Algorithm 4 CCRA

1:   ${\psi }_f$: the set of failed nodes which need to be restored

2:   if node $i\in {\psi }_f$ has no failed neighbor(s) in the same grid then

3:    if node $i\in {\psi }_f$ has no failed neighbor(s) in the neighbor grid then

4:     recovery process goes to case 2)

5:    else

6:     restore the connectivity similar to CSFR-M

7:    end if

8:   else

9:    if the connected failed nodes are all inner-grid nodes then

10:     recovery process goes to case 1)

11:   else

12:     if the connected failed nodes are all inter-grid nodes then

13:      recovery process goes to case 4)

14:     else

15:      recovery process goes to case 3)

16:     end if

17:    end if

18: end if