ppp0                                                                     00:10 
  ^                                                                    r        
  |                                                                    r        
  |                                                                    r        
  |                 r                                                  r        
  |                 r                                                  r        
  |                 r                                                  r        
  |                 r                                                  r        
  |                 r                                               r  r  r     
  |                 rt                                              r  rt r     
  |              r  rt                                              rt rt rt    
 -+---------------------------------------------------------------------------> 
  |  18 19 20 21 22 23 00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16 17    
                                                                                
 h   rx (kB)    tx (kB)      h   rx (kB)    tx (kB)      h   rx (kB)    tx (kB) 
18          0          0    02          0          0    10          0          0
19          0          0    03          0          0    11          0          0
20          0          0    04          0          0    12          0          0
21          0          0    05          0          0    13          0          0
22         33         18    06          0          0    14          0          0
23        156         49    07          0          0    15         70         26
00          1          1    08          0          0    16        203         59
01          0          0    09          0          0    17         75         24