Multistage Distribution Switching Systems: Clos and Beyond

Marc S. Walker

The average size of distribution switchers in television facilities is growing larger each year. In 1953, Charles Clos published a landmark technical paper concerning nonblocking multistage switching techniques, explaining how to reduce the number of crosspoints when compared to a standard switcher. Since that time, multistage switching systems have been proposed and used by several companies in the television industry. This article discusses the basic principles of multistage switching and the problem of blocking in television systems. It explains the causes of blockage, shows statistical results demonstrating the amount that may occur, and discusses ways to deal with these issues.

Print ISSN
Published
1991-12
Content type
Original Research
DOI
10.5594/J02378