> On 1 Jun 1999, Dag Brattli wrote:
> > I guess that the issue of being char or net device is really about being
> > point-to-point or more like a multiple access MAC layer. IrDA is both and
> > can function in connected reliable, unconnected reliable, connected
> > unreliable, and unconnected unreliable mode. IrDA v2 known as AIR will also
> > support multipoint which is not that easy to put over the TTY abstraction.
>
> What happens if one would want to run PPP over IrDA (or comparable links)
> which requires some formatting before the PPP serial data goes out the
> serial port.
>
> Since PPP hooks into the tty as a line discipline, it would be necessary
> to make a dummy tty-like device, to which PPP would hook in and which
> would then process/format the data. The other end of the dummy-tty would
> connect as a line discipline on the actual physical tty ? That sounds a
> bit complicated, any other ideas on how to do it ?
The way to do this is called IrCOMM and is a serial port emulation protocol
which makes it possible to use all your favorite serial port applications
over an IrDA link. This is the reason we can use pilot-xfer to sync the
Palm Pilot over IrDA even if the pilot-xfer program does not know anything
about IrDA links. It is possible to run PPP over IrCOMM.
Some people does not like the overhead of running PPP over IrCOMM, so they
have proposed a new standard called IrPPP. IrPPP basically just sends the
"raw" PPP frames (hopefully without any CRC) directly over the IrDA link
(IrTTP). Infrared access points are expected to support both IrLAN and
IrPPP in future. I haven't had time to implement IrPPP yet, but it should
be quite easy to fix.
PS. I haven't tried to run IrDA over IrCOMM yet ;-)
-- Dag
-- / Dag Brattli | The Linux-IrDA Project / // University of Tromsoe, Norway | Infrared communication for Linux // /// http://www.cs.uit.no/~dagb | http://www.cs.uit.no/linux-irda/ ///- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.rutgers.edu Please read the FAQ at http://www.tux.org/lkml/