Asante Technologies 9000 manual Port Admit Frame Type, Port Ingress Filtering

Advanced Management

frame. Ports should have a non-zero VID associated with them. By default, the PVID of all ports is 1, in compliance with IEE P802.1Q specifications. The allowed PVID range is 1-4094. The PVID of 4095 is assigned to ports that are configured to receive only 802.1Q tagged frames. See the “Port Admit Frame Type” section for details.

Port Admit Frame Type

All ports are set by default to receive both 802.1Q VLAN tagged frames and untagged frames. According to IEEE P802.1Q, a port should be configurable to admit only 802.1Q VLAN tagged frames. Untagged frames are filtered unconditionally on the ports that are set to admit only 802.1Q tagged frames; the source MAC addresses of the incoming untagged frames are not learned either. When a port is set to receive only 802.1Q tagged frames, it’s PVID has no meaning, and is therefore assigned the value of 4095. Incoming tagged frames are classified to the VLAN represented by the VID in the tag header of the frame. See the “Port Ingress Filtering” section for more information about forwarding and filtering of received tagged frames.

This feature is helpful in setting up Intra Switch Link (ISL) configuration. {need more information}

Port Ingress Filtering

This feature controls the learning and filtering behavior of the ports for which there are incoming untagged and tagged frames. If a port’s ingress filtering is disabled, the learning of incoming source addresses and the forwarding of untagged and tagged frames happens in the switch regardless of whether the ingress port is a member of the incoming frame’s VLAN classification or not. But when ingress filtering is enabled, incoming untagged and tagged frames are filtered unconditionally, as long as the ingress port is not a member of the frame’s VLAN classification. There is also no learning of the source address.

This feature is helpful in setting up Intra Switch Link (ISL) configuration. {{need more information}}

VLAN Port Membership and Untagging

Port members can be added to and deleted from a VLAN Group. This operation is mainly useful in defining the configuration discussed in the {cf IVL/SVL} section. When you add a port member to a VLAN, it is added to the untagged set by default; this means the frames sent out on this port will be untagged. To change the egress frame type, the port has to be deleted from the

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