From mboxrd@z Thu Jan 1 00:00:00 1970 Content-Type: multipart/mixed; boundary="===============7672550714669197449==" MIME-Version: 1.0 From: Denis Kenzior Subject: Re: PPP connection to a private APN Date: Fri, 09 Aug 2013 09:24:36 -0500 Message-ID: <5204FBA4.6040809@gmail.com> In-Reply-To: List-Id: To: ofono@ofono.org --===============7672550714669197449== Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Hi Etienne, > > So we managed to solve our problem, we found out how to connect to a priv= ate > apn, but we have some questions to clear things up. > > We compared the sequence of AT commands sent by ofono and by network mana= ger > for the same modem (Telit HE910). > One difference is during the activation of the context : > > - ofono uses the 'AT+CGDATA=3D"PPP",' > the driver used by the telit is the atmodem. This command doesn't appear = in > the documentation for the Telit HE910, but it still replied OK. However in > the dumps from ppp, we saw that the DCE does not ask for any authenticati= on > protocol. So the modem doesn't send its credentials, and the DCE eventual= ly > forces a deactivation. > > - network manager used 'ATD*99***#' > With this command, the DCE asks for an authentication protocol. The modem > then sends its credentials and the connection is completed. > > > I am not quite sure why the first command does not work while the second > does and I am very interested in having an explanation if you have one. > Should we use another driver than the atmodem ? one that uses the ATD com= mand ? > So in theory the ATD*99... variation is a legacy context activation = command. It is described in 27.007 Section 10.2.1.1 Request Packet = Domain service 'D'. It is supposed to be superseded by AT+CGDATA, but = many manufacturers have not updated their firmware properly. oFono = supports both, you might need to set a quirk if one is preferred over = the other. > > Another topic is the authentication protocol. By default the Telit HE910 > uses PAP which is not handled by ofono. > I started to implement it in gatchat/ppp_auth.c it is not quite perfect > because it does not ask to do CHAP before falling back to PAP but if anyo= ne > is interested i would be glad to share the code. > We then found out that there is a custom AT command for the Telit HE910 t= hat > allows you to set the authentication protocol to use : AT#CGAUTH=3D[0,1, = or 2] > I added it in plugins/telit.c in the post_online function and stopped > working on PAP. (I am using the telit rework patch provided by Jonas Bonn= on > the 4th of April) Does this work with CGDATA? If that is the case it might explain why = CGDATA does not ask for authentication. You can enable this command = inside drivers/atmodem/gprs-context.c with the appropriate OFONO_VENDOR = handling as well. Patches are always welcome. > > At the moment i just modified the source with these modifications, and it > works nice. > No problem. Regards, -Denis --===============7672550714669197449==--