Re: ath(4) and 802.11g speed



Thus spake Daniel O'Connor (doconnor@xxxxxxxxxxxx) [10/03/06 01:00]:
: Sounds like a question for Sam.

Sam?

: Actually one thing.. Is the AP set for g mode or b only?

11g mode only. Specifically, autoselect mode 11g, and is currently running
at OFDM54.

Thus spake JoaoBR (joao@xxxxxxxxxxxx) [10/03/06 01:40]:
: > : > Okay, this has me a bit curious, so I dug into it a bit more:
: > : >
: > : > SSID BSSID CHAN RATE S:N INT CAPS
: > : > linksys 00:06:25:7b:25:3d 6 11M 35:0 100 E
: > : > MYSSID 00:12:17:85:9a:3b 11 54M 39:0 100 E
: > : > wahoo62 00:13:46:47:0f:0e 11 54M 4:0 100 EPS
: > : >
: > : > I'd have thought that a S:N of 39:0 wouldn't be all that weak, no?
: > : > Looking at a post by Sam this past August, he calls 30:0 "very strong",
: > : > though that was for an 802.11b link. I'd think that the higher the
: > : > number, the stronger the signal. Is the above too weak to handle a
: > : > full 54Mbps link?
: > :
:
: generally it is not the signalstrength which let you connect at higher speeds,
: it is the noise level. So you can have a low signal without noise and you may
: connect at high speed and on the other hand you may have a strong signal and
: high noise and the speed is 1Mb or do not connect/associate at all

I've been doing some testing with kismet throughout the night, and I've been
seeing consistant signal strengths around -50 to -60dBm, with noise sitting
pretty consistantly at -96, and its strongest reading (after about six
hours) is -90dBm. At least, if I'm to believe what Kismet is telling me.

This machine is about five feet (albeit through a concrete wall) from the AP.
A wireless laptop that's about twenty feet (again, through concrete) has
connected at 54Mbps without issues.

: > -----
: > ath0: flags=28943<UP,BROADCAST,RUNNING,PROMISC,SIMPLEX,MULTICAST,PPROMISC>
: > mtu 1500 inet6 fe80::20f:b5ff:fe20:71ed%ath0 prefixlen 64 scopeid 0x1
: > inet 192.168.132.146 netmask 0xffffff00 broadcast 192.168.132.255
: > ether 00:0f:b5:20:71:ed
: > media: IEEE 802.11 Wireless Ethernet autoselect <monitor>
: > status: associated
:
:
: tha card default in autoselect is probably 11b so it do not connect at 11g
: until you configure it to
:
: ifconfig mode 11g media OFDM/54mbps
:
: should do the job,, tha card still connect at lower speed depending on what it
: can with the selected AP
:
: in order to not jumping around you can try setting bssid _MAC_desired_AP_
:
: so long as your card is in monitor mode you may not connect nor get traffic at
: all

I don't mind jumping around (the rate selection stuff is there for a
reason), it's that I seemed to be stuck at 11Mbps. I've manually set it up
to 54Mbps, and still had good network connectivity.
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