Refer to Figure 21-1 on page 543. The LRH:LNH (Link Next Header) field defines the packet type as one of the following:
00b = Raw EtherType packet. The LRH is immediately followed by the RWH (Raw) header.
01b = Raw IPv6 packet. The LRH is immediately followed by the IPv6 Routing Header.
10b = IBA local packet. The LRH is immediately followed by the BTH field.
11b = IBA global packet. The LRH is immediately followed by the GRH field.