>2) People have done SLIP over IrDA; I'm surprised PPP doesn't work.  
>   Usually TCP tunes the parameters over time so that half duplex is
>   properly accommodated.

SLIP has absolutely no negotiation; you just send an IP packet with
(IIRC) two framing bytes.  Where PPP gets hung up is the negotiation;
the LCP negotiation never completes.  I believe the problem was
from the PPP daemons on both side sending responses before the
minimum turnaround time had elapsed.

>3) It -is- possible to run stock PPP over the IR port, essentially directly.
> 
>   (a) In the IrDA "1.0" mode, that is, async over serial a serial port, the
>       only "driver" required is usually to silence the receiver while
>       transmitting to prevent hearing what you send (not all IR transceiver
>       chips have this property; others squelch their own receivers during
>       transmission).

I am skepical; I tried this, and it lost severely.  Do you know anyone that
actually made it work?

>4) That being said, I think you ought to stick to the standard IrDA 
>   protocols.  Basically, the whole -point- is intercommunication with other
>   systems.  And don't forget the range of devices out there already and
>   coming down the pipe with IrDA built in: Palm Pilots, Digital Cameras,
>   cell phones, all WinCE PDAs, Printers, Pagers, etc.

I would agree with this.

>   Oh, and I don't want to forget to mention that a top-level IrDA protocol,
>   IrDA-OBEX has been chosen by the Bluetooth group as one of their
>   top-level data exchange formats.

Of course, the problem with Bluetooth now is that it's too proprietary :-(

--Ken