ZyXEL Communications P-660HW-Tx v3 Support Notes page 47

Service
FTP
Telnet
SMTP
DNS (Domain Name Server)
www-http (Web)
Configure a PPTP server behind SUA
Introduction
PPTP is a tunneling protocol defined by the PPTP forum that allows PPP
packets to be encapsulated within Internet Protocol (IP) packets and
forwarded over any IP network, including the Internet itself.
In order to run the Windows 9x PPTP client, you must be able to establish an
IP connection with a tunnel server such as the Windows NT Server 4.0
Remote Access Server.
Windows Dial-Up Networking uses the Internet standard Point-to-Point (PPP)
to provide a secure, optimized multiple-protocol network connection over
dial-up telephone lines. All data sent over this connection can be encrypted
and compressed, and multiple network level protocols (TCP/IP, NetBEUI and
IPX) can be run correctly. Windows NT Domain Login level security is
preserved even across the Internet.
All contents copyright © 2008 ZyXEL Communications Corporation.
P-660HW-Tx v3 Series Support Notes
Port Number
21
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47