ZyXEL Communications ZyWall USG 2000 User Manual page 224

Chapter 10 Interfaces
• Gateway - The interface provides the same gateway you specify for the
interface. See
• DNS servers - The interface provides IP addresses for up to three DNS servers
that provide DNS services for DHCP clients. You can specify each IP address
manually (for example, a company's own DNS server), or you can refer to DNS
servers that other interfaces received from DHCP servers (for example, a DNS
server at an ISP). These other interfaces have to be DHCP clients.
It is not possible for an interface to be the DHCP server and a DHCP client
simultaneously.
WINS
WINS (Windows Internet Naming Service) is a Windows implementation of
NetBIOS Name Server (NBNS) on Windows. It keeps track of NetBIOS computer
names. It stores a mapping table of your network's computer names and IP
addresses. The table is dynamically updated for IP addresses assigned by DHCP.
This helps reduce broadcast traffic since computers can query the server instead
of broadcasting a request for a computer name's IP address. In this way WINS is
similar to DNS, although WINS does not use a hierarchy (unlike DNS). A network
can have more than one WINS server. Samba can also serve as a WINS server.
PPPoE/PPTP Overview
Point-to-Point Protocol over Ethernet (PPPoE, RFC 2516) and Point-to-Point
Tunneling Protocol (PPTP, RFC 2637) are usually used to connect two computers
over phone lines or broadband connections. PPPoE is often used with cable
modems and DSL connections. It provides the following advantages:
• The access and authentication method works with existing systems, including
RADIUS.
• You can access one of several network services. This makes it easier for the
service provider to offer the service
• PPPoE does not usually require any special configuration of the modem.
PPTP is used to set up virtual private networks (VPN) in unsecure TCP/IP
environments. It sets up two sessions.
The first one runs on TCP port 1723. It is used to start and manage the second
1
one.
The second one uses Generic Routing Encapsulation (GRE, RFC 2890) to transfer
2
information between the computers.
PPTP is convenient and easy-to-use, but you have to make sure that firewalls
support both PPTP sessions.
224
IP Address Assignment on page 221.
ZyWALL USG 2000 User's Guide