ubuntu-phone team mailing list archive

["Marco A. Harrendorf" <marcokarlo@xxxxxx>]

-- 
Marco A. Harrendorf



Am Montag, den 20.07.2015, 14:15 +0300 schrieb Craig Harper:
> Hi Everyone
> 
> I would like to start a discussion on VoIP and Ubuntu Touch Phones.
> 

Let me put in my two cents:

* A native implementation of g722 and g729 would be great. If possible
in a way of a lib which can be implemented by other programs.
Furthermore, a reference implementation of this lib in a small VOIP
client would be nice.

* G722 is excellent and the de facto standard for VOIP telephony.
However, it is absolutely not usable if you are driving in your car and
are trying to phone over the UMTS connection.
In this scenario G729 is absolutely the best solution in regards to
quality and needed bandwidth.
The most VOIP provider which I used up to now only offer the both
codecs, so I would not put to many attention on other codecs.

* To my knowledge the G729 codec has quite high licensing costs of
roughly 6 Euros. For this reason, many Android VOIP clients offer to buy
this codec as an extra package.
In my opinion the best solution would be a similar way: G722 is shipped
by default and it is possible to use further codecs by the above
mentioned library if they bought and downloaded separately to a common
codec folder.

* In the long-term it would be nice if the library offers the possiblity
that the VOIP client based on the lib could be hooked into the dialer
and so on. Meaning that the VOIP number appears also in the dialer like
a third sim card, so that there is no visual different behaviour if I am
using the VOIP connection or the gsm connection.

* A big challenge in this regard could be the energy management in
regards to allow incoming VOIP calls since this requires a constant
background connection to the VOIP server.

> I have been in the VOIP industry for many many years, and there is always
> common problems with VoIP most of which can be other come one way or
> another.  But when it comes to mobile devices we have a few more thing to
> take into consideration and this can only be done from the Operating System
> rather than a applications.
> 
> So I would like to contribute some ideas and start a discussion about VoIPs
> future on the Ubuntu Touch platform.
> 
> 
> Quality
> 
> Today we have more and more bandwidth available so its not an issue its
> really a question of priority.  Just like when you make or receive a call,
> your GMS has priority over your speaker.  When you make or receive a VoIP
> call your call should have priority over your data, simple things can be
> done to allow this to happen through API to suspend other applications data
> for example downloads, there is no point in downloading updates when your
> on the phone call, or downloading emails.  This could be the greatest
> benefit.
> 
> Native VOIP over VOIP Application
> 
> I will say here, Native VOIP is always the way to go, it can have more
> integration with Operating System, it could be accessed by many
> applications and the benefits of things being open source the collective
> efforts can be focused on making the perfect VoIP experience, rather than
> lots of apps not quite making the mark, because they don't have the
> integration with the OS needed to provide quality.
> 
> Echo Cancellation
> 
> This is a must have to be build into any VoIP Client, Android also have a
> Native VoIP Client (Great Idea) but still today no Echo Cancellation even
> after so many years.  (I wonder if GSM companies have any influence over
> this)
> 
> NAT (Network Address Translation)
> 
> One of the biggest problems we have today and foreseeable future is Network
> Address Translation this has come along way over the years and VOIP
> networks have become better at handling the issues, but making sure the
> VOIP Client has STUN/ICE support will allow calls work in most network
> topologies.
> 
> Codec Support
> 
> This part i know this is a more of a complicated issue, as there is a world
> of difference licenses, there are now open source version, codecs are so
> important to help reduce quality issues, the smaller your packets the
> easier they are going to reach there destination uninterrupted.  Two of the
> most commonly used these days are g729 and g722, with g729 using a little
> as 9K and g722 using 14K but give providing wider bandwidth sound give us
> HD quality.
> 
> 
> Thanks for your time
> -- 
> Mailing list: https://launchpad.net/~ubuntu-phone
> Post to     : ubuntu-phone@xxxxxxxxxxxxxxxxxxx
> Unsubscribe : https://launchpad.net/~ubuntu-phone
> More help   : https://help.launchpad.net/ListHelp

Attachment: signature.asc
Description: This is a digitally signed message part