74
Any frame (untagged, single tagged, dual tagged or multiple tagged) arriving at a
Tunnel
port will be added
the assigned VLAN ID and be sent to the opposite end over the modem port.
If the opposite end has a fully identical VLAN setup, the traffic will egress at the same port as the original
port without the added tag (same frame as the original frame with any customer VID). Internal VIDs inside
the hop are invisible to the outer world and no co-ordination with the customer VID is required.
Figure 65. Transparent tunnelling over a microwave hop. The tunnels are fully transparent to any frames and are
invisible to each other.
If it is desired to keep the assigned outer tag at the other end and aggregate traffic to a single port, then
the port type is set to trunk and assigning all VIDs to the same port. Figure 66 below.
Figure 66. Traffic aggregation. Customer tunnels terminated in a single
Trunk
port
Again, in this case the customer VIDs may be unknown, but the outer tags need to be coordinated on the
core network side and processed somewhere else in the network.
