[Asterisk-Dev] 802.11b a contraindication?

[Chris Wilson]

Hi James,

> sip/rtp/ulaw over .11b on the other hand was a disaster.
> 
> (NB that it was the notebook on the 11b, not the local phone.
> Also, there was about 60 dBm more signal than the noise floor
> according to iwconfig, and rtt to the ap was 2.5 ms.)
> 
> I just switched to a lan (still w/ mtu 1200) and it works
> flawlessly.  Even calls to pstn via several iax2 gateways
> (including my pre-production service) were toll quality.
> 
> Has anyone else been seeing problems on 802.11 links?

Yes, we have. The call quality is not nearly as good as phone, or even 
mobile, due to frequent stuttering, probably caused by packet loss and/or 
jitter. Our customer complained enough that we are having to pull out the 
link and replace it with homebrew DSL over an alarm circuit (and I don't 
know if that will be better).

What sort of statistics do you get over long periods? High packet loss? 
(>1%) High jitter (>1ms)? Have you tried IAX2 with jitter buffer over the 
link, instead of SIP, and if so did it help? 

Cheers, Chris.
--
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