Alcatel Speed Touch Wireless, User Manual

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What is Tunneling
Tunneling applied to
the STWireless
Result of PPTP
tunneling
Supported (W)LAN
Protocols
7 Data Services - PPPoAĆtoĆPPTP Relaying
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3EC 17766 AAAA TCZZA Ed. 01
7.6.1 PointĆtoĆPoint Tunneling
Tunneling is a technique that allows to transport certain protocols
over a network, which is not designed for that purpose.
Example : IPX Packets can be wrapped in IP, ready to be routed
over an IP network.
At the destination, the IPX packets are decapsulated and made
available in their original format again.
Tunneling applied to the STWireless implies that:
"
Tunnels have a local scope.
Indeed, tunnels are established between two peers on the
local IP network: local PCs initiate tunnels, the STWireless
terminates these tunnels.
"
IP tunnels are established and released for the duration of a
session.
"
The protocol carried inside the tunnels is PPP. However,
various protocols can be carried inside the PPP frames.
The net result of PPTP tunneling is that PPP frames can cross
the local Ethernet segment between the STWireless and the client
computer and vice versa.
This would otherwise not be possible as PPP is designed to run on
pointĆtoĆpoint connections, e.g. DialĆUp connections, whereas
Ethernet is a shared medium.
Within PPP, all kinds of protocols can be transported.
The PPP/PPTP client, however, is the limiting factor. Some OSs only
allow specific protocols to be transported within PPP tunnels (e.g.
TCP/IP, IPX/SPX, or NETBEUI in case of Window 9x).