nanog mailing list archives

Re: What vexes VoIP users?


From: Jay Ashworth <jra () baylink com>
Date: Mon, 28 Feb 2011 19:24:30 -0500 (EST)

----- Original Message -----
From: "Joe Greco" <jgreco () ns sol net>

Yeah, um, well, hate to ruin that glorious illusion of the legacy
physical plant, but Ma Bell mostly doesn't run copper all the way
back to a real CO with a real battery room these days when they're
deploying new copper. So if you have a house built more than maybe
20 years ago, yeah, you're more likely to have a pair back to the CO,
but if you've ordered a second line, or you're in a new subdivision
and you're far from the CO, the chances you're actually on copper back
to the CO drops fairly quickly.

Ok, sure.  But probably to an RSU, which -- as I noted to Owen just now --
is engineered and monitored to quite a bit higher standards than I'm 
betting Comcast or FiOS is.

If you have DC continuity and good balance to ground on a copper pair,
you are *done*; no intermediate gear, no batteries, no config files,
nothing.

All I need at the residence is a 500 set, and the complexity of
*those* is super low, too.

Yes, it's elegant in a traditional way. I certainly agree. It has
some benefits. It also has some downsides in terms of usability,
things we wouldn't have noticed in 1970 but today we do. In an age
when cell phones can handle multiple calls and deliver Caller-ID
for a waiting call, it's nice to see feature parity on your landline.

Oh, I'm not arguing that.  

The question, for me, has always been "are we taking full account
of the *features* we get from traditionally engineered copper POTS" in
doing our cost benefit analysis to newer technologies...

and my answer was always "don' look like it to me."

The real, underlying problem is that people take insufficient notice
of all the complexity pinch points that they're engineering into
loops in exchange for the extra controllability they get because
everything's
digital end to end.

Looked at a different way, the "cold-war" reliability of the POTS network
maybe isn't quite as important as it once was. If you have a cell phone
and a VoIP line, maybe you're actually better off. If a plane crashes into
your local CO, perhaps you lose POTS and even your cell because the tower
was at the local CO. But if you've got a cell and a VoIP line that runs
over cable, maybe you actually have more diversity.

That's possible; there are *lots* of end-site use cases.

But that's end-user engineering; you could *always* improve your 
diversity if you were willing to put the time, though (and money)
into it.

And it doesn't *matter* whether it's riding on a cable internet link
the complexity of which is already amortized: you're now *adopting*
that
complexity onto the voice service... the semantics of which (used to
be) very well understood and not at all complex at all.

Yes, but you *gain* capabilities as well as losing some of the
benefits of the old system. We're gaining the ability to do things like texting
and transmitting pictures to 911 via the cellular network, for
example. Things change. Maybe some people do not need a cold-war relic of a
phone anymore.

"some people" is, for me, the important phrase in that sentence.

Cell phones have killed off pay phones and utility-grade watches;
I'm not sure we're the better for it in either case.

And SMS to 911 is still a *teeny* little capability; I think there's 
*one* whole PSAP in the US equipped for it so far.

From the user perception standpoint, I think, it's a tipping point
thing... just like Madison WI.

Cheers,
-- jr 'that was *not* an invitation' a

What, you want me to invite you for pizza in Madison? I hear there's
some good places near the Capitol...

"...to political arguments on NANOG".  Sorry not to show my work.  :-)

Cheers,
-- jra


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