The buffer receives {HEAD ~ a data frame} to be transmitted to {TAIL ~ a destination device} via the switching fabric 
to be transmitted to
The buffer receives { HEAD ~ a data frame } to be transmitted to { TAIL ~ a destination device } via the switching fabric
OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH