Cloud Interconnect enables you to connect your infrastructure to Google, via enterprise-grade connections to Google’s network edge. Connecting with Cloud Interconnect will enable your infrastructure to connect to Google Cloud Platform with higher availability and lower latency connections.
Cloud Interconnect links can be used to access any Google Cloud Platform resource like Google Compute Engine, Google Cloud Storage, Google BigQuery, etc. You can even extend your private network into your private Compute Engine network over Cloud Interconnect links by using a VPN tunnel between the networks.
Google also supports direct connections to your network through Direct Peering.