Subj : PPPx, LANx activity.
To   : Ferdinand Grassmann
From : David Calafrancesco
Date : Fri Nov 23 2001 03:16 pm

Ferdinand Grassmann wrote in a message to Ian Moote:

FG> Thursday November 22 2001 08:16, you wrote to ALL:

IM> Distributed.Net's RC5 client (usually) knows when the ppp0 (for example)
IM> connection is alive so that it can exchange packets with its server.
IM> How?

FG> Hmm, don't know. :-/

The same way that tools like netstat -a figure it out. There are things that
are affected everytime you bring a network adapter online. It has been a real
long time since I looked into those types of things. A very simple test would
be `netstat -a | grep -i 'PPP0 IP addy' && echo PPP0 is up` wrap it in a wait
loop with some sleeps and it can look every xx seconds.

IM> And along the same lines: Injoy knows when a client wants access to the
IM> Internet. Again, how?

FG> IIRC InJoy sets the default route to a fake IP that is "assigned"
FG> to the serial device it uses for connecting to the Internet. If a
FG> program wants to access a computer that has an IP address not
FG> existing in your (sub-)net, the request is forwarded to this IP
FG> (111.222.111.222 IIRC), and triggers the InJoy DoD feature. So this
FG> is simply a question of routing.

InJoy installs itself as tcpip network driver and ties into the TCPIP stack.
When DoD is active, it simulates the normal connection state as far as the rest
of the system is concerned and caches the requests and when it sees requests
for the external network, dials the connection and sends the packets.

Dave Calafrancesco, Team OS/2
[email protected]

... They got the library at Alexandria, they're not getting mine!
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