Qinq Configuration; Figure 4-24 Typical Qinq Networking - Zte ZXR10 2910E-PS Configuration Manual

4.21 QinQ Configuration

QinQ Overview
QinQ is the IEEE 802.1Q tunneling protocol and is also called VLAN stacking. QinQ
technology is the addition of one more VLAN tag (outer tag) to the original VLAN tag (inner
tag). The outer tag can shield the inner tag.
QinQ does not need the protocol support. The simple Layer 2 Virtual Private Network
(L2VPN) can be realized through QinQ. The QinQ is especially suitable for the small-size
LAN that takes the layer-3 switch as its backbone.
Figure 4-24
the user network is called Customer port. The port connected to the ISP network is called
Uplink port. The edge access equipment of the ISP network is called Provider Edge (PE).

Figure 4-24 TYPICAL QINQ NETWORKING

The user network is generally connected to the PE through the Trunk VLAN mode. The
internal Uplink ports of the ISP network are symmetrically connected through the Trunk
VLAN mode.
1. When a packet is sent form user network 1 to the customer port of switch A, because
the PORTBASE VLAN-based customer port does not identify the tag when receiving
the packet, the customer port processes the packet as an untagged packet no matter
whether this data packet is attached with the VLAN tag or not. The packet is forwarded
by the VLAN 10, which is determined by the PVID.
2. The uplink port of switch A inserts the outer tag (VLAN ID: 10) when forwarding the
data packet received from the customer port. The tpid of this tag can be configured
on the switch. Inside the ISP network, the packet is broadcast along the port of VLAN
10 until it reaches the switch B.
3. Switch B finds out that the port connected to user network 2 is a customer port. Thus, it
removes the outer tag in compliance with the conventional 802.1Q protocol to recover
the original packet and sends the packet to user network 2.
4. In this way, data between user network 1 and user network 2 can be transmitted
transparently. The VLAN ID of the user network can be planned regardless of the
conflict with the VLAN ID in the ISP network.
Configuring QinQ
The QinQ configuration includes the following commands:
SJ-20120409144109-002|2012-07-02(R1.0)
shows the typical networking of the QinQ technology. The port connected to
Chapter 4 Service Configuration
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