IPX's RIP is not compatible with RIP implementations used in other networking environments. As with other network addresses, Novell IPX network addresses must be unique. The IPX network number, which is assigned by the network administrator, is 32 bits long. IPX's use of a MAC address for the node number enables the system to send nodes to predict what MAC address to use on a data link. Novell NetWare IPX supports multiple encapsulation schemes on a single router interface, provided that multiple network numbers are assigned.
Encapsulation is the process of packaging upper-layer protocol information and data into a frame.
The IPX header immediately follows the 802.3 Length field. Figure 31-3 illustrates these encapsulation types. Four IPX encapsulation types exist. Advertisements are sent via SAP every 60 seconds. A SAP operation begins when routers listen to SAPs and build a table of all known services along with their network address.