2.
Selective QinQ
Selective QinQ is implemented based on interfaces and VLAN IDs. That is, an interface
can forward packets based on a single VLAN tag or double VLAN tags. In addition, the
device processes packets received on an interface as follows based on their VLAN IDs:
l
Adds different outer VLAN tags to packets carrying different inner VLAN IDs.
l
Marks outer 802.1p fields and adds different outer VLAN tags to packets according to
the 802.1p fields in inner VLAN tags.
In addition to separating carrier and customer networks, selective QinQ provides extensive
service features and allows flexible networking.
QinQ/Dot1q VLAN Tag Termination Sub-interface
Termination removes the single or double tags from packets before the packets are sent.
Different termination modes are used in different situations when QinQ technology is applied
to an MPLS/IP core network.
Termination is performed on a sub-interface; therefore, a sub-interface used for terminating
VLAN tags is called a termination sub-interface. A termination sub-interface can be either of
the following:
l
Dot1q VLAN tag termination sub-interface: removes a single VLAN tag from packets.
l
QinQ VLAN tag termination sub-interface: removes double VLAN tags from packets.
QinQ VLAN tag termination sub-interfaces provide different functions in different scenarios.
4.2.2 Basic QinQ
Basic QinQ is implemented based on interfaces. Basic QinQ allows the device to add the outer
tag to a packet received on an interface. If the received packet carries a VLAN tag, the device
adds the outer VLAN tag to the packet. If the received packet does not carry any VLAN tag, the
device adds the inner VLAN tag and then the outer VLAN tag.
, enterprise A has two branches that connect to the carrier network
through PE1 and PE2 respectively.
Huawei AR530&AR550 Series Industrial Switch Routers
Configuration Guide - Ethernet Switching
4 QinQ Configuration
Issue 01 (2014-11-30)
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