Re: Recent fragility with if_wi, 802.11 adhoc/wep, and Tiger

Sam Leffler wrote:
> Michal Mertl wrote:
> > Robert Watson wrote:
> > 
> >>I fairly regularly use 802.11 adhoc with WEP to communicate between my 
> >>6.x/7.x FreeBSD notebook using if_wi, and my Apple PowerBook running Mac 
> >>OS X Tiger.  A few days ago, when I updated from a June to a July HEAD 
> >>revision, this became quite "fragile".  Specifically, I often find that 
> >>the Mac can't send to the FreeBSD box (ARP fails, etc), and that sometimes 
> >>it will give an error when I ask it to re-connect to the ad hoc network. 
> >>I find that if I ifconfig down/up if_wi, and likewise turn off and on the 
> >>wireless on the PowerBook, it seems to recover.  I've not had a chance to 
> >>really try and diagnose this at all -- i.e., does tcpdump show packets on 
> >>either end, 802.11 state machine, etc.  I was wondering if anyone else has 
> >>seen this problem, though.
> > 
> > 
> > Yes, I'm also experiencing similar problems. The problems seem to happen
> > also with different wireless cards and without wep. They were reported
> > by Johann Hugo on 14th in an email titled "ath hostap - clients
> > assosiated, but no comms" too.
> > 
> > Another problem with WiFi which Johann reported long time ago is that
> > bridging on atheros (only?) AP works really bad. I get very varying ping
> > response (50 - inf. ms). Sometimes it seems the packets get queued
> > somewhere - after some time I receive several replies at once.
> 
> I routinely bridge ath cards (a wide variety) with bge using bridge and 
> see no problems.  I get ~36 Mb/s in 11a w/ superg features and ~28 Mb/s 
> w/ basic stuff (what you find in RELENG_6).  ping times are what you'd 
> expect (<1ms).

I'm sorry, I was too brief in the description of the problem. It's the
bridging on the card which works slow.

I run an ath card in hostap mode and several wireless clients connect to
it and are on the same IP network. The ping from one client to another
is slow yet both ping the AP fine. I think that in this situation the
bridging is done by ath (in HAL?) and configured by 'ifconfig apbridge'.

Michal