Em 1985, a Engenheira de Redes e Designer de Software Radia Perlman criou um algoritmo que foi base para o surgimento do Spanning Tree Protocol, regulamentado em 1990 como IEEE 802.1d. Para explicar o funcionamento deste algoritmo Radia criou o poema abaixo:
Algorhyme (by Radia Perlman)
I think that I shall never see a graph more lovely than a tree.
A tree whose crucial property is loop-free connectivity.
A tree that must be sure to span so packets can reach every LAN.
First, the root must be selected.
By ID, it is elected.
Least-cost paths from root are traced.
In the tree, these paths are placed.
A mesh is made by folks like me,
then
Fonte: CONSULTOR TéCNICO LEGISLATIVO - INFORMáTICA / Câmara de São Paulo/SP / 2014 / FCC