The name or IP address of a proxy-based firewall.
This property specifies the IP address, DNS name, or host name of a proxy allowing traversal of a firewall. The protocol is specified by FirewallType: Use FirewallServer with this property to connect through SOCKS or do tunneling. Use ProxyServer to connect to an HTTP proxy.
Note that the provider uses the system proxy by default. To use a different proxy, set ProxyAutoDetect to false.