User guide

Chapter 1. Router Concepts 17
How Routing and Bridging Work Together
The router follows these rules when operating as both a router and a bridge:
¥ The router operates as a router for network protocols that are enabled for routing (IP or IPX).
¥ The router operates as a bridge for protocols that are not supported for routing.
¥ Routing takes precedence over bridging; i.e., when routing is active, the router uses the packetÕs protocol
address information to route the packet.
¥ If the protocol is not supported, the router will use the MAC address information to forward the packet.
Routing and Bridging Controls
The router can be configured to perform general routing and bridging while allowing you to set specific controls.
¥ One remote router can be designated as the outbound default bridging destination. All outbound bridging
traffic with an unknown destination is sent to the default bridging destination.
¥ Bridging from specific remote routers can be controlled by enabling or disabling bridging from individual
remote routers.
IP/IPX Routing On Bridging to/from Remote Router Off
Data packets carried IP (TCP, UDP), IPX
Operational
characteristics
Basic IP, IPX connectivity
Typical usage When only IP/IPX trafÞc is to be routed and all other trafÞc is to be
ignored. For IP, used for Internet access.
Note: This is the most easily controlled configuration.
IP/IPX Routing On Bridging to/from Remote Router On
Data packets carried IP/IPX routed; all other packets bridged.
Operational
characteristics
IP/IPX routing and allows other protocols, such as NetBEUI (that canÕt
be routed), to be bridged.
Typical usage When only IP/IPX trafÞc is to be routed but some non-routed protocol is
required. Used for client/server conÞgurations.
IP/IPX Routing Off Bridging to/from Remote Router On
Data packets carried All packets bridged.
Operational
characteristics
Allows protocols, such as NetBEUI (that canÕt be routed) to be bridged.
Typical usage Peer-to-peer bridging and when the remote end supports only bridging.