Router's Responsibility - 3Com LANPLEX 2500 EXTENDEDPLEX®2500 EXTENDED User Manual

To find this router, the sending node broadcasts a RIP packet requesting the
best route to the destination node's network number. The router residing on
the sending node's segment with the shortest path to the destination
segment responds to the RIP request. The router's response includes its
network and node address in the IPX header. If the sending node is a router
rather than a workstation, the router can get this information from its
internal routing tables and need not send a RIP request.
Once the sending node knows the router's node address, it can send
packets to the destination node.

Router's Responsibility

When a router receives an IPX packet, it handles the packet in one of two
ways:
If the packet is destined for a network number to which the router is
directly connected, the router performs the following tasks:
Places the destination node address from the IPX header in the
destination address field of the MAC header.
Places its own node address in the source address field of the MAC
header.
Increments the Transport Control field of the IPX header and transmits
the packet on the destination node segment.
If the packet is destined for a network number to which the router is not
directly connected, the router sends the packet to the next router along the
path to the destination node as follows:
The router looks up the node address (in the routing information table)
of the next router and places the address in the destination address field
of the packet's MAC header. For more information on routing tables, see
the next section.
The router places its own node address in the source address field of the
packet's MAC header.
The router increments the Transport Control field in the IPX header and
sends the packet to the next router.
How IPX Routing Works 6-7