CLI Reference Guide-R04

Table Of Contents
Chapter 22
| VLAN Commands
Configuring L2PT Tunneling
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switches carrying this traffic across the service providers network treat these
encapsulated packets in the same way as normal data, forwarding them across
to the tunnel’s egress port. The egress port decapsulates these packets, restores
the proper protocol and MAC address information, and then floods them onto
the same VLANs at the customers remote site (via all of the appropriate tunnel
ports and access ports
21
connected to the same metro VLAN).
The way in which L2PT processes packets is based on the following criteria – (1)
packet is received on a QinQ uplink port, (2) packet is received on a QinQ access
port, or (3) received packet is Cisco-compatible L2PT (i.e., as indicated by a
proprietary MAC address).
Processing protocol packets defined in IEEE 802.1ad – Provider Bridges
When an IEEE 802.1ad protocol packet is received on an uplink port (i.e., an
802.1Q tunnel ingress port connecting the edge switch to the service provider
network)
with the destination address 01-80-C2-00-00-00,0B~0F (C-VLAN tag), it is
forwarded to all QinQ uplink ports and QinQ access ports in the same S-
VLAN for which L2PT is enabled for that protocol.
with the destination address 01-80-C2-00-00-01~0A (S-VLAN tag), it is
filtered, decapsulated, and processed locally by the switch if the protocol is
supported.
When a protocol packet is received on an access port (i.e., an 802.1Q trunk port
connecting the edge switch to the local customer network)
with the destination address 01-80-C2-00-00-00,0B~0F (C-VLAN), and
L2PT is enabled on the port, the frame is forwarded to all QinQ uplink
ports and QinQ access ports on which L2PT is enabled for that protocol
in the same S-VLAN.
L2PT is disabled on the port, the frame is decapsulated and processed
locally by the switch if the protocol is supported.
with destination address 01-80-C2-00-00-01~0A (S-VLAN), the frame is
filtered, decapsulated, and processed locally by the switch if the protocol is
supported.
Processing Cisco-compatible protocol packets
When a Cisco-compatible L2PT packet is received on an uplink port, and
recognized as a CDP/VTP/STP/PVST+ protocol packet (where STP means
STP/RSTP/MSTP), it is forwarded to the following ports in the same S-VLAN:
(a) all access ports for which L2PT has been disabled, and (b) all uplink
ports.
21. Access ports in this context are 802.1Q trunk ports.