ZyXEL Communications USG 2000 User Manual
Chapter 13 Interfaces
ZyWALL USG 2000 User’s Guide
335
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:
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.
environments. It sets up two sessions.
1
The first one runs on TCP port 1723. It is used to start and manage the second
one.
one.
2
The second one uses Generic Routing Encapsulation (GRE, RFC 2890) to transfer
information between the computers.
information between the computers.
PPTP is convenient and easy-to-use, but you have to make sure that firewalls
support both PPTP sessions.
support both PPTP sessions.