[Asterisk-Users] super high bandwidth codec

[Andrew C. Brown]

Brian Capouch wrote:
> Geoff Manning wrote:
> 
>>>>> Skype uses wideband-ilbc.
>>>>>
>>>>
>>
>> I don't think thats right. I think it just uses iLBC over it's own
>> proprietary Voip protocol.
>> http://www.skype.com/help/faq/technical.html
>> How much bandwidth does Skype use while I'm in a call?
>>     Skype automatically selects the best codec depending on the
>> connection
>> between yourself and the person you are calling. On average, Skype uses
>> between 3-16 kilobytes/sec depending on bandwidth available for other
>> party,
>> network conditions in between, callers CPU performance, etc.
> 
> 
> I don't think that's correct.
> 
> I don't have the link to the Columbia paper where they tried (with only
> mixed success) to figure out what all nefarious stuff Skype does
> (hijacking port 80 being the most pernicious) but I'm pretty sure they
> have figured out that if possible, it will use the (proprietary)
> wideband version of iLBC.

BTW, with all this talk about "wideband iLBC", we should probably start
using correct terms since iLBC actually stands for "internet Low
Bandwidth Codec". So "wb iLBC" is an oxymoron. GIPS has a few
proprietary codecs. Probably the one we are referring to is "iPCM-wb",
which according to GIPS (globalipsound.com) "...is a wide band codec
with extreme robustness against packet loss [that] provides
better-than-PSTN quality across ... the public Internet." They also have
iSAC which supposedly "...makes VoIP communications possible using a
dial-up modem, automatically adjusting transmission rates to deliver
better-than-PSTN voice quality."

Skype is listed as a customer of GIPS on GIPS' website, but I don't know
which codec Skype uses. It must be one of the proprietary ones though.