5G roadblock: labor

Mon Dec 30 23:34:42 UTC 2019

On Mon, Dec 30, 2019 at 6:09 PM Michael Thomas <mike at mtcc.com> wrote:
>
>
> On 12/30/19 2:46 PM, Brandon Martin wrote:
> > On 12/30/19 5:42 PM, Michael Thomas wrote:
> >> Oh, I didn't know that. Seems like it's a relatively new thing. Seems
> >> like they went to a lot of trouble to essentially do what voip does.
> >> Or maybe not? I've been poking around trying figure out what's going
> >> on under the hood with wifi calling, and it seems like they're just
> >> tunneling PSTN bits over the internet. If true, that's certainly a
> >> quick and dirty hack. Maybe they're doing something similar for volte?
> >
> > My understanding is that VoLTE is signaled using SIP.  I don't know
> > how the media moves.  I think they tried to avoid re-inventing the
> > wheel. Most of the "phone" guys are slinging a lot of inter-network
> > calls via IP these days, anyway.
>
>
> Yeah, maybe it really is RTP because iirc, VoLTE can use different
> codecs. That would make some sense since a lot of those voice bits are
> going to end up as RTP at some point. I can understand the wifi hack
> since they may not have had the ability to directly deal with customer
> facing RTP from the phones 5 years ago.
>
> Maybe my google-foo is really bad, but it's not been easy to get an
> overview of what's going on under the hood for these. And I'd prefer to
> avoid the 3GPP tar pit.

I had thought the 'benefit' of LTE (specific to Voice) was a SIP UA
was implemented at the handset for all 'voice' over the LTE network.
(voice calls through your carrier - VoLTE)
  https://en.wikipedia.org/wiki/Voice_over_LTE

There are, or were when I last got told what's what... some problems
at the GRX with VoLTE when roaming... like: "The traffic appears as
handset data not handset calls" on the GRX.

For a long time in the start of the LTE network deployments handsets
just kept on using 3g (or less) for voice, because the radios existed,
the cell towers were equiped and 'VoLTE is scary still!"