METHOD AND SYSTEM FOR DISTRIBUTING CRYPTOGRAPHIC KEYS IN A HIERARCHISED NETWORK

摘要

The invention relates to a method for distributing cryptographic keys in a hierarchised network that comprises at least one device in charge of a higher group of devices, at least one of the devices of said group of devices also being in charge of a lower group of devices, wherein said method comprises the steps of: a) storing (20, 22) a set of identifiers particular to the higher group, of an identifier particular to the device in charge, of an identifier per device in charge of a lower group, each identifier being unique inside the hierarchised network; storing (24) a root cryptographic key; c) providing (26, 28) a root cryptographic key to each device in charge of a lower group by derivation of the root key and of the identifier of said device in charge of a lower group using a first non-reversible cryptographic function; d) providing (30, 32) at least one transport cryptographic key to each member of said higher group of devices by derivation of the root key and of an identifier belonging to the set of identifiers particular to said group using a second non-reversible cryptographic function.