On Linux there is support for special Radio Amateur radio network protocol called AX.25 (and couple more or less related ones). My pondering is: What kind of USB device class profile specification to bend so that I could make a packet oriented radio data modem connectable to these network layers ? I do think that it needs to be some sort of "Communications Device Class" thing, but what kind of ? I really do not want to put virtual serial ports and KISS encapsulation in there... (Those not familar with Radio Amateur protocols, KISS is variation of SLIP with a hook to handle couple link-layer control functions, plus multiplexing multiple devices on single serial port.) On USB CDC specification part 4.7 there is a table of "Data Interface Class Protocol Codes" -- and there code 31h: "HDLC" would probably be what engineer orders for all manner of radio amateur data protocols. (That use packets to begin with.) This is one of "ISDN device" subclasses, which may cause interesting mixup when plugged in.. Another could be to bend "CDC ECM" -- to treat the devices as if they are Ethernet. Third possibility is to bend the specification called "CDC WMC1.1"; "Wireless Mobile Communications device", which these sort of are... Pick either "LAN frame", or some "MDLM". What I would prefer to avoid like a plague is using "this is proprietary" type tagging. Any ideas ? /Matti Aarnio -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html