The aim of this book is: To learn about different basic components that are used in telephone exchanges - Difference between an automatic exchange and manual exchange - To learn about different types of electronic exchanges and about the software architecture used in an electronic exchange - To differentiate between a single stage and a multistage network - To understand the advantages of multistage network over a single stage network - Design of multistage network to reduce blocking of calls - Design of multistage network to reduce the number of switching matrices - To teach different types switching techniques that are used in exchanges such as time division, time switching, time division space switching and combination of both types of switching.