Input：segmented FS point α，task request ti，routes pi，and the topology of SEON G

Output：allocated FS block for task request ti

1 for each link in routes pi do

2 calculate the feasible FS block

3 end for

3 if no feasible FS block exist do

4 block the task request ti

5 else

6 If nfi≥α do

7 select the available FS block with the lowest starting index

8 else

9 select the available FS block with the highest starting index

10 end if

11 end if