Fast connect after losing Link

[Jouni Malinen]

On Wed, Feb 03, 2016 at 03:15:59PM -0800, Naveen Singh wrote:
> I guess short amount of time is quite debatable. Just the wifi medium
> access time could vary from  scenario to scenario. There are many
> things that needs to be considered:
> 
> 1) We need to notify connman that L2 level link is gone but
> wpa_supplicant is trying to get connected back.

Or alternatively not notify connman at all before wpa_supplicant has
tried and failed to reconnect.. That said, I have no issues in adding a
separate notification that makes it clear there is an attempt to
reestablish connection to the same ESS as a noted that IP address etc.
should not yet be dropped.

> 2) With this notification connman would let applications know that
> data traffic is not feasible at this time but it is not a disconnect
> notifications

Does that capability exist today and how do applications use that
information? I'm assuming this would leave the netdev with IP
address(es) and routing in place.

> 3) When wpa_supplicant is done with all its attempt (including current
> BSSID and any other BSSID), it does a final notification that
> connection is lost

All its attempts to _this ESS_. Yes, sounds fine to add such a
notification.

> 4) connman or user level application takes control from here.

That depends on the use case.. If configured to do so with multiple
enabled network profiles, wpa_supplicant will try to find another ESS as
an alternative. Anyway, if connman does not want such behavior, it can
enable only a single network profile.

> So to make it robust I think we need two different notification and
> that needs to be handled differently in connman.

Agreed.

-- 
Jouni Malinen                                            PGP id EFC895FA