RCA 605 User Manual

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E-DOC-CTC-20051017-0151 v1.0
Chapter 5
Expert Configuration
5.4.8 PPTP-to-PPP Relay
Overview
The PPTP-to-PPP Relay, referred to as "Relay" further in this section, interacts with a 
PPTP tunnelling application installed on the locally attached computers, for 
example Microsoft's Dial-Up Networking.
A typical user-relay interaction scenario is as follows: A PPTP Tunnelling application 
is started on one of the locally attached computers. This application establishes a 
PPTP tunnel to the SpeedTouch™ and is the trigger for the Relay to come into 
action. The Relay chooses a free PPPoA phonebook entry and from then on relays 
all PPP frames sourced by the PPTP application from the tunnel to the virtual 
channel identified by the phonebook entry and vice versa. At the remote end of the 
virtual channel, the BRAS extracts the PPP frames, reconstructs the encapsulated IP 
packets and forwards these to the Internet.
If, at the end of a session, the user disconnects the PPTP application, it destroys the 
tunnel and the Relay subsequently releases the virtual channel. 
Multiple users can initiate/terminate tunnels towards the Relay as long as there are 
free ATM virtual channels on the DSL Line. The maximum number of tunnels may 
however be restricted by DSL provider / ISP provisioning rules.
The SpeedTouch™ Relayed PPPoA page allows you to overview current active relay 
session, currently maintained by the SpeedTouch™.