# VPNGw

VPN Gateway is a type of Virtual Network Gateway

Only one VPN Gateway in a VNET.

VPN GW Types:

* Policy Based VPN:
  * supports IKEv1 only
  * use of static routes
* Route Based VPN
  * supports: connection between VNETs, point-to-site connections, multisite connections, coexistence with Azure ExpressRoute Gateway
  * supports IKEv2
  * uses any to any traffic selector
  * can use dynamic routing protocols

VPNGw sizes:

* Basic: 10 sites, 100 Mbps, no BGP support
* VpnGw1/Az: 30 sites, 650Mbps, BGP supported
* VpnGw2/Az: 30 sites, 1Gbps, BGP supported
* VpnGw3/Az: 30 sites, 1.25Gbps, BGP Supported

Required resources:

* In Azure:
  * VNET
  * GatewaySubnet of at least /27
  * Public IP Address (Basic-SKU). Dynamic but it won't change
  * Local Network Gateway
  * Virtual Network Gateway
  * Connection
* On Prem:
  * A VPN device
  * internet routable IPv4 Addresses

HA

* by default the Gateway is deployed as a 2 instances in an active/standby config but only the active one is visible.
* Active/active is also possible

VPN Gateway can act as a failover for ExpressRoute
