Very good presentation by Dr. Radia Perlman. The talk discusses spannig tree protocol and new work being done in IETF known as TRILL (TRansparent Interconnection of Lots of Links), which combines the advantages of bridges (layer 2 forwarding devices) and routers (layer 3 forwarding devices).

Dr. Radia Joy Perlman is a software designer and network engineer sometimes referred to as the 'Mother of the Internet'. She is most famous for her invention of the spanning-tree protocol, while working for Digital Equipment Corporation, which is fundamental to the operation of network bridges. She also made large contributions to many other areas of network design and standardization such as link-state protocols.

Perlman is the author of two textbooks on networking. She is currently employed by Sun Microsystems.