
Lantronix
SM24TBT2DPA and SM24TBT2DPB Web User Guide
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 relevant tag.
Tag All:
All frames, whether classified to the Port VLAN or not, are transmitted with a tag.
Untag All:
All frames, whether classified to the Port VLAN or not, are transmitted without a tag.
This option is only available for ports in Hybrid mode.
Allowed VLANs
: Ports in Trunk and Hybrid mode may control which VLANs they are allowed to become
members of. Access ports can only be member of one VLAN, the Access VLAN.
The field's syntax is identical to the syntax used in the Existing VLANs field. By default, a port may
become member of all possible VLANs, and is therefore set to 1-4095.
The field may be left empty, which means that the port will not be member of any of the existing VLANs,
but if it is configured for VLAN Trunking it will still be able to carry all unknown VLANs.
Forbidden VLANs
: A port may be configured to never be member of one or more VLANs. This is
particularly useful when dynamic VLAN protocols like MVRP and GVRP must be prevented from
dynamically adding ports to VLANs.
The trick is to mark such VLANs as forbidden on the port in question. The syntax is identical to the syntax
used in the Allowed Access VLANs field.
By default, the field is left blank, which means that the port may become a member of all possible VLANs.
Buttons:
Apply
– Click to save changes.
Reset -
Click to undo any changes made locally and revert to previously saved values.