Optical Systems Design OSD2524, User Manual

Page: 189 / 402

OPTICAL SYSTEMS DESIGN
DOC ID: 10120001
OSD2524 OPERATOR MANUAL
PAGE 189
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.
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. See Port Type for a description of when a frame is
considered tagged.
Tagged Only
Only frames tagged with the corresponding Port Type tag are accepted on ingress.
Untagged Only
Only untagged frames are accepted on ingress. See Port Type for a description of when a frame is
considered untagged.
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 Enabled VLANs field. By default, a Trunk or
Hybrid port will become member of all VLANs, and is therefore set to
1-4095
.
The field may be left empty, which means that the port will not become member of any VLANs.
Forbidden VLANs
A port may be configured to never become 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 Enabled VLANs field.
By default, the field is left blank, which means that the port may become a member of all possible
VLANs.