Re: wireless options not implemented

[Dan Williams <dcbw redhat com>]

On Tue, 2010-06-01 at 07:46 -0700, Sean D'Epagnier wrote:
> I really need to set the wireless bit rate otherwise the packet loss
> is so high I cannot use the network.   I can  get by for now by
> issuing manually "iwconfig wlan3 txpower 1M" often

That is clearly a driver problem that should probably be fixed in the
driver; pounding the TX power and bitrate is a pretty fragile hack.

Do you mean "1W" there instead of "1M"?  Or do you really mean "iwconfig
wlan3 rate 1M"?

> I noticed in finish_setup in page-wireless.c the band, channel, tx
> power, and rate widgets are purposefully hidden so they cannot be
> used.   I removed the code hiding them, and they work in the GUI, but
> they still don't actually change wireless settintgs.   Does anyone
> know why they are not implemented and how to make them work?

They weren't implemented yet because most people didn't have a use for
them, or the supplicant (which is used to control all network settings)
didn't support them on a per-network basis.  TX power also used to be
very inconsistently implemented between different drivers and thus is
often useless or not even supported by a driver, and the user has no
idea if it is supported or not.  Drivers also do not reliably implement
allowed power level reporting, which doesn't help NM determine what the
right levels are for each driver.

Second, we don't want to be using WEXT at all really, we want to be
using cfg80211 instead.

Jirka has just added support for the band/channel setting to git master
for Ad-Hoc connections, but we can't use that yet for
infrastructure-mode connections because only wpa_supplicant 0.7.x has
that capability at this time.

We probably do want some kind of TX Power configuration, but that would
likely be a choice between "Auto" (ie allow power saving and auto TX
Power adaptation if the driver supports it), "Maximum power" (use the
max supported level the driver reports, if it does report anything).

But in reality, what you probably want to do at this time to work around
the broken driver that you're using is:

1) report the bug upstream to help get the driver fixed
2) as long as initial association succeeds, you can use a dispatcher
script (man NetworkManager for more details) to set the bitrate manually
when the connection is activated

But again, not all drivers support locking in a TX power and a bitrate,
and may ignore whatever you've set.  That could be the case for you
since you seem to need to run iwconfig often.  In the end, the best
thing to do is to fix the driver.

Dan