources are designated as network service subscribers. A domain may perform as a provider and as a subscriber at the same time.

In IPv6 unicast address allocation within the Internet there are two distinct aspects:

In the Internet, there exists several routing domains (the subscribers) including corporate and campus networks that are attached to transit networks in only a small number of precisely controlled access points (the provider).

There are several benefits of encoding some topological data in IPv6 addresses to extensively decrease routing protocol overhead. The preferred mapping is between Internet service providers/service subscribers and IPv6 addressing and routing components. The best segmentation of IPv6 address assignment is through service providers such as backbones, regionals, and service subscriber sites. In addition, the allocation of the IPv6 addresses (illustrated...