That sounds similar to something to what we used to do in cross country/track training. We'd run ladders, which were:
15 sec sprints/15 sec jog
30 sec sprints/30 sec jog
45 sec sprints/45 sec jog
60 sec sprints/60 sec jog
45 sec sprints/45 sec jog
30 sec sprints/30 sec jog
15 sec sprints/15 sec jog
We'd then walk for awhile and repeat. I have no clue how many times we repeated that but it was always too many!
Of course, there'd be a warm up/cool down in there too.