EXP Computer S200 manual Using Filters

Transparent Bridging for Ethernet LANs

Using Filters
Support
	The Forwarder provides its own filtering facility which is used to reduce unnecessary
	traffic and to provide security. The filtering facility supports the following types of
	filters:
	• Incoming Source Address Filter
	• Incoming Destination Address Filter
	• Outgoing Source Address Filter
	• Outgoing Destination Address Filter
Incoming Source
	The Incoming Source Address Filter filters packets are based on their source address
Address Filter	and incoming links. Frames with a source address found in the Incoming Source
	Address Filter List are discarded without applying bridge logic. This filter may be
	applied to all links or selected links.
Incoming
	The Incoming Destination Address Filter filters packets based on their destination
Destination	address and the incoming ports. Frames with a destination address found in the
Address Filter	Incoming Destination Address Filter List are discarded without applying bridge
	logic. This filter may be applied to all links or selected links.
Outgoing Source
	The Outgoing Source Address Filter filters packets based on their source address and
Address Filter	the outgoing links. Frames with a source address found in the Outgoing
	Source Address Filter List are discarded. This filter may be applied to all links or
	selected links.
Outgoing
	The Outgoing Destination Address Filter filters packets based on their destination
Destination	address and the outgoing links. Frames with a destination address found in the
Address Filter	Outgoing Destination Address Filter List are discarded. This filter may be applied to
	all links or selected links.
Unicast Link
	When a frame comes from a link with the Unicast Link Protect Flag set, and if its
Protect Flag	source address is not found in the Permanent Station Address list, the frame is
	dropped.

When a frame is being sent out over a link with the Unicast Link Protect Flag set, and if its destination address is not found in the Permanent Station Address List, the frame is dropped.

Once the Unicast Link Protect Flag is set for a link, source address learning for Unicast frames is stopped for that link and all the addresses that were learned before are moved into the Permanent Station Address List.

Setting or Clearing of Unicast Link Protect Flag is performed via the LAN Control menu located in the Main menu.

54 Bridging