Each ISP may provide a set of DNS servers for DNS lookups. This setting
specifies the DNS (Domain Name System) servers to be used when a DNS
lookup is routed through this connection.
Selecting Obtain DNS server address automatically results in the DNS
servers being assigned by the WAN DHCP server to be used for outbound
DNS lookups over the connection. (The DNS servers are obtained along with
the WAN IP address assigned from the DHCP server.)
When Use the following DNS server address(es) is selected, you may
enter custom DNS server addresses for this WAN connection into the DNS
Server 1 and DNS Server 2 fields.
9.1.4 L2TP Connection
L2TP has all the compatibility and convenience of PPTP with greater security. Combine this with
IPsec for a good balance between ease of use and security.