Patent ID: 8582777

Claim:
A lightweight key distribution method for a backbone node of a wireless network, the method comprising: receiving a connection request message from a new node intending to join the wireless network; sending an identification (ID) to allocate to the new node and a certificate to verify the ID to the new node as a response to the receiving of the connection request message; receiving a key request message from the new node, the key request message including the allocated ID and the certificate; generating a session key as a result of the receiving of the key request message; calculating a second intermediate value by applying a first concatenated value to a hash function, the first concatenated value being acquired by concatenating the session key and a first intermediate value that corresponds to respective partial keys included in a key pool; generating an encryption key using the calculated second intermediate value, the generating of the encryption key comprising: extracting a common key index from a key index of the backbone node; and applying a second concatenated value to a hash function, the applying of the second concatenated value comprising acquiring the second concatenated value, the acquiring of the second concatenated value comprising concatenating the calculated second intermediate value corresponding to the extracted common key index; encrypting a partial key corresponding to the common key index with the generated encryption key, the common key index including commonalities existing between the key index of the backbone node and a key index of the new node; and sending a key part that includes the encrypted partial key and the second intermediate value to the new node.