Algorithm 3: Cluster Maintenance

1: if ACK from $C{M}_j$ is not heard by$CH$ 2:  deplete $C{M}_j$ from CM list 3: end if 4: if $C{H}_i$ leaves the cluster 5:  execute Algorithm 2 6: end if 7: if a new node requests to join the cluster 8:  the new node sends HELLO message to $C{H}_i$ 9:  if (remaining energy of the new node $>$ $E_{th}$) 10:   $C{H}_i$reply ACK and agree to join 11:  else 12:   ignore the request 13:  end if 14: end if