-----Original Message----- From: owner-hecnet at Update.UU.SE [mailto:owner-hecnet at Update.UU.SE] On Behalf Of Paul_Koning at Dell.com Sent: 22 June 2012 22:25 To: hecnet at Update.UU.SE Subject: Re: [HECnet] DECnet User Mode Router - Encapsulation Formats On Jun 22, 2012, at 4:07 PM, Rob Jarratt wrote: DDCMP over some kind of serial line? Would need appropriate hardware and driver code to work against that. DDCMP over sync, yes. But DDCMP also works on an async line, and that just requires protocol code that can talk to a raw mode TTY device. That would work for what I need -- I have async DDCMP on my PRO-380 running RSTS, and in fact it's a standard feature of some of the PDP11 DECnet products. (I'm not sure if it was ever official in DECnet/E, but the machinery is there in the latest versions of the kernel.) paul Hmmm, so if we can use async serial then we have a chance to add that to the router once I have had a chance to do the main part. It would be good to do something like that. I don't know enough about DDCMP yet to know what the implications are (can it work with a Version 2 router for example?). Regards Rob