The embodiment of the invention relates to a point-to-multipoint layer 2 element network extension on a layer 3 network. Techniques are disclosed for session-based routing within an
OSI model L2 network extended over an L3 network. The L2 network connects the first
client device to the first
router and the second
client device to the second
router. And the L3 network is connected with the first
router and the second router. A first router receives an L2 frame from a first
client device destined for a second client device. The first router generates an L3 packet including an L3 header specifying L3 addresses of the first router and the second router, a first portion of
metadata including L2 addresses of the first client device and the second client device, and a second portion of
metadata including L3 addresses of the first client device and the second client device, and forwarding the L3 packet to the second router. The second router restores the L2 frame from the
metadata and forwards the L2 frame to the second client device.