Algorithm 1 PEAFC-CL

Upon Timer

BS: broadcast “$Beacon$” frame in network

foreach sensor node $N_i$ do

Reset $C_{i\_request}$ to 0

Upon receiving a beacon frame from BS

Compute $L_{i\_loss}$

send “$\mathrm{Pr}obe\_request$” frame (contain: $E_{i\_curr}$, $C_{i-request}$, $L_{i\_loss}$)

end

Upon receiving a Probe request frame from $N_i$

BS compute: $N_{active}$, $M_{i\_curr}$, $M_{r\_aver}$, $M_{r\_\max }$, $E_{r\_\max }$, $E_{r\_aver}$

If $T_{\text{initialize}}$ < current time < $T_{\text{initialize}}+T_{\text{CH-election}}$ then

BS broadcast “$START\_MSG$” (contain: $N_{active}$, $M_{i\_curr}$, $M_{r\_aver}$, $M_{r\_\max }$, $E_{r\_\max }$, $E_{r\_aver}$)

foreach sensor node $N_i$ do

$W_{i\_r}$ ← Random (0, $W_r$)

If $W_{i\_r}$ < $T_i(t)$ then

Be cluster head ← $TRUE$

$N_i\in G_{CH}$

else

Be cluster head ← $FALSE$

$N_i\in {\overline{G}}_{CM}$

end

end

else if $T_{\text{initialize}}+T_{\text{CH-election}}$ < current time < $T_{CF}$ then

foreach CH node do

Broadcast “$CLUSTER\_HEAD\_MSG$” message

Upon receivingh a “$REQ\_JOIN(\mathrm{int}ended\_ID,C{M}_j)$” message

if $CH\_ID=\mathrm{int}ended\_ID$ then

Record information contained in “$REQ\_JOIN$”

Add $C{M}_j$ to CH Member node list

else

Discard “$REQ\_JOIN$”

end

end

foreach CM node do

Upon receivingh a “$CLUSTER\_HEAD\_MSG$” message

Compute: $L_{i-C{H}_n}$, $L_{i-all}$

If $L_{i-C{H}_n}+L_{C{H}_n-BS}<L_{i-C{H}_m}+L_{C{H}_m-BS}$ and $L_{i-C{H}_n}+L_{C{H}_n-BS}<L_{i-BS}$ then

$\mathrm{int}ended\_ID\Leftarrow C{H}_n\_ID$

Broadcast “$REQ\_JOIN(\mathrm{int}ended\_ID,C{M}_j)$” message

end if

end

end