1) sequence numbering
2) protocol control information such as FECN,BECN
3) packet padding (to reach min. MPLS packet size)
padding small packets
carrying control bits of the Layer2 header of the transported protocol
preserving the sequence of the transported frames
facilitating the correct load balancing of AToM packets in the MPLS backbone
facilitating fragmentation and reassembly
Was it a multiple-choice type of question or you had to spell out all 5 functions?
I had to spell out three out of five fuctions.