A Reputation-Based Approach Using Consortium Blockchain for Cyber Threat Intelligence Sharing
Algorithm1
Leader and supervisor election phase.
Data: state: the state of a node, num: total number of nodes in the CTI sharing consortium network.
Result
: void
(1)
begin
(2)
switch state do:
(3)
case “follower” do:
(4)
communicate with the current Supervisor node by ReputationValue RPC;
(5)
update the UNL data of local;
(6)
if receive the RequestVote RPC from candidate then:
(7)
if candidate is not in UNL then: Ensure that only the faithful node can serve as the leader /
(8)
vote to candidate;
(9)
else:
(10)
reject vote to candidate;
(11)
if not receive the heartbeat request from the leader in a period then: The timeout of the heartbeat request indicates that there is no leader node in the current network /
(12)
state = candidate;
(13)
break
(14)
if the term in heartbeat request from the leader is less than current term then: The leader’s term must be greater than or equal to the term of current network /
(15)
state = candidate;
(16)
break
(17)
else if the node is not in UNL then: The faithful follower node can become the supervisor node in the new term /
(18)
become supervisor and step to phase 2;
(19)
break
(20)
case “candidate” do:
(21)
for i = 1, i++, i<=num do:
(22)
communicate with the node i by using RequestVote RPC;
(23)
if received vote from most follower nodes then:
(24)
the number of term is increase;
(25)
become the leader and step to phase 2;
(26)
break
(27)
else:
(28)
state = follower;
(29)
break
(30)
case supervisor do:
(31)
If receive the ReputationValue RPC from follower node then:
(32)
send UNL data to node;
(33)
if receive the RequestVote RPC from candidate node then:
(34)
if candidate is not in UNL then:
(35)
vote to candidate;
(36)
else:
(37)
reject vote to candidate;
(38)
if the term in heartbeat request from the leader is more than current term then:
(39)
become the follower and step to phase 2; the supervisor node of last term no longer serves as supervisor in the new term /
