A traffic manager generates {HEAD ~ a tree scheduling hierarchy} having {TAIL ~ a root scheduler} and N scheduler levels 
A traffic manager generates { HEAD ~ a tree scheduling hierarchy } having { TAIL ~ a root scheduler } and N scheduler levels
OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH