NM refresh list issues

Hi all:

I'm running NM 0.8 on a Dell Studio 1555 Laptop with Ubuntu 10.04, using
the Broadcom STA wireless driver.  I regularly run between home and the
office. I usually don't hibernate, I just suspend by closing the lid and
go, and reopen the lid when I get to the  other location.  When I get
there, invariably the list of WIFI networks displayed by left-clicking
the NM icon is the OLD list.  The only way I can get it to refresh to
the networks in the NEW location is to disable WIFI, re-enable it, and
(usually) manually select the new network, which should be automatic,
but usually isn't, for whatever reason.  This could be a Broadcom driver
issue, but I doubt it, because a prior Toshiba laptop has similar

I asked this question previously, but at that time the problems were
attributed to a known bug with suspend possibly affecting upgrades to
Ubuntu from prior versions, and also possibly 64-bit Ubuntu (which I was
running before).  

Since then I have downgraded to i386 (to solve flash video problems with
64-bit Ubuntu) and have done a fresh install from scratch.  I still have
the same issues.  So here are the questions:

1) I understand (from discussion on this list) that NM only refreshes
its network list every 2-5 minutes.  This seems unreasonably slow to me,
especially when the connected AP is *no longer* connected.  Does
searching for networks draw additional power (seems like a receive-only
function to me) or significant CPU bandwidth?  Is there some reason it
doesn't search and update this list more often, say every 30-60 seconds?
The Wiki says only that NM attempts to scan "in a manner that impacts
the card the most", whatever that means.

2) I know suspend/hibernate is tricky, all the more reason it should NOT
be relied on to operate properly in all cases.  But if a connection is
lost (regardless of suspend/hibernate status), should that not again
trigger an immediate search for networks?  If the connection to the
current AP is lost, then obviously the environment has changed.  Maybe
one preferred access point has gone down, but maybe a backup hub is
available. Or maybe the laptop has moved. Should NM not automatically
refresh the list, and try to connect to another available auto access
point?  By the same token, if if finds *NO* Wifi networks (like driving
through Nevada, or the manual WIFI switch is off) or no *previously
used* networks (like in a new hotel room), it could shut the receiver
down and only power it up to rescan every 5-15 minutes to save battery,
or even less frequently.  But it's first reaction on losing a connection
SHOULD be to look for another.

3) In the interest of user-friendliness, should there not be an option
to immediately "refresh available networks list" on the main menu?
Having to disable/enable WIFI to effect this refresh of the network list
is both counter-intuitive to new users and extra work for everybody.  In
the Wiki, it says that "clicking on the applet will initiate a scan
request."  Either that does not work, or the list is displayed before
the scan is complete (I don't know how long a scan takes, seconds?
less?), otherwise I would not see old info displayed as I always do.
Even if the claimed action in the Wiki were true, it would be bad
interface design and counter-intuitive, unless it also displayed a
"searching" dialog until the list is refreshed, or refused to display a
list that is not confirmed by the current scan.  Then people would know
for sure that a real and current scan is actually happening, and not
just displaying cached data, which is apparently happening now.

4) The relationship between the various connections listed in "edit
connections" is anything but clear.  Is there a priority in which "auto"
connections are tried (Wiki says the last WIFI used is first, but what
order after that?)  Is a wired connection always preferred over a Wifi,
over a broadband, etc?  Are there ways to adjust those preferences or
priorities?  A help button here would go a long way, since the man pages
for "networkmanager" and "nm-tool" leave much to be desired. And since
NM is the way we GET to the net, a URL on the "about" page is no
substitute for a little internal/local documentation somewhere.   

It seems to me that in the interest of making networking "just work", NM
needs to take more of a "belt-and-suspenders" approach-- rather than
just assume that the intended functionality is always working, it needs
ways that the user can gently "nudge" or confirm it when it isn't. 

Sorry if this sounds like a rant-- it really is intended to be
constructive.  I appreciate all you have done to date-- I just wish NM
delivered a little better on its promise of "just working".  

Matt Warnock <mwarnock ridgecrestherbals com>
RidgeCrest Herbals, Inc.

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