Algorithm 2. Low-power Failure Detector.

Input: $d_1$, $S{M}_1$

Output: suspectlist[]

1.  Node q: /*monitoring node*/

2.  Task 1:

3.    if $p\notin suspectlist[]$ and did not receive heartbeat within freshpoint $\tau$

4.      then add p to suspectlist[];

5.    end if

6.  Task 2:

7.    upon receiving heartbeat message $m_j$ from p;

8.      if $j>s{n}_l$

9.        if $p\in suspectlist[]$

10.         then remove p from suspectlist[];

11.           $\epsilon =\epsilon +1$;

12.         else

13.           $\epsilon =1$;

14.         end if

15.         $d_j=(T_{now}-T_{pre})/N_l$;

16.         $E{A}_{j+1}=I{D}_j\cdot {\eta }_j+d_j$;

17.         ${\widehat{d}}_{j+1}=k\ast {\widehat{d}}_j+(1-k)\ast d_j$;

18.         $S{M}_{j+1}=\epsilon \left|{\widehat{d}}_{j+1}-d_j\right|$;

19.         ${\tau }_{j+1}=E{A}_{j+1}+S{M}_{j+1}$;

20.     end if

21. Node p: /*detected node*/

22.  for all $i>1$ do

23.    at time ${\eta }_i$: (the i-th detection period);

24.    send heartbeat message $m_i$ to node q;

25.    ${\eta }_{i+1}\leftarrow \mathrm{Algorithm} 1$;

26.  end for