Algorithm 1: Reputation Management and Leader Election Algorithm

Require:

blockHash(previous): Hash of previous block

block#(response): Block number of response time

block#(request): Block number of request time

Repi: Reputation of each oracle node

procedure Reputation_Management():

1: sum ← 0, i ← 1

2: RTleader = (block#(response) − block#(request)) × blockInterval

3: while i ≤ Noracle do

4:  sum += RTi

5:  i ≤ i + 1

end

6: AvrgRT = sum/Noracle

7: Rleader = AvrgRT/RTleader

8: Cleader = min(Nresponse/Nlimit, 1)

9: Repleader = Repleader × Rleader × Cleader

10:

procedure Leader_Election():

11: sum ← 0, i ← 1

12: while i ≤ Noracle do

13:  sum += Repi

14:  i ← i + 1

end

15: mod = blockHash(previous)%sum

16: while mod ≥ 0 do

17:  mod = mod − Repi

18:  if mod < 0 then

19:   i-th oracle node is elected as a leader node

end

20:  i ← i + 1

end