Hi, I've received many mails about running PPP over/instead of IrDA over the years, so now you have a chance to do something about it. I've just tested PPP over IrCOMM at 4Mbps and the performance is pretty bad. The throughput is about 130 Kbytes/s compared to 340 Kbytes/s using IrLAN. I think the main reason for this is that "normal" PPP is doing Async HDLC and CRC which costs way to much. CRC is not even necessary since IrDA is reliable. So the only way to avoid this is probably to implement a synchronous irda_ppp.c driver that runs directly on top of a IrTTP connection. PPP _must_ run over IrTTP to allow for other IrDA traffic as well. This is what Clarinet (http://www.clarinetsys.com) wants to do in their IrPPP proposal. They also allow for negotiation so that IrPPP can do AHDLC and CRC if the remote stack needs it (as the current Linux impl. do ;-) Notice however that IrPPP is not (yet) an IrDA standard, but since it runs on top of IrTTP then it really don't need to be (although it might be if we do it). Clarinet is also pushing IrPPP so this will not be a Linux only thing. There are good reasons to run PPP over IrDA, and most of all is probably the easy and automatic configuration of the network parameters. It can also be pretty fast since you avoid the Ethernet overhead (14 bytes) needed by IrLAN. So if you want a "little" project, then I would expect PPP over IrDA to be pretty exciting. If you're interested then I can send you the IrPPP propoal + put you in contact with Clarinet. Personally I think it would be really exciting to do it, mainly because IrLAN is so hairy, so an alternative (that performs just as well) would be great. I would have done it myself if I didn't have so much else to do! -- 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/ ///
