Dr. Takeshi Shimizu, a high-speed network expert at Media Links, presented his paper on “Non-blocking Multicast Networks for Transporting Stream Media”, proposing a new approach for building three-stage Clos networks with non-blocking multicast capability at the SMPTE 2018 conference..

A Clos network is a kind of multistage circuit switching network which represents a theoretical idealization of practical multistage switching designs. It was invented by Edson Erwin in 1938 and first formalized by Charles Clos in 1952.

Dr. Shimizu’s reviewed the massive 800 X 800 HD-SDI IP video router constructed by Media Links in 2008 by using Leaf-Spine IP architecture.

Dr. Shimizu's paper defines a brand new approach for building three-stage Clos networks with non-blocking multicast capability.

This will involve a wide-sense non-blocking (WSNB) condition and a re-arrangeable non-blocking (RNB) implementation of multicast networks.

Most importantly, this approach also enables the derivation of RNB multicast networks by reducing the number of middle switches of a given WSNB multicast network.

This can result in a reduction of up to 50% of the switches compared with the best-known WSNB designs in a relatively smaller but practical size of network.

Dr. Shimizu’s presentation will illustrate how this new theory can enable these networks to be built efficiently with up to 6 times more port counts of the building block switches.

Dr. Shimizu received the M.E. and D.E. degrees in Information Engineering from the University of Tokyo, has been with Media Links since 2015, and is a member of SMPTE, IEEE-CS, IEEE-ComSoc, the Information Processing Society of Japan (IPSJ) , and the Institute of Electronics, Information and Communication Engineers (IEICE) in Japan.