[Asterisk-Users] Amazing, great protocol IAX

[Adam Hart]

Thomas Hutton wrote:

  > A) Which is better sound quality in this situation?
> On a local net (100 megabit) my SIP phone talks to Asterisk running on
> my firewall.  I only have 128K upload (sometimes) on my fricken
> Third-World DSL connection so I want to use GSM or ILBC going out over
> IAX2.  Should I let the DSP in the phone talk to asterisk in ULAW or
> ALAW, having Asterisk translate to GSM or should I force the phone to do
> it in the lower bandwidth codec?  I honestly can't tell a difference in
> quality or latency.  I'm not real impressed with the Grandstream
> Handytone 286 because it doesn't have GSM - so I'm stuck trying to
> compare straight through ILBC to translated GSM.  Any fine tuning codec
> advice would be appreciated.
> 

Why do you need GSM at all, just keep everything iLBC. Asterisk won't 
have to transcode and it will sound much better

-Adam