UTT Technologies Chapter 12 VPN
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Chapter 12 VPN
12.1
PPTP VPN
The Router supports PPTP feature. PPTP is a VPN tunneling protocol which encapsulates
PPP frames in IP packets for transmission over a public IP network such as the Internet.
PPTP is based on client/server model. The PPTP initiates a PPTP connection to the
server, while the PPTP server accepts the incoming PPTP connection from the client.
PPTP is often used to implement Remote Management VPNs over an IP network (such as
a broadband network), to extend the reach of your Intranet.
12.1.1 Introduction to PPTP Implementation
PPTP is used to encapsulate PPP frames in IP packets for transmission over a public IP
network such as the Internet. The PPTP or server encapsulates the original user packets
inside PPP frames before sending them through a PPTP tunnel over the Internet; while
the peer performs decapsulation firstly, and then forward the original packets to their
intended destinations.
As shown in Figure 12-1, the typical application of PPTP is that some laptop or desktop
computers act as the PPTP devices, that is, some employees in the remote branch offices
or mobile users (traveling employees, telecommuters, etc.) use the Windows built-in
PPTP software to initiate PPTP Sessions; the PPTP server deployed at the head office
accepts the PPTP incoming Sessions from the clients. After a PPTP tunnel has been
established between the PPTP and server, the PPTP server will receive the PPTP packets
from the client firstly, and then perform decapsulation, lastly forward the original packets to
their intended destinations.
Figure 12-1 Typical Application of PPTP