Qinq (Double Tagging) For Service Providers; Vlan Untagging; Port Functionality; Figure 14-2 S - Radwin WinLink 1000 User Manual

QinQ (Double Tagging) for Service Providers

IEEE 802.1Q is used as the encapsulation protocol to implement this mechanism over Ether-
net networks.
QinQ (Double Tagging) for Service Providers
QinQ is useful for Service Providers, allowing them to use VLANs internally in their "transport
network" while mixing Ethernet traffic from clients that are already VLAN-tagged.
Figure 14-2: Separating client data streams using double tagging
The outer tag (representing the Provider VLAN) comes first, followed by the inner tag. In
QinQ the EtherType = 0x9100. VLAN tags may be stacked three or more deep.
When using this type of "Provider Tagging" you should keep the following in mind:
• Under Provider Tagging, the system double-tags egress frames towards the Provider's
network. The system adds a tag with a VLAN ID and EtherType = 0x9100 to all
frames, as configured by the service provider (Provider VLAN ID).
• The system always adds to each frame, tags with VLAN ID and EtherType = 0x9100.
Therefore,
• For a frame without a tag – the system will add a tag with VLAN ID and
EtherType = 0x9100 so the frame will have one tag
• For a frame with a VLAN tag – the system will add a tag with VLAN ID and
EtherType = 0x9100 so the frame will be double-tagged
• For a frame with a VLAN tag and a provider tag – the system will add a tag with
VLAN ID and EtherType = 0x9100 so the frame will be triple-tagged and so on

VLAN Untagging

VLAN Untagging means the removal of a VLAN or a Provider tag.

Port Functionality

The VLAN functionality is supported by all LAN and SFP ports in the IDU.
Each port can be configured how to handle Ethernet frames at the ingress direction (where
frames enter the IDU) and at the egress direction (where frame exit the IDU).
The configuration is independent at each port.
WinLink 1000 User Manual Release 1.9.40
Chapter 14
14-2