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Each group of devices is assigned a unique “network number” which repre- sents that particular group to all of the routers on the network. Packets which are sent between members of the same group are simply sent directly from one member to another.
Packets which must go between devices belonging to two different groups travel through routers, which forward them along an optimal path.
By examining the destination network number in a packet that must be forwarded, and by using information that routers automatically pass between themselves in IPX Routing Information Protocol (RIP) packets, any router can determine the optimal path for forwarding packets from one group to another.
This scheme relies on the fact that each segment is assigned a unique network number. If not, the routers have no way of knowing which of the physical segments with that number should actually receive a packet.
Backbone
Net:100
Workstation
Local Net
Net:10C01
Router
Workstation
IPX Routing Example
Among routable network protocols, IPX is relatively simple. Each physical network segment is assigned a network number by the routers on the segment. The network number can be in the range of 1 to FFFFFFFE (that’s 8 hexadec- imal digits). In the diagram above, 100 and 10C01 are the network numbers for the two segments shown.
Establishing the network number for an IPX network segment is referred to as “seeding” the network. You should generally only have one seed router per