Setup the ZyAIR as a PPTP Client

- What is PPTP Client?

Microsoft's Point-to-Point Tunneling Protocol (PPTP) is a network protocol that enables the secure transfer of data from a remote client to a private enterprise server by creating a VPN across TCP/IP network. PPTP supports on-demand, multi-protocol, virtual private networking over public networks, such as the Internet.

This implementation of PPTP client is specifically for the French market where Alcatel's ANT (ADSL Network Termination) is deployed. Most, if not all, broadband modems (ADSL and cable modem) are equipped with Ethernet instead of RS-232 because RS-232 is too slow. It is therefore impossible to use them in the same way as the traditional analog modem and ISDN TA. A mechanism is needed to transport the PPP frames from a PC to the broadband modem over Ethernet. Before PPPoE was formalized, Alcatel came up with the idea of building PPTP into their ANT for this purpose.

Instead of using the Internet to transport PPP frames anywhere in the world as originally envisioned, Alcatel's solution uses PPTP only over the short haul between the PC and the modem over Ethernet. For the rest of the connection, the PPP frames are transported with PPP over AAL5 (RFC 2364). The PPP connection, however, is still between the PC and the ISP.

The various connections in this setup are depicted in the following diagram.

The PPTP client feature means the PPTP connection is initialized by the ZyAIR router, so this connection is transparent to the PPTP clients on the network. This eliminates the settings of every clients and does not matter whether the computers on the network are Windows, Macintosh or even UNIX, all that is required is a standard TCP/IP protocol stack. In fact,
users are unaware that they are on a VPN, since the ZyAIR does all the VPN work.

- Setup the ZyAIR as a PPTP client

`Menu 4 - Internet Access Setup` `ISP's Name= ChangeMe` `Encapsulation= PPTP` `Service Type= N/A` `My Login= dean` `My Password= ********` `Idle Timeout= 100` `IP Address Assignment= Dynamic` `IP Address= N/A` `IP Subnet Mask= N/A` `Gateway IP Address= N/A` `Network Address Translation= SUA Only` `Press ENTER to Confirm or ESC to Cancel:`

Key Settings:

Option | Description
Encapsulation | Set 'PPTP' as the encapsulation.
My Login | Enter the login name to login the PPTP server.
My Password | Enter the password associated with the login name above.
IP Address Assignment | Choose 'Dynamic' if the PPTP server provides the IP dynamically, otherwise choose 'Static'.
IP Address | Enter the IP address supplied by the PPTP server if applicable.
Single User Account | Set this field to 'Yes' to enable the Single User Account feature for your ZyAIR. Use the space bar to toggle between 'Yes' and 'No'.

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