The value of tmnxIPMafMatchProtNxtHdr specifies
for IPv4 MAF the IP protocol field, and for IPv6 the next header
type to be used in the match criteria for this Management Access
Filter Entry.
Some well-know protocol numbers are TCP (6), and UDP (7).
The value of -1 is used to indicate that this object is not
initialized.
The value of -2 is used to indicate udp/tcp protocol matching