# Perfect shuffle in parallel processing

How is Perfect shuffle a better interconnect scheme for parallel processing? For example if we consider a problem of sum reduction, I want to understand how this scheme is useful when implementing sum reduction in parallel , for example on a GPU?

The perfect shuffle alone has never been used as an interconnection network; it always included exchange links, in order to allow for a worst-case $O(\lg n)$ routing algorithm. Algorithms for reduction, broadcast, parallel prefix, transpose etc are given in