There are several components used to integrate the VM-Series with Network Connectivity Center.
Network Connectivity Center – Hubs and Spokes
Network Connectivity Center leverages a hub-and-spoke model to provide end-users a single place to manage global connectivity across various networks. The hub is a global resource that connects attached spokes with a simple and singular connectivity model. The Network Connectivity Center hub creates a full mesh networking model between the VM-Series and all other connected spokes. The VM-Series connects to the hub as a router appliance spoke.
Google Cloud Router
The VM-Series integrates with Network Connectivity Center by establishing BGP peering relationships with a VPC’s Cloud Router. This relationship enables full route propagation between remote networks and the Google Cloud VPC fabric routes.
Once the peering relationship is established between the Cloud Router and the VM-Series, routes from remote networks, Google Cloud VPCs, and the VM-Series are exchanged. If the VM-Series firewalls are deployed within the same spoke, the hub advertises the same prefixes to all of the firewalls. This behavior enables equal-cost multipath (ECMP) for hub to firewall traffic. If you prefer to isolate traffic flows to dedicated firewalls, the VM-Series should be placed in separate spokes with different ASNs.
The VM-Series can be used to secure traffic from remote networks to Google Cloud VPCs. The following outcomes are achieved through the integration with Network Connectivity Center:
In this topology, VM-Series firewalls are deployed across different zones within the same region. The firewalls are connected as a single spoke to the Network Connectivity Center hub and have a BGP session established with the VPC’s Cloud Router. From on-premises, IPsec tunnels are created and terminated on each firewall. Routes to and from the remote network and the VPC are exchanged through the VM-Series and Cloud Router. The VM-Series firewalls are advertising the same prefixes and MED values to take advantage of Google Cloud’s ECMP functionality. The use of ECMP provides redundancy and load distribution among the zonally distributed firewalls.
The architecture shows two VM-Series pairs (within the same VPC) distributed across two Google Cloud regions. Each firewall pair is a separate spoke connected to the Network Connectivity Center hub. The Cloud Router BGP peers with its respective regional firewall pair. Routes from the remote sites are advertised to the VM-Series firewalls via the Cloud Router. The Cloud Routers themselves exchange routes to provide full mesh connectivity.
