Radia Joy Perlman (born 1951) is a software designer and network engineer. She is most famous for her invention of the spanning-tree protocol (STP), which is fundamental to the operation of network bridges, while working for Digital Equipment Corporation. She also made large contributions to many other areas of network design and standardization, such as link-state protocols, including TRILL, which she invented to correct some of the shortcomings of spanning-trees.She is currently employed by EMC Corporation.