Scenarios Showing Vlan Translation; Carrier Ethernet Configuration Guide (Cisco Asr 920 Series - Cisco ASR 920 Series Configuration Manual Ethernet Router

Scenarios showing VLAN Translation

achieved. In a scenario with two EFPs egressing the same interface, each EFP can have a different VLAN
rewrite operation, which is more flexible.
VLAN translation feature includes the following functionalities:
• 1:1 VLAN translation - The VLAN of the incoming traffic (CE VLAN) is replaced by another VLAN
• 2:1 VLAN translation - The double tagged (Q-in-Q) traffic at the U-PE UNI port can be mapped to
• 1:2 VLAN translation - The outermost tag can be replaced with two tags. The CoS field of the new tags
• 2:2 VLAN translation - The outermost two tags can be replaced with other two tags. The CoS field of
Scenarios showing VLAN Translation
The following scenarios show the VLAN translation.
Scenario 1 - 1:1 VLAN Translation
Figure 5: 1:1 VLAN Translation
In the scenario above, t he broadcast or multicast from CPE1 has to be sent to CPE2 and CPE3. The incoming
tag in the frame has a CoS value of 3. The service needs to be created that enables the CoS value to pass
transparently to the other sites with the desired VLAN translation.
This behavior can be achieved using the 1:1 VLAN translation command on the service instance attached to
CPE1. The Egress Service instance on Remote UPE device should be configured with the right encapsulation
or Rewrite operation to achieve the correct tagging behavior (VLAN 50 on outgoing tag) for CPE3. As there
is no inner tag here, the outer CoS is propagated in the newly added tag to both CPE2 and CPE3 ACs.

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(PE VLAN). The specification of the VLAN translation happens during the creation of the service
request. The CoS field of the new tag is set to the same value as the CoS field of the existing VLAN
tag.
different flows to achieve service multiplexing. The CoS field of the new tag is set to the inner CE-VLAN
(second tag) CoS value.
is set to the same value as the CoS field of the incoming 802.1Q VLAN tag.
the new tags is set to the same value as the CoS field of the incoming Q-in-Q (outer and inner tag CoS)
service frame.
VLAN Translation with QoS