Best codecs for cloud systems

[phonecheese]

Good Day,

We have a few offices in the US and a couple in Asia and Europe. We have on 3cx server that everyone is connected to- we have under 200 employees. What codecs do you all suggest to help combat latency and jitter for best phone quality?

Thanks

 

[N_G]

G711

 

[phonecheese]

OK thanks!

 

[N_G]

In v18 it will be configurable system wide. Apps will use g711 except when on lte or 4g in which case they use g729...

 

[leejor]

There are two "flavours" of G711 , a and u (also known as PCMA and PCMU on some devices). Each tends to be the "default" on devices in different parts of the world. Be sure you choose one of the two, system wide. G711 uses less processing power than some low bit-rate Codecs, which may make a difference on some devices, particularly older ones. It also has a much better chance of passing DTMF audio, if required.

If you want to get technical....

https://en.wikipedia.org/wiki/G.711

 

[phonecheese]

What about best codec for packet loss?

 

[leejor]

Unlike most other data flowing over the internet, lost voice packets cannot be re-send and re-assembled without affecting voice quality, as it is happening in relative "real time". So there is only going to be so much that can be done if the data connection fall below certain standards. Some Codecs may "push though" more audio in the same time frame, being a lower bit rate, but if a portion (usually multiple consecutive packets) never arrives, it is going to affect the audio, only so much can be buffered

Some reading.......

https://getvoip.com/blog/2018/12/20/acceptable-jitter-latency/

https://tomtalks.blog/2018/05/what-...d-round-trip-time-for-unified-communications/

 

[ChrisC_3CX]

Do bear in mind that, until the final release v18 comes along, if on v16 and you wish to have one codec used system wide, or at least for most situations/calls, and also wish to minimize transcoding, you will have to make sure you have made the appropriate changes in the following sections:

SIP Trunks --- SIP Trunks >> Edit
IP Phones --- Extensions >> Edit >> Phone Provisioning >> Select corresponding IP Phone
3CX Clients --- Extensions >> Edit >> Phone Provisioning >> Select 3CX App
3CX PBX --- Settings >> General

You can then re-evaluate the situation once v18 is officially released.