User’s Manual of IGS-20040MT
On ingress, frames with a VLAN tag with TPID = 0x8100 or 0x88A8 get
classified to the VLAN ID embedded in the tag. If a frame is untagged or
priority tagged, the frame gets classified to the Port VLAN. If frames must
be tagged on egress, they will be tagged with an S-tag.
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S-Custom-Port:
On ingress, frames with a VLAN tag with a TPID = 0x8100 or equal to the
Ethertype configured for Custom-S ports get classified to the VLAN ID
embedded in the tag. If a frame is untagged or priority tagged, the frame
gets classified to the Port VLAN. If frames must be tagged on egress, they
will be tagged with the custom S-tag.
Ingress Filtering
Hybrid ports allow for changing ingress filtering. Access and Trunk ports always
have ingress filtering enabled.
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If ingress filtering is enabled (checkbox is checked), frames classified to a
VLAN that the port is not a member of get discarded.
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If ingress filtering is disabled, frames classified to a VLAN that the port is
not a member of are accepted and forwarded to the switch engine.
However, the port will never transmit frames classified to VLANs that it is not a
member of.
Ingress Acceptance
Hybrid ports allow for changing the type of frames that are accepted on ingress.
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Tagged and Untagged
Both tagged and untagged frames are accepted.
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Tagged Only
Only tagged frames are accepted on ingress. Untagged frames are
discarded.
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Untagged Only
Only untagged frames are accepted on ingress. Tagged frames are
discarded.
Egress Tagging
This option is only available for ports in Hybrid mode. Ports in Trunk and Hybrid
mode may control the tagging of frames on egress.
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Untag Port VLAN
Frames classified to the Port VLAN are transmitted untagged. Other
frames are transmitted with the relevant tag.
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Tag All
All frames, whether classified to the Port VLAN or not, are transmitted
with a tag.
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Untag All
All frames, whether classified to the Port VLAN or not, are transmitted
without a tag.
Allowed VLANs
Ports in Trunk and Hybrid mode may control which VLANs they are allowed to
become members of. The field's syntax is identical to the syntax used in the
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