Application Guide

[183]
Software User's
Manual
–
Version 3.0
Port VLAN
Determines the ports VLAN ID (a.k.a. PVID). Allowed VLANs are in the range 1
through 4095. The default being 1.
On ingress, frames get classified to the Port VLAN if the port is configured as
VLAN unaware, the frame is untagged, or VLAN awareness is enabled on the
port, but the frame is priority tagged (VLAN ID = 0).
On egress, frames classified to the Port VLAN do not get tagged if Egress
Tagging configuration is set to untag Port VLAN.
The Port VLAN is called an “Access VLAN” for ports in Access mode and
Native VLAN for ports in Trunk or Hybrid mode.
Port Type
Ports in hybrid mode allow for changing the port type, that is, whether a frame
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 egress, if frames must be tagged, they will be tagged with an S-tag.
On ingress, frames with a VLAN tag with TPID = 0x88A8 get classified to the
VLAN ID embedded in the tag.
Priority-tagged frames are classified to the Port VLAN.
If the port is configured to accept Tagged Only frames (see Ingress Acceptance
below), frames without this TPID are dropped.
Note: If the S-port is configured to accept Tagged and Untagged frames (see
Ingress Acceptance below), frames with a C-tag are treated like frames with an
S-tag.
If the S-port is configured to accept Untagged Only frames, S-tagged frames
will be discarded (except for priority S-tagged frames). C-tagged frames are
initially considered untagged and will therefore not be discarded. Later on in the
ingress classification process, they will get classified to the VLAN embedded in
the tag instead of the port VLAN ID.
S-Custom-Port:
On egress, if frames must be tagged, they will be tagged with the custom S-tag.
On ingress, frames with a VLAN tag with a TPID equal to the Ethertype
configured for Custom-S ports get classified to the VLAN ID embedded in the
tag.
Priority-tagged frames are classified to the Port VLAN.
If the port is configured to accept Tagged Only frames (see Ingress Acceptance
below), frames without this TPID are dropped.