0,Router shall examine packet,[RFC2113]
1-32,Aggregated Reservation Nesting Level,[RFC3175]
33-64,QoS NSLP Aggregation Levels 0-31,[RFC5974]
65,NSIS NATFW NSLP,[RFC5973]
66-65502,Unassigned,
65503-65534,Reserved for experimental use,[RFC5350]
65535,Reserved,[RFC5350]