L2PT:
https://www.juniper.net/documentation/en_US/junos/topics/concept/l2pt-ex-series.html
Layer 2 protocol tunneling (L2PT) enables service providers to send Layer 2 protocol data units (PDUs) across the provider’s cloud and deliver them to Juniper Networks EX Series Ethernet Switches that are not part of the local broadcast domain.
L2PT works by encapsulating Layer 2 PDUs, tunneling them across a service provider network, and decapsulating them for delivery to their destination switches.
L2 PDU >>> PE Encapsulate L2 PDU + change the well know Dst Mac@ >>> fwd as multicast traffic to all other PE
When a PE device receives a Layer 2 control PDU from any of the customer PE devices, it changes the destination MAC address to 01:00:0C:CD:CD:D0.
L2PT and QinQ tunneling
http://nextheader.net/2016/09/09/qinq-and-l2pt-on-junos-els/
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