Google Cloud Hybrid Connectivity
Google Cloud provides various network connectivity options to meet the needs, using either public networks, peering, or interconnect technologies
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Public Network Connectivity
Standard internet connection can be used to connect Google Cloud with the on-premises environment if it meets the bandwidth needs.
- provides secure, private connectivity using IPSec
- connects on-premises networks to VPC or two VPCs in GCP
- traffic flows via the VPN tunnel but is still routed over the public internet
- traffic is encrypted by one gateway and decrypted by the other
- allows users to access private RFC1918 addresses on resources in the VPC from on-prem computers also using private RFC1918 addresses.
- can be used with Private Google Access for on-premises hosts
- provides guaranteed uptime of 99.99% using High availability VPN
- supports only site-to-site VPN
- supports up to 3Gbps per tunnel with a maximum of 8 tunnels
- supports static as well as dynamic routing using Cloud Router
- supports IKEv1 or IKEv2 using a shared secret
- Peering provides better connectivity to Google Cloud as compared to the public connection. However, the connectivity is still not RFC1918-to-RFC1918 private address connectivity.
- Peering gets your network as close as possible to Google Cloud public IP addresses.
- requires you to lease co-lo space and install and support routing equipment in a Google Point Of Presence (PoP).
- supports BGP over a link to exchange network routes.
- All traffic destined to Google rides over this new link, while traffic to other sites on the internet rides your regular internet connection.
- preferred if installing equipment isn’t an option or would prefer to work with a service provider partner as an intermediary to peer with Google
- connection to Google is via a new link connection installed to a partner carrier that is already connected to the Google network itself.
- supports BGP or uses static routing over that link.
- All traffic destined to Google rides over this new link.
- Traffic to other sites on the internet rides your regular internet connection.
- Interconnects are similar to peering in that the connections get your network as close as possible to the Google network.
- Interconnects differ from peering as they provide connectivity using private address space into the Google VPC.
- For RFC1918-to-RFC1918 private address connectivity, either a dedicated or partner interconnect is required
- provides private, high-performance connectivity to Google Cloud
- requires you to lease co-lo space and install and support routing equipment in a Google Point Of Presence (PoP).
- requires installing a link directly to Google by choosing a 10 Gbps or 200 Gbps pipe and provisioning a VLAN attachment over the physical link
- gives the RFC1918-to-RFC1918 private address connectivity.
- All traffic destined to the Google Cloud VPC rides over this new link.
- Traffic to other sites on the internet rides the regular internet connection.
- Single Interconnect connection does not offer HA and GCP recommends redundancy using 2 (99.9%) or 4 (99.99%) interconnect connections so that if one connection fails, the other connection can continue to serve traffic
- provides private, high-performance connectivity to Google Cloud
- preferred if bandwidth requires are below 10 Gbps or installing equipment isn’t an option or would prefer to work with a service provider partner as an intermediary
- similar to carrier peering in that you connect to a partner service provider that is directly connected to Google.
- supports BGP or use static routing over that link.
- requires provisioning a VLAN attachment over the physical link
- gives the RFC1918-to-RFC1918 private address connectivity.
- All traffic destined to your Google VPC rides over this new link.
- Traffic to other sites on the internet rides your regular internet connection.
Google Cloud Hydrid Connectivity Decision Tree
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