Alloy AS5010-P, User Manual

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AS Series User Manual
195
Doc No.: AS5-0116-01
following characteristics:
• By default, a trunk port is member of all existing VLANs. This may be limited
by the use of Allowed VLANs.
• unless VLAN Trunking is enabled on the port, frames classified to a VLAN
that the port is not a member of will be discarded.
• By default, all frames except frames classified to the Port VLAN (a.k.a. Native
VLAN) get tagged on egress. Frames classified to the Port VLAN do not get C-
tagged on egress.
• egress tagging can be changed to tag all frames, in which case only tagged
frames are accepted on ingress.
• VLAN trunking may be enabled.
Hybrid:
Hybrid ports resembles trunk ports in many ways, but adds additional port
configuration features. In addition to the characteristics described for trunk
ports, hybrid ports have these abilities:
• Can be configured to be VLAN tag unaware, C-tag aware, S-tag aware, or S-
custom-tag aware.
• ingress filtering can be controlled.
• ingress acceptance of frames and configuration of egress tagging can be
configured independently.
Port VLAN
Determines the port's VLAN ID (a.k.a. PVID). Allowed VLANs are in the range 1
through 4095, 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
Only ports in hybrid mode allow this value to be modified.
A frame's VLAN tag is used to classify the frame on ingress to a particular VLAN,
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.