D-Link DES-3624 - Switch - Stackable User manual - page 69
Stackable NWay Ethernet Switch User’s Guide
packet. If Ingress filtering is disabled and the destination
port is a member of the VLAN used by the ingress port, the
packet will be forwarded. If the ingress port is an untagging
port, it will only check the filter condition--if the filter
condition is enabled-- before forwarding the packet.
♦ Egress port A port on a switch where packets are flowing
out of the switch, either to another switch or to an end
station, and tagging decisions must be made. If an egress
port is connected to an 802.1Q-compliant switch, tagging
should be enabled so the other switch can take VLAN data
into account when making forwarding decisions. If an egress
connection is to a non-compliant switch or end-station, tags
should be stripped so the (now normal Ethernet) packet can
be read by the receiving device.
VLANs Over 802.1Q-compliant Switches
When switches maintaining the same VLANs are 802.1Q-
compliant, it is possible to use tagging. Tagging puts 802.1Q
VLAN information into each packet header, enabling other
802.1Q-compliant switches that receive the packet to know
how to treat it. Upon receiving a tagged packet, an 802.1Q-
compliant switch can use the information in the packet header
to maintain the integrity of VLANs, carry out priority
forwarding, etc.
Data transmissions between 802.1Q-compliant switches take
place as shown below.
Switch Management Concepts
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