User's Guide

88
Bridging
The SkyWay Bridge/Router can function as either a bridge or a router or both. When a
packet arrives at the bridge, SkyWay examines it and determines its protocol type. The
packet is then forwarded or discarded, depending on the functions enabled on the
bridge:
• Bridging only - All packets are forwarded without regard to protocol
• Routing only - Only IP suite packets are forwarded; all other protocols are dis-
carded
• Bridging and routing - IP suite packets are routed; all other protocols are
bridged
However, if IP packets are sent to the bridge itself (its own IP address), it will accept
them even if it is configured for bridging only.
Enabling and Disabling Bridging
Bridging is a global parameter, and the SkyWay Bridge/Router is configured by default
with bridging. Disable bridging in “1.3.1 Bridge Configuration” on page 90. In this
screen you also set the global bridge parameters when bridging is enabled. Then set
up the ports for bridging operation in “1.3.2 Bridge Port Configuration” on page 92.
If you enable bridging, the bridge receives the frame and determines what action
should be taken, that is, to forward or “filter” (drop the packet), based on the state of
the bridge ports.
Port States
Each bridge port has a state associated with it. The port state is set by management or
dynamically by other means (such as the Spanning Tree algorithm). There are five port
states:
Port State Description
Blocking The port does not forward frames,
but is included in the Spanning Tree
topology.
Listening The port is ready to forward frames,
and Learning is disabled.
Learning The port is ready to forward frames,
and Learning is enabled. The port is
still not forwarding.
Forwarding The port is forwarding frames.
Disabled The port does not forward frames,
and is not included in the Spanning
Tree topology.