Hi Steven, > >>>>>>>> I have a little question just as the title said? > >>>>>>>> In Ofono how to connect PPP to Linux socket, when we receive > >>>>>>>> packet from network, how the packet go through the kernel to > >>>>>>>> application？ > >>>>>>>> > >>>>>>>> modem -->PPP-->? --> linux kernel(network part)--> socket --> > >>>>>>>> application? > >>>>>>> it is more like this: > >>>>>>> > >>>>>>> modem -> TTY -> PPP -> TUN/TAP -> Kernel Net-Stack -> socket -> > >>>>>>> application. > >>>>>>> > >>>>>>> With the TTY being in kernel, the PPP being in userspace, and > >>>>>>> TUN/TAP etc. begin in the kernel again. > >>>>>>> > >>>>>>> A future enhancement is to use the kernel PPP layer, but we > >>>>>>> haven't gotten there yet. > >>>>>> I am interested to know how could we use kernel PPP layer instead > >>>>>> of gatppp. Shall we add this item into our TODO? > >>>>>> > >>>>> Maybe you can reference to RILD in Android, it used kernel PPP. > >>>> Thanks. Will take a look then. > >>> This information is a good start point. > >>> http://www.devdiv.net/viewthread-26543 > >>> > >>> But only for Chinese people:( > >> Thanks. I have read this before. ;-). The original article is from > >> maxleng's blog: > >> > >> http://blog.csdn.net/maxleng/archive/2010/05/10/5576509.aspx > >> > >> However, it's just a big picture about phone stack in Android. It said > >> nothing about how Android works with kernel PPP layer. > > > > could be that Andoid uses the kernel PPP and also uses pppd for it. We > > are not using pppd on purpose since it is the wrong piece for an > > embedded phone solution. We are not using the kernel PPP part, because > > we haven't gotten around that yet. It also only works when having real > > TTY devices. > I don't think using pppd is a wrong piece for embedded phone, if we > using pppd, we can ease the ppp part of ofono and also support full ppp > functionalities, such as auth method(plain text, pap, chap, eap and so on)
for a mobile telephony stack, pppd is wrong. Once you understand how 3G missuses PPP for IP and PDP context setup, you see what I mean ;) > If your multiplexer runs in userspace then you also have > > the problem that you don't have a real TTY. And using a PTS, then you > > can just run PPP also in userspace. > > A little question, if we runs multiplexer in kernel space, can we using > kernel ppp part? Yes, we could. We have a kernel multiplexer, but not tested or integrated it with oFono or real hardware. Regards Marcel _______________________________________________ ofono mailing list [email protected] http://lists.ofono.org/listinfo/ofono
