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Wr1500, Appendix d, Pptp – ParkerVision WR1500 User Manual

Page 175

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WR1500

4-Port Wireless DSL/Cable Router

®

177

Appendix D

PPTP

What is PPTP?
PPTP (Point-to-Point Tunneling Protocol) is a Microsoft proprietary protocol (RFC 2637 for

PPTP is informational only) to tunnel PPP frames.

How can we transport PPP frames from a PC to a broadband modem over Ethernet?
A solution is to build PPTP into the ANT (ADSL Network Termination) where PPTP is used

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 drawback of this solution is that it requires

one separate ATM VC per destination.

PPTP and the WR1500 Wireless Router
When the WR1500 Wireless Router is deployed in such a setup, it appears as a PC to the

ANT. In Windows VPN or PPTP Pass-Through feature, the PPTP tunneling is created from

Windows 95,98 and NT clients to an NT server in a remote location.

The pass-through feature allows users on the network to access a different remote server

using the WR1500 Wireless Router’s Internet connection. In NAT mode, the WR1500

Wireless Router is able to pass the PPTP packets to the internal PPTP server (i.e. NT server)

behind the NAT. Users need to forward PPTP packets to port 1723 by confi guring the server

in Menu 15.2 - Server Set Setup.

In the case above as the remote PPTP Client initializes the PPTP connection, the user must

confi gure the PPTP clients. The WR1500 Wireless Router initializes the PPTP connection

hence; there is no need to confi gure the remote PPTP clients.