[CentOS] Centos 7: UPD packet checksum verification?

Wed Jan 29 13:16:12 UTC 2020
hw <hw at gc-24.de>

On Wednesday, January 29, 2020 12:38:32 AM CET Stephen John Smoogen wrote:
> On Tue, 28 Jan 2020 at 15:56, hw <hw at gc-24.de> wrote:
> > > For voice, that
> > > usually means a drop or other ugliness because it is assumed that if
> > > the quality is too bad, the people would just call each other again.
> > 
> > That's a funny idea.  Phone calls just worked fine and were good quality
> > 25
> > years ago, and mostly long before that.  I have never expected to have to
> > call anyone back because of poor quality in over 40 years, and I'm not
> > going to start to expect that now.
> 
> I got that from watching various training videos from the 1940's to
> the 1970's on phone switching systems... and also the basic design of
> how Erlang is programmed and deals with errors. It could be wrong,
> erroneous or crap. However talking to phone people over the years that
> was how they described things. A lot of them would say that a phone
> call could die a billion different ways and it was a miracle it didn't
> happen to everyone every day. It just happened to a couple of people a
> day in different places because everything was coded for redundancy
> and the expectation that it could get bad. That redundancy and
> over-engineering seems to have allowed for the 'worse case they will
> call back' to be a viable option.

Maybe it took a lot of effort to keep things working, I can't tell.  But I can 
tell that for over 40 years, there was one single interruption of the phone 
line when a major line was damaged due to construction work.  Calls weren't 
interrupted, either.

That changed with the introduction of mobile phones and got even worse with 
VOIP.  It only means that providers need to figure their stuff out.  It 
doesn't mean that less quality or less reliability would be acceptable --- 
especially not since we're paying over four times more for it than we used to.

> The problem is that if that was real or is still the case... unless
> your VOIP solution has as much redundancy.. failure is going to happen
> a lot more and in ways that lead to the general experience of the last
> 8 VOIP solutions I have been stuck with... dropped calls to Paypal as
> you said or sounding like a Dalek if the latency or such just got a
> little bad.

It's nonetheless not acceptable.  We are being forced to become increasingly 
dependent on what you might call the technology stack, and there isn't much 
left we could do without it because we don't have any other means and ways of 
doing things anymore.  That involves that the technology is increasingly to 
required to work better.