H.323 Vs SIP VoIP & Softphone Vs Hardphone

Archived from groups: comp.dcom.voice-over-ip (More info?)

Danilo Kempf Wrote:
> I would like to know that is there any difference in voice quality
> over-
> ADSL 256kbps connection while using H.323 or SIP , would like to know
> which is better for VOIP communication on low bandwidth,which give
> better compression , less echo and good quality .-
>
> Neither protocol has something to do with echo or voice quality. Both
> SIP
> and H.323 are signalling protocols which are used only to establish
> media
> channels. Those in turn are transmitted via RTP in both cases, so
> there
> shouldn't be a difference in quality between SIP or H.323 devices.
> -
> Also would like to know that is there a difference in voice quality
> and
> echo while using hardphone than a softphone . Which from both gives
> better sound quality and less echo on low bandwidth .-
>
> In theory there's no difference between a "hard"phone and a softphone.
> In
> practice most "tangible" VoIP phones include a real DSP doing some
> echo
> cancellation. With next to all Softphones echo cancellation is pretty
> uncommon, so you get better quality with a hardphone here.


What kind of hardware do i need to get good quality of voice , do i
need an IP phone or will the ATA be able to connect SIP provider . I
plan to use libretel.com to get a phone number which will ring on my
voip based phone I set up , so please suggest a good and reliable way
to setup .


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SIP2PSTN