Yo Derek! Fancy meeting you here. I will look you up later.

Derek Atkins wrote:
> There's another problem. The wireless extensions have a size limit
> for the scan results data. The buffer size is a u16, which means you're
> limited to 65535 bytes. The network manager buffer increase algorithm
> keeps doubling the buffer size, so you get 2k, 4k, 8k, 16k, 32k, 64k..
> but 64k mod 2^16 == 0! Meaning you never actually get to try a full 64k
> buffer.
>
> A workaround to this issue is to change the NM code to max out at
> 65535 instead of 65536 or "100000" (which is the current limit)..
>
> This is being a MAJOR problem to a bunch of us at the IETF because
> we can easily hear well over 100 APs most of the time.
Please! We are use to seeing some of the worst-case work environments 
with too many APs and SSIDs for most code to cope with.
> Quoting Dan Williams <[EMAIL PROTECTED]>:
>
>> On Mon, 2008-03-10 at 23:40 -0400, Robert Moskowitz wrote:
>>> Ver 0.6.4 in Centos 5.1
>>>
>>> I am seeing 17 SSIDs in the current list. But I am not seeing one that
>>> I expected to see. And some of the listed SSIDs are 'stale'; that is
>>> they were visible in the part of the hotel I was in a couple minutes
>>> ago, but not in this part. So I guess a second question is how do you
>>> force a scan to produce a current SSID list?
>>
>> You don't force a scan. NetworkManager will periodically scan with a
>> backoff algorithm; it will start at 20 seconds and back off to 2
>> minutes. APs are kept in the scan list for a maximum of 6 minutes
>> before being culled.
>>
>> The problem is that wireless is hard, and sometimes cards/drivers miss
>> beacons. Often they will not report all the APs that are known to be
>> around at a given time. So NetworkManager takes a composite of the last
>> few scans as the scan list.
>>
>> 0.6.x also combines APs with the same SSID in the UI. 0.7 splits them
>> out at the NetworkManager layer, while the applet combines APs that are
>> similar based on more than just SSID (SSID, security settings, band,
>> channel).
>>
>>> Perhaps the question may be how many APs can be handled and then those
>>> are turned into the SSID list (when more than one AP per SSID is found
>>> as in the case of some of these SSIDs).
>>
>> Are any of the APs hidden?
>>
>
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