Connecting to Google Cloud Platform Dedicated Interconnect
Internet2 offers both a layer 2 and a layer 3 connectivity option.

Layer 2 Google Cloud Platform Dedicated Interconnect Connection
The layer 2 option consists of layer 2 VLANs connecting the campus routers to routers inside the Google cloud. The campus and Google exchange routes via BGP.

Layer 3 Google Cloud Platform Dedicated Interconnect Connection
With the layer 3 option, Internet2 creates an L3VPN unique for each campus. The L3VPN BGP peers with Google and the campus, in turn, BGP peers with the L3VPN. The regional network, if any, passes the VLANs through between the campus and Internet2. One advantage of this option will be discussed further below.

Additional Layer 3 Connectivity

Another advantage of the Layer 3 option is the possibility of connecting to other Google regions and other cloud service providers. In this case, the Internet2 L3VPN peers with the additional sites/providers and the campus simply continues to peer with the L3VPN over the existing VLANs. Doing this with Layer 2 would require possibly many additional VLANs connecting the campus to provider routers.