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SG71070M
Revision A3
Port Type
Ports in hybrid mode allow for changing the port type, that is, whether a frame's VLAN tag is used to
classify the frame on ingress to a particular VLAN, and if so, which TPID it reacts on. Likewise, on
egress, the Port Type determines the TPID of the tag, if a tag is required.
Unaware:
On ingress, all frames, whether carrying a VLAN tag or not, get classified to the Port VLAN, and
possible tags are not removed on egress.
C-Port:
On ingress, frames with a VLAN tag with TPID = 0x8100 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 a C-tag.
S-Port:
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.
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.
If ingress filtering is enabled (checkbox is checked), frames classified to a VLAN that the port is not a
member of get discarded.
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.
VLAN Trunking
Trunk and Hybrid ports allow for enabling VLAN trunking.
When VLAN trunking is enabled, frames classified to unknown VLANS are accepted on the port
whether ingress filtering is enabled or not.
This is useful in scenarios where a cloud of intermediary switches must bridge VLANS that haven't
been created. By configuring the ports that connect the cloud of switches as trunking ports, they can
seamlessly carry those VLANS from one end to the other.
Ingress Acceptance
Hybrid ports allow for changing the type of frames that are accepted on ingress.
Tagged and Untagged:
Both tagged and untagged frames are accepted.
Tagged Only:
Only tagged frames are accepted on ingress. Untagged frames are discarded.
Untagged Only:
Only untagged frames are accepted on ingress. Tagged frames are discarded.
Egress Tagging
Ports in Trunk and Hybrid mode may control the tagging of frames on egress.
Untag Port VLAN
Frames classified to the Port VLAN are transmitted untagged. Other frames are transmitted with the