On Wed, 16 Nov 2005, Duncan Sands wrote: > The problem here is the way ATM connections are opened: you specify > a device number, called the interface number, as well as some other info. > Alternatively, you can specify ATM_ITF_ANY instead of a device number, > and all devices will be queried until one is found that is prepared to > open the connection. > > With the speedtouch USB modems, the problem people usually see is: > > (A) for normal people, the modem is the only ATM device (and there's > only one modem). Thus this is ATM device zero. > > (B) people connect using pppd; pppd doesn't support ATM_ITF_ANY, so > most people specify that the connection should be to device number 0. > pppd is usually run from a hotplug or init script. > > (C) at some point the modem spontaneously disconnects and reconnects > (surprisingly common with some motherboards). pppd takes several seconds > to understand that ATM device 0 has died; until it understands this, it > keeps a connection open, which means that the ATM device hangs around. > The "new" modem (= old one reconnected) creates a new ATM device, which > is given device number 1, because number 0 is still being used by the > old device. > > (D) a new instance of pppd is launched from a hotplug script, or the > old instance of pppd tries to open a new connection once it understands > that the old connection has died. It tries to connect to device 0, but > there is no longer any device 0, only device 1, so the connection attempt > fails. > > (E) the user notices that there is no internet connection and wonders why. > The user runs pppd by hand - and it still fails to connect (no device 0). > Eventually the user gives up and reboots the machine.
This sounds like an application problem. Isn't it possible to add support for ATM_ITF_ANY to pppd? It's a mistake to used fixed identification numbers in a situation where devices can be added or removed at random and the numbers changed accordingly. Alan Stern ------------------------------------------------------- This SF.Net email is sponsored by the JBoss Inc. Get Certified Today Register for a JBoss Training Course. Free Certification Exam for All Training Attendees Through End of 2005. For more info visit: http://ads.osdn.com/?ad_id=7628&alloc_id=16845&op=click _______________________________________________ linux-usb-devel@lists.sourceforge.net To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
