Chapter 2 - Creating an Addressing Plan for Fixed-Length Mask Networks

This chapter focuses on creating an addressing plan for fixed-length mask networks. The chapter also provides the solution for the problems of determining the addressing requirements, reviewing internetwork design, how many subnets does one need, how many IP addresses are needed in each subnet, its growth, and choosing the proper mask by consulting the tables. There are four options to find an appropriate mask : use of unnumbered interfaces, asking for a bigger block of addresses, playing some tricks with the router, and use of "subnet zero." Next it is explained how to obtain IP Addresses from three sources in order: organization's network manager, Internet Service Provider, and the Internet Address Registry. The chapter also explains how to calculate ranges of IP addresses for each subnet, doing it the hard way as well as using subnet calculators. An overview of allocating addresses to devices is provided here. The steps required to develop an effective IP plan for networks with fixed masks are presented in the chapter.