[SYMBOL] [A] [B] [C] [D] [E] [F] [G] [H] [I] [J] [K] [L] [M] [N] [O] [P] [R] [S] [T] [U] [V] [W] [X] [Z] octets ethernet addresses Offset header field (TCP) Open Shortest Path First (OSPF) protocol Options header field (TCP) organizational top-level DNS domains 2nd OSPF (Open Shortest Path First) protocol |