Re: One more question about device activation (trunk)

[Dan Williams <dcbw redhat com>]

On Sat, 2007-09-29 at 17:59 +0200, Helmut Schaa wrote:
> Am Sa 29 Sep 2007 07:10:59 CEST schrieb Dan Williams <dcbw redhat com>:
> 
> > On Fri, 2007-09-28 at 08:54 +0200, Helmut Schaa wrote:
> >> Hi,
> >>
> >> just stumbled across an issue while playing around with wireless connections
> >> in KNM.
> >>
> >> Why does NM require specific_object to be set when connecting to a wireless
> >> network? Shouldn't the wireless and security settings suffice? What  
> >>  if I want
> >> to connect to a hidden network where no AP is available yet?
> >
> > The reason for specific_object is this...  A connection doesn't
> > necessarily _have_ to correspond to a specific AP.  Therefore, the
> > choice is left up to the user client which specific AP to apply the
> > connection to (as long as that AP is still compatible with the
> > connection).  For example, say you have two APs with the same SSID, but
> > one is bg and one is b-only.  Maybe the applet wants to connection to
> > the bg one specifically to get higher speed, who knows.
> 
> But the setting "802-11-wireless" has a member "bssid". If the  
> frontend wants to connect to a specific AP it should be sufficient to  
> pass the AP's BSSID, not?

No.  there are cases where a single BSSID can drive _two_ SSIDs, one
broadcast and one hidden.  There _must_ be an SSID passed, otherwise the
association/authentication process cannot complete.  To uniquely
identify the network to which you wish to connect, you must specify the
tuple of (SSID, BSSID).  Most of the time you can fudge the BSSID or
pick it up from scan results, but that's not always the case.

It's also about flexibility.  Maybe you want to only associate with APs
of a specific SSID that support G-rate.  Maybe there are more than one.
etc.

Dan

> > That said, you've got a point with hidden networks.  We'll probably have
> > to allow a null specific_object for wireless and regard specific_object
> > as a hint only.
> 
> Right :)
> 
> >> In my opinion NM should (if no AP is specified) try to find one in   
> >> its AP-list
> >> which fits best the connection's settings and use this one (for hidden
> >> networks of course no AP should be used). I think there was some code in NM
> >> which had this behaviour before?
> >
> > Yes, this is how it should work.
> 
> Regards,
> Helmut
> 
>