Security Assumptions and Attack Models Sample Clauses

Security Assumptions and Attack Models. The security assumptions and attack models is discussed as follows. 2.6.3.1 There is no single member controlling the execution of the protocol but there is some “leader” it is short-lived and restricted to that particular execution of the protocol. 2.6.3.2 The contributory group key management requires each group member to contribute an equal share to the common group key (which is then computed as a function of all members’ contributions). This avoids the problems with the centralized trust and the single point of failure. Source Destination Member node Non-member node 2.6.3.3 If the group memberships are not changed, protocol have to refresh the key periodically, There are two main reasons, one is to limit exposure due to loss of group session keys, the other is to limit the amount of ciphertext available to cryptanalysis for a given group session key. This makes it important for the key refresh protocol not to violate key independence. Additionally, note that the loss of a member’s key share can result in the disclosure of all the session keys to which the member has contributed with this share. 2.6.3.4 The solution did not distinguish between an attacker and a compromised node, because the protocol assume that an attacker can obtain all the information stored in a compromised node. Since wireless communication is broadcast-base, assumed that an adversary can eavesdrop on all traffic, inject packets, and replay older packets. Since it is assumed that an adversary can take full control of compromised nodes, an adversary may command compromised nodes to drop off alter messages they are forwarding.