What vexes VoIP users?
nathan at atlasnetworks.us
Mon Feb 28 13:41:14 CST 2011
Odd - do the phones just randomly egress from different IPs in the pool if you don't? Is this perhaps a too-long registration interval issue? Short registration timers seem to deal with keeping the state table appeased on most firewalls. Any chance the NAT device has some god-forsaken ALG agent installed that's trying to proxy the SIP traffic?
(Yes, I hate ALGs. They are evil.)
> -----Original Message-----
> From: Owen DeLong [mailto:owen at delong.com]
> Sent: Monday, February 28, 2011 11:26 AM
> To: Bret Palsson
> Cc: nanog at nanog.org
> Subject: Re: What vexes VoIP users?
> Another vexation for VOIP in the SMB environment is that it rarely works
> particularly well (if at all) in light of a multiple-external-address NAT pool.
> You simply have to map all of your VOIP phones in such a way that they
> consistently get the same external IP every time or shit breaks badly.
> On Feb 28, 2011, at 11:11 AM, Bret Palsson wrote:
> > Since our company is a VoIP company, I will chime in to this topic.
> > Let's start off with the definitions so everyone is on the same page:
> > vex |veks|
> > verb [ trans. ]
> > make (someone) feel annoyed, frustrated, or worried, esp. with trivial
> > matters : the memory of the conversation still vexed him | [as adj. ]
> > ( vexing)the most vexing questions for policymakers.]
> > Alright, now that that's out of the way...
> > I am only referring to small medium business and some enterprise
> > (Those are all our customers, we do not do residential)
> > - Seemingly complex.
> > - Worried about the "What if the internet goes down" scenario.
> > - Call quality.
> > - Price
> > - Location
> > - Outages
> > Responses:
> > - Seemingly complex... Very true. Most VoIP companies, both hosted and
> on premises are difficult/time consuming to setup and make work they way
> you want it.
> > - What if the internet goes down. This one is a challenge. POTS actually
> have issues too, but when analog phone service goes down, there is no light
> on the phone indicating that the phones are not working so many customers
> perceive there is a problem. With the FCC mandating all POTS move to a VoIP
> backend (which for long hauls, is mostly already true) POTS will experience
> the same downtime as the internet.
> > However as we all know, the internet is built to tolerate outages.
> > For most people they don't understand how the internet actually works.
> > - Call quality... If a VoIP company pays for good bandwidth and maintains
> good relationships with peers, the only concern is the last-mile(From the CO
> to location). Now there is much more that plays in quality, ie. codec selection,
> voice buffer, locality to the pbx.
> > - Price... Believe it or not people are worried about paying less for better
> service. Who would have thought?
> > - Location... Location is super important both in the last mile and PBX.
> > - Last mile:
> > In older locations the copper in the ground is aged, if you
> can't get fiber and your stuck using T1, lines, then hopefully you are in a
> location that keeps the copper in the ground properly maintained. If you are
> in older locations, which one of our offices are, there are remedies, you can
> contact your bandwidth provider and have them do a head to head test using
> a BERD (bit error rate detector) and they can find the problem. But that's a
> whole other topic.
> > -PBX:
> > Some people believe that on premise is the best location for
> a PBX, this may or may not be true. I happen to believe that keeping it off
> premise is the way to go. You get up-time, redundancy, locality, and mobility.
> You just plug in your phone and your phone is up and running. Move offices..
> got bandwidth? Your good to go. No equipment to worry about, say a power
> outage happens, your voicemail still works people call in and are in call
> queues and have no clue you are down. Feels more like POTS with an
> enterprise backend.
> > -Outages: If the internet does fail, most providers offer WAN survivability.
> The customer plugs in phone lines into the router and if the internet goes
> down, they can make emergency calls or calls to the world limited by the
> number of lines the router can accept and are plugged in of course. Now in all
> our experience going on 7 years now, 90% of the time WAN outages happen,
> guess what also dies, the POTS! Who would have thought that when cables
> get cut, that the phone lines were also part of the cables?
> > There you go, some common worries, with some answers to hopefully
> sooth the vexed VoIP user.
> > Bret Palsson
> > Sr. Network & Systems Administrator
> > www.getjive.com
> > On Feb 28, 2011, at 11:37 AM, Valdis.Kletnieks at vt.edu wrote:
> >> On Mon, 28 Feb 2011 13:29:08 EST, Bret Clark said:
> >>> On 02/28/2011 01:17 PM, Leigh Porter wrote:
> >>>> VoIP at the last mile is just too niche at the moment. It's for people on
> this list, not my mother.
> >>> Baloney...if that was the case, then all these ILEC's wouldn't be
> >>> whining about POT's lines decreasing exponentially year over year!
> >> I do believe that the ILEC's are mostly losing POTS lines to cell
> >> phones, not to VoIP. I myself have a cell phone but no POTS service
> >> at my home address. On the other hand, I *am* seeing a metric ton of
> >> Vonage and Magic Jack ads on TV these days - if VoIP is "too niche", how
> are those two making any money?
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