Common cryptographic key establishment method for subscribers involves successively combining two known secret values into a new common value throughout using Diffie-Hellmann technique

摘要

The method involves using the Diffie-Hellmann or DH technique. A leaf of a binary structured tree with exactly n leaves and depth log2n is allocated to each of the n subscribers (A,B,C). A secret value is generated for each subscriber, and is associated with the relevant leaf. Secret values are established successively towards the tree root for all nodes of the tree, in which two known values are always combined into a new common value. This is done throughout using the DH technique, and is associated with a common node so that the last node (KW), and hence the root, contains the common key for all subscribers.