Notation for tree Sample Clauses

Notation for tree. Each group member contributes an equal share to the group key. The key is computed as a function of all current group members’ shares. – Each share is secret (private to each group member) and is never revealed. – As the group grows, new members’ shares are factored into the group key and, upon each new member’s joining, one of the old members changes its share. – As the group shrinks, departing members’ shares are removed from the new group key, and at least one remaining member changes its key share4. – All protocol messages are signed, timestamped, sequence-numbered and type-identified by the sender; as dis- cussed at the end of Section 3. (We use RSA for message signing since the number of receivers is greater than the number of senders. )