Router Interfaces; Router's Responsibility; Elements Of Ipx Routing - 3Com CoreBuilder 2500 User Manual

Elements of
IPX Routing

Router Interfaces

Router's Responsibility

A router handles a received IPX packet in one of two ways:
If the packet is destined for a network number to which the router is
directly connected, the sending router:
Places the destination node address from the IPX header in the
destination address field of the packet's MAC header
Places its own node address in the source address field of the
packet's 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. The sending 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 about routing
tables, see "Elements of IPX Routing," next.
Places its own node address in the source address field of the
packet's MAC header
Increments the transport control field in the IPX header and sends
the packet to the next router
IPX routers use the following elements to transmit packets over an
intranetwork:
Router interfaces
Routing tables
Service Advertising Protocol (SAP)
A router interface connects the router and the network number (address).
In traditional routing models, the router interface is the same as the port,
because only one interface exists per port. But in the CoreBuilder 2500
system, more than one port can connect to a network number. Therefore,
the router interface is a relationship between one or more ports and the
network number (address) in your IPX network.

Elements of IPX Routing

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