Chapter 56 VLAN
OLT2406 User’s Guide
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the default VID of the ingress port is given as the VID of the frame. Of the 4096 possible VIDs, a VID of 0 is
used to identify priority frames and the value 4095 (FFF) is reserved, so the maximum possible number of
VLAN configurations is 4,094.
56.3.1 Forwarding Tagged and Untagged Frames
Each port on the OLT is capable of passing tagged or untagged frames. To forward a frame from an
802.1Q VLAN-aware switch to an 802.1Q VLAN-unaware switch, the OLT first decides where to forward
the frame and then strips off the VLAN tag. To forward a frame from an 802.1Q VLAN-unaware switch to
an 802.1Q VLAN-aware switch, the OLT first decides where to forward the frame, and then inserts a
VLAN tag reflecting the ingress port's default VID. The default PVID is VLAN 1 for all ports, but this can be
changed.
A broadcast frame (or a multicast frame for a multicast group that is known by the system) is duplicated
only on ports that are members of the VID (except the ingress port itself), thus confining the broadcast to
a specific domain.
56.4 Static VLAN
Use a static VLAN to decide whether an incoming frame on a port should be
• sent to a VLAN group as normal depending on its VLAN tag.
• sent to a group whether it has a VLAN tag or not.
• blocked from a VLAN group regardless of its VLAN tag.
You can also tag all outgoing frames (that were previously untagged) from a port with the specified
VID.
56.5 VLAN Configuration Overview
1 Use the vlan <vlan-id> command to configure or create a VLAN on the OLT. The OLT automatically
enters config-vlan mode. Use the exit command when you are finished configuring the VLAN.
2 Use the interface port-channel <aid> command to set the VLAN settings on a port. The OLT
automatically enters config-interface mode. Use the pvid <vlan-id> command to set the VLAN ID
you created for the port-list in the PVID table. Use the exit command when you are finished configuring
the ports.
Note: The OLT will always configure the ONT to send out US packets with VLAN tag. The PON
port must always be configured as egress tagged.
TPID
2 Bytes
User Priority
3 Bits
CFI
1 Bit
VLAN ID
12 bits