Re: [VoiceOps] Call term misrouting?

[Nathan Anderson via VoiceOps]

Mike Johnston wrote:

> On 2023-07-26 17:43, Paul Timmins via VoiceOps wrote:
> > I wouldn't be surprised to see carriers dumping these calls via a GSM 
> > gateway, this is really common in europe with gray routes. It'd 
> > explain why you get weird cellular voicemail, if they sent the number 
> > to the cell phone wrong to actually dial out.
> 
> I've heard of this!
> In one instance, the call would come through every one in a dozen or so 
> attempts.  And it would often have the wrong calling number.  Generally 
> belonging to a cell provider.  Audio was not great and there was 
> noticeable latency.  The call would only go for a few minutes before 
> dropping.

Going back to the "wrong voicemail system" thing, though...I could easily see a 
call being placed via a GSM gateway carrying the wrong CLID info (call being 
sourced from phone # owned by the cell carrier, rather than the original 
caller).  But whenever we would hit these voicemail systems, they would clearly 
read back to me the number that I *dialed* (e.g., "2125551212 is not 
available"), demonstrating that -- IF this is a legit voicemail system -- the 
diversion/RDNIS info is being properly signalled to it.

Having RDNIS pass through unmolested over wireless via a gateway seems 1) 
unlikely (how would that even work? is it possible for a wireless endpoint to 
signal that??), and 2) the sensation one gets is that the mobile carrier's OWN 
voicemail system has somehow mistakenly been sent the call, which still doesn't 
make sense.

So your theory about it being a fake termination makes way more sense to me.

-- Nathan

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Re: [VoiceOps] Call term misrouting?

[Mike Johnston via VoiceOps]

On 2023-07-26 17:43, Paul Timmins via VoiceOps wrote:

I wouldn't be surprised to see carriers dumping these calls via a GSM gateway, 
this is really common in europe with gray routes. It'd explain why you get 
weird cellular voicemail, if they sent the number to the cell phone wrong to 
actually dial out.


I've heard of this!
In one instance, the call would come through every one in a dozen or so 
attempts.  And it would often have the wrong calling number.  Generally 
belonging to a cell provider.  Audio was not great and there was 
noticeable latency.  The call would only go for a few minutes before 
dropping.


I have on a couple occasions had the opportunity to have both phones 
sitting side-by-side.  A phone from a telco with "unlimited" shady long 
distance, and a phone from my telco.  I kept detailed logs of each call, 
with audio recordings of the fake voicemails, fake person talking 
through static, and so on.  They only have so many fake recordings, so 
they eventually repeat themselves.  We packaged up the logs and the 
audio files and sent it all to our PUC.  Got fixed real fast.  But just 
for that one company.

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Re: [VoiceOps] Call term misrouting?

[Nathan Anderson via VoiceOps]

I suppose a GSM gateway is a remote possibility.  But I don't see how that 
explains the voicemail system answering the call.  If I place a call from my 
personal cell to some number, and for some reason my cell carrier fails to 
complete that call for me, that call is not then sent to my cell carrier's *own 
voicemail system*.  Something would have to be really screwed up for that to 
happen.

-- Nathan

-Original Message-
From: Paul Timmins [mailto:ptimm...@clearrate.com] 
Sent: Wednesday, July 26, 2023 3:44 PM
To: Nathan Anderson
Cc: voiceops@voiceops.org
Subject: Re: [VoiceOps] Call term misrouting?

I wouldn't be surprised to see carriers dumping these calls via a GSM gateway, 
this is really common in europe with gray routes. It'd explain why you get 
weird cellular voicemail, if they sent the number to the cell phone wrong to 
actually dial out.

> On Jul 26, 2023, at 6:36 PM, Nathan Anderson via VoiceOps 
>  wrote:
> 
> I just want to briefly point out that I was engaging in some hyperbolic 
> metaphor with the "twelve rounds" bit, and it seems to have misfired.  It 
> wasn't literally 12, and apologies for (unintentionally) misleading anyone.  
> I was attempting (poorly, apparently) to use a boxing analogy (and what I 
> thought was a fairly commonly-understood idiom) merely to underline that the 
> fight was long and drawn out & it took a lot of back and forth.  It also 
> involved 2 separate tickets with 2 of my direct providers, one a few months 
> back, and the latest one was opened last Thursday and was only resolved 
> yesterday after number of exchanges (that I didn't bother to actually count; 
> heh) over the course of that near-week-long period.  And now it's looking 
> like we are going to need to open yet another ticket with a 3rd provider of 
> ours...
> 
> I was also more interested in exactly what is happening during the "routing 
> via circuitous pathways" that would cause a call to be delivered to the wrong 
> destination.  I can understand crap call quality, long connection times, etc. 
> all in an effort to save a buck.  But sending the call to the wrong endpoint 
> entirely??  Assuming it isn't someone doing something intentionally 
> fraudulent, what *technical* explanation can there be for such a break-down 
> occurring?
> 
> -- Nathan
> 
> -Original Message-
> From: David Frankel [mailto:dfran...@zipdx.com] 
> Sent: Wednesday, July 26, 2023 8:01 AM
> To: 'Mark R Lindsey'; Nathan Anderson
> Cc: voiceops@voiceops.org
> Subject: RE: [VoiceOps] Call term misrouting?
> 
> Mark's reference to the RCC regs is pointing in the right direction.
> 
> The problem stems from sketchy providers trying to save money routing via
> circuitous pathways, which often end up with the misbehaviors cited in this
> thread.
> 
> Nathan's comments that he's been through TWELVE rounds of provider
> blacklisting shows what a mess this is.
> 
> Recognizing the problem, the FCC as part of their RCC initiative several
> years ago put a "safe harbor" in place to incent providers to perform direct
> routing to rural locations:
> https://www.ecfr.gov/current/title-47/chapter-I/subchapter-B/part-64/subpart
> -V/section-64.2107
> 
> Go to a reputable intermediate provider and tell them that you want a rate
> deck that conforms to this safe harbor, which dictates direct or one-hop
> routing. You will pay incrementally more for this rate deck, and you will
> get more than your money back in terms of time saved from all this trauma
> chasing completion issues. If you want a suggestion of where to start, I'd
> say try Inteliquent.
> 
> 
> David Frankel
> ZipDXR LLC
> St. George, UT USA
> 
> -Original Message-
> From: VoiceOps  On Behalf Of Mark R Lindsey
> via VoiceOps
> Sent: Wednesday, July 26, 2023 8:32 AM
> To: Nathan Anderson 
> Cc: voiceops@voiceops.org
> Subject: Re: [VoiceOps] Call term misrouting?
> 
> It would not only be a form of fraud, but sounds be a violation of the Rural
> Call Completion rules (specifically 47 CFR 64.2119(a)). I would recommend
> you make a complaint to the FCC and categorize them at Rural Call Completion
> issues. Provide as much info as you can on carrier names, dates and times of
> the calls.
> 
> The FCC staff do contact carriers and intermediate providers to track down
> RCC problems. I worked with one rural provider in the US on an issue related
> to rural call completion, and our complaints were getting callbacks to help
> us troubleshoot from Comcast, Verizon and AT&T at different points in the
> troubleshooting.
> 
> The FCC requires all the intermediate providers to retain records of call
> routing a

Re: [VoiceOps] Call term misrouting?

[Nathan Anderson via VoiceOps]

Mike Johnston wrote:

> I serve a rural area.  I do the technical "make it work" stuff.  I'm 
> generally only involved in the business dealings insofar as determining 
> technical incompatibilities (draw 7 red lines, all perpendicular, some 
> with green ink and some with transparent).  That said, please forgive 
> any errors in what I say, and feel free to correct me.

This was all super interesting and helpful; thanks!

> I try to find numbers that go to IVRs, fax numbers, automated airport 
> weather numbers, etc.  Anything that doesn't involve bothering a human 
> over and over.  It has to be with the same OCN though, and generally 
> needs to be in the same NPA-NXX too.

Yes; correct.  In this particular instance, a county library system that we 
service a lot of branches for was having trouble calling a particular branch 
that lies outside of our service area.  I knew that branch's operating hours, 
and they have an answering machine, so I would run my tests while they were 
closed.

> These are generally fake voicemails.  Just a recording of some voicemail 
> intro, to make you think you hit a voicemail box.  The call hasn't 
> actually been mis-routed.  It hasn't been "routed" anywhere, other than 
> to an audio file.

I suspected it was either this, or it was hitting a genuine voicemail system 
that was perhaps misconfigured and accepting calls for any RDNIS / voicemail 
boxes it received.  Though I guess if I'd thought about it for 2 seconds, if it 
had actually been AT&T's voicemail system, then it would have told me that the 
destination mailbox in question had not yet been initialized / set up.

> Are you sure it actually rang a line at some business?  Or maybe it was, 
> again, just an audio file?  Some wav file on a server at Bob's Shady 
> Long Distance Shack?

[...]

> I would argue it is fraud.  But again, prove to me they are actually 
> "routing" to any number, and not some audio file.

Fair point.  I don't actually know.

-- Nathan

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Re: [VoiceOps] Call term misrouting?

[Paul Timmins via VoiceOps]

I wouldn't be surprised to see carriers dumping these calls via a GSM gateway, 
this is really common in europe with gray routes. It'd explain why you get 
weird cellular voicemail, if they sent the number to the cell phone wrong to 
actually dial out.

> On Jul 26, 2023, at 6:36 PM, Nathan Anderson via VoiceOps 
>  wrote:
> 
> I just want to briefly point out that I was engaging in some hyperbolic 
> metaphor with the "twelve rounds" bit, and it seems to have misfired.  It 
> wasn't literally 12, and apologies for (unintentionally) misleading anyone.  
> I was attempting (poorly, apparently) to use a boxing analogy (and what I 
> thought was a fairly commonly-understood idiom) merely to underline that the 
> fight was long and drawn out & it took a lot of back and forth.  It also 
> involved 2 separate tickets with 2 of my direct providers, one a few months 
> back, and the latest one was opened last Thursday and was only resolved 
> yesterday after number of exchanges (that I didn't bother to actually count; 
> heh) over the course of that near-week-long period.  And now it's looking 
> like we are going to need to open yet another ticket with a 3rd provider of 
> ours...
> 
> I was also more interested in exactly what is happening during the "routing 
> via circuitous pathways" that would cause a call to be delivered to the wrong 
> destination.  I can understand crap call quality, long connection times, etc. 
> all in an effort to save a buck.  But sending the call to the wrong endpoint 
> entirely??  Assuming it isn't someone doing something intentionally 
> fraudulent, what *technical* explanation can there be for such a break-down 
> occurring?
> 
> -- Nathan
> 
> -Original Message-
> From: David Frankel [mailto:dfran...@zipdx.com] 
> Sent: Wednesday, July 26, 2023 8:01 AM
> To: 'Mark R Lindsey'; Nathan Anderson
> Cc: voiceops@voiceops.org
> Subject: RE: [VoiceOps] Call term misrouting?
> 
> Mark's reference to the RCC regs is pointing in the right direction.
> 
> The problem stems from sketchy providers trying to save money routing via
> circuitous pathways, which often end up with the misbehaviors cited in this
> thread.
> 
> Nathan's comments that he's been through TWELVE rounds of provider
> blacklisting shows what a mess this is.
> 
> Recognizing the problem, the FCC as part of their RCC initiative several
> years ago put a "safe harbor" in place to incent providers to perform direct
> routing to rural locations:
> https://www.ecfr.gov/current/title-47/chapter-I/subchapter-B/part-64/subpart
> -V/section-64.2107
> 
> Go to a reputable intermediate provider and tell them that you want a rate
> deck that conforms to this safe harbor, which dictates direct or one-hop
> routing. You will pay incrementally more for this rate deck, and you will
> get more than your money back in terms of time saved from all this trauma
> chasing completion issues. If you want a suggestion of where to start, I'd
> say try Inteliquent.
> 
> 
> David Frankel
> ZipDXR LLC
> St. George, UT USA
> 
> -Original Message-
> From: VoiceOps  On Behalf Of Mark R Lindsey
> via VoiceOps
> Sent: Wednesday, July 26, 2023 8:32 AM
> To: Nathan Anderson 
> Cc: voiceops@voiceops.org
> Subject: Re: [VoiceOps] Call term misrouting?
> 
> It would not only be a form of fraud, but sounds be a violation of the Rural
> Call Completion rules (specifically 47 CFR 64.2119(a)). I would recommend
> you make a complaint to the FCC and categorize them at Rural Call Completion
> issues. Provide as much info as you can on carrier names, dates and times of
> the calls.
> 
> The FCC staff do contact carriers and intermediate providers to track down
> RCC problems. I worked with one rural provider in the US on an issue related
> to rural call completion, and our complaints were getting callbacks to help
> us troubleshoot from Comcast, Verizon and AT&T at different points in the
> troubleshooting.
> 
> The FCC requires all the intermediate providers to retain records of call
> routing attempts in a readily-accessed format for six months.
> https://www.ecfr.gov/current/title-47/section-64.2103
> 
> There are minimum standards of quality for carriers related to the
> successful delivery and routing of calls.
> https://www.ecfr.gov/current/title-47/section-64.2119
> 
> 
> (I'm an engineer, not a lawyer, and this is technical advice, not legal
> advice.) Mark R Lindsey | +1-229-316-0013 | m...@ecg.co | Schedule a Meeting
> <https://ecg.co/lindsey/schedule> | Newsletter
> <https://www.linkedin.com/newsletters/mark-lindsey-voice-7021614437413330944
> />
>

Re: [VoiceOps] Call term misrouting?

[Nathan Anderson via VoiceOps]

I just want to briefly point out that I was engaging in some hyperbolic 
metaphor with the "twelve rounds" bit, and it seems to have misfired.  It 
wasn't literally 12, and apologies for (unintentionally) misleading anyone.  I 
was attempting (poorly, apparently) to use a boxing analogy (and what I thought 
was a fairly commonly-understood idiom) merely to underline that the fight was 
long and drawn out & it took a lot of back and forth.  It also involved 2 
separate tickets with 2 of my direct providers, one a few months back, and the 
latest one was opened last Thursday and was only resolved yesterday after 
number of exchanges (that I didn't bother to actually count; heh) over the 
course of that near-week-long period.  And now it's looking like we are going 
to need to open yet another ticket with a 3rd provider of ours...

I was also more interested in exactly what is happening during the "routing via 
circuitous pathways" that would cause a call to be delivered to the wrong 
destination.  I can understand crap call quality, long connection times, etc. 
all in an effort to save a buck.  But sending the call to the wrong endpoint 
entirely??  Assuming it isn't someone doing something intentionally fraudulent, 
what *technical* explanation can there be for such a break-down occurring?

-- Nathan

-Original Message-
From: David Frankel [mailto:dfran...@zipdx.com] 
Sent: Wednesday, July 26, 2023 8:01 AM
To: 'Mark R Lindsey'; Nathan Anderson
Cc: voiceops@voiceops.org
Subject: RE: [VoiceOps] Call term misrouting?

Mark's reference to the RCC regs is pointing in the right direction.

The problem stems from sketchy providers trying to save money routing via
circuitous pathways, which often end up with the misbehaviors cited in this
thread.

Nathan's comments that he's been through TWELVE rounds of provider
blacklisting shows what a mess this is.

Recognizing the problem, the FCC as part of their RCC initiative several
years ago put a "safe harbor" in place to incent providers to perform direct
routing to rural locations:
https://www.ecfr.gov/current/title-47/chapter-I/subchapter-B/part-64/subpart
-V/section-64.2107

Go to a reputable intermediate provider and tell them that you want a rate
deck that conforms to this safe harbor, which dictates direct or one-hop
routing. You will pay incrementally more for this rate deck, and you will
get more than your money back in terms of time saved from all this trauma
chasing completion issues. If you want a suggestion of where to start, I'd
say try Inteliquent.


David Frankel
ZipDXR LLC
St. George, UT USA

-Original Message-
From: VoiceOps  On Behalf Of Mark R Lindsey
via VoiceOps
Sent: Wednesday, July 26, 2023 8:32 AM
To: Nathan Anderson 
Cc: voiceops@voiceops.org
Subject: Re: [VoiceOps] Call term misrouting?

It would not only be a form of fraud, but sounds be a violation of the Rural
Call Completion rules (specifically 47 CFR 64.2119(a)). I would recommend
you make a complaint to the FCC and categorize them at Rural Call Completion
issues. Provide as much info as you can on carrier names, dates and times of
the calls.

The FCC staff do contact carriers and intermediate providers to track down
RCC problems. I worked with one rural provider in the US on an issue related
to rural call completion, and our complaints were getting callbacks to help
us troubleshoot from Comcast, Verizon and AT&T at different points in the
troubleshooting.

The FCC requires all the intermediate providers to retain records of call
routing attempts in a readily-accessed format for six months.
https://www.ecfr.gov/current/title-47/section-64.2103

There are minimum standards of quality for carriers related to the
successful delivery and routing of calls.
https://www.ecfr.gov/current/title-47/section-64.2119


(I'm an engineer, not a lawyer, and this is technical advice, not legal
advice.) Mark R Lindsey | +1-229-316-0013 | m...@ecg.co | Schedule a Meeting
<https://ecg.co/lindsey/schedule> | Newsletter
<https://www.linkedin.com/newsletters/mark-lindsey-voice-7021614437413330944
/>


> On Jul 26, 2023, at 09:28, Nathan Anderson via VoiceOps
 wrote:
> 
> ...by which I mean, we send a call to a term provider via SIP, who then
*seems* to terminate the call to the wrong callee entirely.
> 
> What the heck actually causes this?
> 
> Whenever I have experienced it, it inevitably involves a rural carrier of
some kind, one that likely charges a lot to accept traffic.  Over the course
of a few days, we just went through twelve rounds of having a wholesale term
provider blacklist various carriers from their LCRs for calls headed to this
particular exchange, before the problem stopped happening.  "Is it working
yet?"  "Nope."  "How about now?"  "Still nope."  And it's random and
sporadic enough that I have to place a

Re: [VoiceOps] Call term misrouting?

[Mike Johnston via VoiceOps]

I serve a rural area.  I do the technical "make it work" stuff.  I'm 
generally only involved in the business dealings insofar as determining 
technical incompatibilities (draw 7 red lines, all perpendicular, some 
with green ink and some with transparent).  That said, please forgive 
any errors in what I say, and feel free to correct me.


On 2023-07-26 08:28, Nathan Anderson via VoiceOps wrote:

...by which I mean, we send a call to a term provider via SIP, who then *seems* 
to terminate the call to the wrong callee entirely.

What the heck actually causes this?


A long distance carrier, generally an intermediate one, being shady. 
Here at my workplace, we call that carrier something like, "Bob's Shady 
Long Distance Shack."  Bob probably charges 1 cent per minutes, or less, 
as a flat rate.  When he gets calls for cellphones or urban areas, the 
calls might cost him 0.1 of a cent per minute, and Bob is doing good. 
But when Bob gets calls to rural areas that cost more than one 1 cent 
per minute, he doesn't like that.  It cuts into his profits.  So he does 
shady stuff.



Whenever I have experienced it, it inevitably involves a rural carrier of some 
kind, one that likely charges a lot to accept traffic.


"Charges a lot to accept traffic," makes it seem like a troll under a 
bridge, making up whatever rate they want to pass.  My understanding is 
that these rates were set by a process that involved distance, to help 
cover fixed infrastructure costs.  Thus, rural areas cost more to call.



Over the course of a few days, we just went through twelve rounds of having a 
wholesale term provider blacklist various carriers from their LCRs for calls 
headed to this particular exchange, before the problem stopped happening.


It seems that Bob's Shady Long Distance Shack is popular.  Either that, 
or there are multiple intermediate carriers in play.  For example, if 
you route a call to carrier A, they route the call to carrier I, who 
routes the call to carrier BOB.  If you try a different carrier, they 
might also send the call to carrier I, who will still send the call to 
carrier BOB.



"Is it working yet?"  "Nope."  "How about now?"  "Still nope."  And it's random 
and sporadic enough that I have to place a lot of test calls (as well as continue to field feedback from our end-users) 
before I can be sure that the problem is actually fixed.  It's aggravating...


I try to find numbers that go to IVRs, fax numbers, automated airport 
weather numbers, etc.  Anything that doesn't involve bothering a human 
over and over.  It has to be with the same OCN though, and generally 
needs to be in the same NPA-NXX too.


We have a test number with an announcement in every one of our assigned 
blocks.  It is the last number, such as  or 2999.  If you want to 
test, look up OCN 1505 and OCN 194F.  If you would like an exhaustive 
list of those numbers, email me off list.



It doesn't seem to be the final destination carrier that's screwing up the call routing 
after having received the call: I can call the same number over and over again through a 
"reputable" carrier, or via my personal cell (but I repeat myself), and get 
connected to the right destination every time.  Based on my experiences, I highly doubt 
the misdirected calls are even getting as far as the CO's switch for that exchange.


Correct.  If I had received the call, I would have routed the call.  I 
can't imagine why any rural telephone company would route calls to fake 
voicemails, fake announcements, static noises, etc.


I've even worked with my upstream on some calls, and they don't receive 
them either.  If they received the call, they would have sent it to me.



So I have to hypothesize that some sketch carrier getting is picked from an LCR 
table, one who just doesn't like sending the call to a rural carrier who either 
charges that much


The FCC has a page about this, by the way.

https://www.fcc.gov/general/rural-call-completion-problems-long-distance-or-wireless-calling-rural-areas

When working with your carriers, using the exact phrase "Rural Call 
Completion" should help.  And please, file reports with the FCC!  There 
isn't much the rural telephone companies can do at the receiving end, 
since we don't know about the calls we don't receive.



or that they suspect is engaging in fraud.


It's possible you are referring to this:
https://en.wikipedia.org/wiki/Traffic_pumping
Is that a thing that some rural telcos are still doing?


But...WHY *misroute* it?  I'd rather you just reject the call if you don't want 
to carry it.


I also want to know!  Don't offer to route calls you can't complete, right?


The misrouted calls in this latest case more often than not seemed to be hitting a 
foreign voicemail system that sounded an awful lot like AT&T Mobility's default 
voicemail greeting.


These are generally fake voicemails.  Just a recording of some voicemail 
intro, to make you think you hit a voicemail box.  The call hasn't 
actu

Re: [VoiceOps] Call term misrouting?

[David Frankel via VoiceOps]

Mark's reference to the RCC regs is pointing in the right direction.

The problem stems from sketchy providers trying to save money routing via
circuitous pathways, which often end up with the misbehaviors cited in this
thread.

Nathan's comments that he's been through TWELVE rounds of provider
blacklisting shows what a mess this is.

Recognizing the problem, the FCC as part of their RCC initiative several
years ago put a "safe harbor" in place to incent providers to perform direct
routing to rural locations:
https://www.ecfr.gov/current/title-47/chapter-I/subchapter-B/part-64/subpart
-V/section-64.2107

Go to a reputable intermediate provider and tell them that you want a rate
deck that conforms to this safe harbor, which dictates direct or one-hop
routing. You will pay incrementally more for this rate deck, and you will
get more than your money back in terms of time saved from all this trauma
chasing completion issues. If you want a suggestion of where to start, I'd
say try Inteliquent.


David Frankel
ZipDXR LLC
St. George, UT USA

-Original Message-
From: VoiceOps  On Behalf Of Mark R Lindsey
via VoiceOps
Sent: Wednesday, July 26, 2023 8:32 AM
To: Nathan Anderson 
Cc: voiceops@voiceops.org
Subject: Re: [VoiceOps] Call term misrouting?

It would not only be a form of fraud, but sounds be a violation of the Rural
Call Completion rules (specifically 47 CFR 64.2119(a)). I would recommend
you make a complaint to the FCC and categorize them at Rural Call Completion
issues. Provide as much info as you can on carrier names, dates and times of
the calls.

The FCC staff do contact carriers and intermediate providers to track down
RCC problems. I worked with one rural provider in the US on an issue related
to rural call completion, and our complaints were getting callbacks to help
us troubleshoot from Comcast, Verizon and AT&T at different points in the
troubleshooting.

The FCC requires all the intermediate providers to retain records of call
routing attempts in a readily-accessed format for six months.
https://www.ecfr.gov/current/title-47/section-64.2103

There are minimum standards of quality for carriers related to the
successful delivery and routing of calls.
https://www.ecfr.gov/current/title-47/section-64.2119


(I'm an engineer, not a lawyer, and this is technical advice, not legal
advice.) Mark R Lindsey | +1-229-316-0013 | m...@ecg.co | Schedule a Meeting
<https://ecg.co/lindsey/schedule> | Newsletter
<https://www.linkedin.com/newsletters/mark-lindsey-voice-7021614437413330944
/>


> On Jul 26, 2023, at 09:28, Nathan Anderson via VoiceOps
 wrote:
> 
> ...by which I mean, we send a call to a term provider via SIP, who then
*seems* to terminate the call to the wrong callee entirely.
> 
> What the heck actually causes this?
> 
> Whenever I have experienced it, it inevitably involves a rural carrier of
some kind, one that likely charges a lot to accept traffic.  Over the course
of a few days, we just went through twelve rounds of having a wholesale term
provider blacklist various carriers from their LCRs for calls headed to this
particular exchange, before the problem stopped happening.  "Is it working
yet?"  "Nope."  "How about now?"  "Still nope."  And it's random and
sporadic enough that I have to place a lot of test calls (as well as
continue to field feedback from our end-users) before I can be sure that the
problem is actually fixed.  It's aggravating...
> 
> It doesn't seem to be the final destination carrier that's screwing up the
call routing after having received the call: I can call the same number over
and over again through a "reputable" carrier, or via my personal cell (but I
repeat myself), and get connected to the right destination every time.
Based on my experiences, I highly doubt the misdirected calls are even
getting as far as the CO's switch for that exchange.
> 
> So I have to hypothesize that some sketch carrier getting is picked from
an LCR table, one who just doesn't like sending the call to a rural carrier
who either charges that much, or that they suspect is engaging in fraud.
But...WHY *misroute* it?  I'd rather you just reject the call if you don't
want to carry it.
> 
> The misrouted calls in this latest case more often than not seemed to 
> be hitting a foreign voicemail system that sounded an awful lot like 
> AT&T Mobility's default voicemail greeting.  But we have definitely 
> had calls just end up ringing the absolute wrong phone...in one case a 
> few months back, I tried ringing the public library branch in this one 
> rural town, and ended up getting the answering machine for some random 
> business (...and also the call quality was *abysmal* on top of that).  
> (Never did manage to figure out where that business whose answering 
> machine I go

Re: [VoiceOps] Call term misrouting?

[Mark R Lindsey via VoiceOps]

It would not only be a form of fraud, but sounds be a violation of the Rural 
Call Completion rules (specifically 47 CFR 64.2119(a)). I would recommend you 
make a complaint to the FCC and categorize them at Rural Call Completion 
issues. Provide as much info as you can on carrier names, dates and times of 
the calls.

The FCC staff do contact carriers and intermediate providers to track down RCC 
problems. I worked with one rural provider in the US on an issue related to 
rural call completion, and our complaints were getting callbacks to help us 
troubleshoot from Comcast, Verizon and AT&T at different points in the 
troubleshooting.

The FCC requires all the intermediate providers to retain records of call 
routing attempts in a readily-accessed format for six months.
https://www.ecfr.gov/current/title-47/section-64.2103

There are minimum standards of quality for carriers related to the successful 
delivery and routing of calls.
https://www.ecfr.gov/current/title-47/section-64.2119


(I'm an engineer, not a lawyer, and this is technical advice, not legal advice.)
Mark R Lindsey | +1-229-316-0013 | m...@ecg.co | Schedule a Meeting 
 | Newsletter 



> On Jul 26, 2023, at 09:28, Nathan Anderson via VoiceOps 
>  wrote:
> 
> ...by which I mean, we send a call to a term provider via SIP, who then 
> *seems* to terminate the call to the wrong callee entirely.
> 
> What the heck actually causes this?
> 
> Whenever I have experienced it, it inevitably involves a rural carrier of 
> some kind, one that likely charges a lot to accept traffic.  Over the course 
> of a few days, we just went through twelve rounds of having a wholesale term 
> provider blacklist various carriers from their LCRs for calls headed to this 
> particular exchange, before the problem stopped happening.  "Is it working 
> yet?"  "Nope."  "How about now?"  "Still nope."  And it's random and sporadic 
> enough that I have to place a lot of test calls (as well as continue to field 
> feedback from our end-users) before I can be sure that the problem is 
> actually fixed.  It's aggravating...
> 
> It doesn't seem to be the final destination carrier that's screwing up the 
> call routing after having received the call: I can call the same number over 
> and over again through a "reputable" carrier, or via my personal cell (but I 
> repeat myself), and get connected to the right destination every time.  Based 
> on my experiences, I highly doubt the misdirected calls are even getting as 
> far as the CO's switch for that exchange.
> 
> So I have to hypothesize that some sketch carrier getting is picked from an 
> LCR table, one who just doesn't like sending the call to a rural carrier who 
> either charges that much, or that they suspect is engaging in fraud.  
> But...WHY *misroute* it?  I'd rather you just reject the call if you don't 
> want to carry it.
> 
> The misrouted calls in this latest case more often than not seemed to be 
> hitting a foreign voicemail system that sounded an awful lot like AT&T 
> Mobility's default voicemail greeting.  But we have definitely had calls just 
> end up ringing the absolute wrong phone...in one case a few months back, I 
> tried ringing the public library branch in this one rural town, and ended up 
> getting the answering machine for some random business (...and also the call 
> quality was *abysmal* on top of that).  (Never did manage to figure out where 
> that business whose answering machine I got was actually located.  It was a 
> generic-enough name for a business in their industry, but what I can tell you 
> is that there was no business by that name in the rate centers covered by 
> that rural carrier.  And also that my CDRs back up the fact that I did *not* 
> mis-dial that call.)
> 
> About the only theory I can come up with that makes a lick of sense is that 
> these cut-rate carriers in these LCRs decide to throw to a rando number if 
> they get asked to term to a high-cost exchange, so that they can record a 
> call completion and charge the caller for it anyway.  Which would be a form 
> of fraud itself, if that's actually happening.
> 
> I suppose there could be a leg of the call that is being signalled 
> non-digitally (so, not SS7, not SIP, ...), and something is getting either 
> mis-transmitted or mis-interpreted.  But if they were doing something like 
> (e.g.) in-band DTMF over a crap connection to an old switch somewhere, I 
> would expect dropped digits, and thus not enough to construct a viable & 
> valid destination number out of.
> 
> -- Nathan
> 
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Re: [VoiceOps] Call term misrouting?

[David Knell via VoiceOps]

Hi Nathan -

I don't think that your supposition that the calls are being misrouted for
the carrier doing it to collect the termination revenue's far from the
truth.  This has been going on forever in myriad ways - send answer on
ringing (extends the chargeable duration of a call), route calls to fake
voicemail systems (had this just the other day on a UK cell route), answer
calls with a recording of a "fruity" conversation (so the caller assumes
it's a crossed line and eavesdrops), etc., etc., etc.  We've had calls to
our IVR services hijacked and terminated on a clone of the service.  It's
just nuts.

The root of the problem, in your case, is rural carriers who have a dozen
subscribers and a massive free conference call service hanging off an
enormous termination rate..

Cheers --

Dave

On Wed, Jul 26, 2023 at 3:28 PM Nathan Anderson via VoiceOps <
voiceops@voiceops.org> wrote:

> ...by which I mean, we send a call to a term provider via SIP, who then
> *seems* to terminate the call to the wrong callee entirely.
>
> What the heck actually causes this?
>
> Whenever I have experienced it, it inevitably involves a rural carrier of
> some kind, one that likely charges a lot to accept traffic.  Over the
> course of a few days, we just went through twelve rounds of having a
> wholesale term provider blacklist various carriers from their LCRs for
> calls headed to this particular exchange, before the problem stopped
> happening.  "Is it working yet?"  "Nope."  "How about now?"  "Still nope."
> And it's random and sporadic enough that I have to place a lot of test
> calls (as well as continue to field feedback from our end-users) before I
> can be sure that the problem is actually fixed.  It's aggravating...
>
> It doesn't seem to be the final destination carrier that's screwing up the
> call routing after having received the call: I can call the same number
> over and over again through a "reputable" carrier, or via my personal cell
> (but I repeat myself), and get connected to the right destination every
> time.  Based on my experiences, I highly doubt the misdirected calls are
> even getting as far as the CO's switch for that exchange.
>
> So I have to hypothesize that some sketch carrier getting is picked from
> an LCR table, one who just doesn't like sending the call to a rural carrier
> who either charges that much, or that they suspect is engaging in fraud.
> But...WHY *misroute* it?  I'd rather you just reject the call if you don't
> want to carry it.
>
> The misrouted calls in this latest case more often than not seemed to be
> hitting a foreign voicemail system that sounded an awful lot like AT&T
> Mobility's default voicemail greeting.  But we have definitely had calls
> just end up ringing the absolute wrong phone...in one case a few months
> back, I tried ringing the public library branch in this one rural town, and
> ended up getting the answering machine for some random business (...and
> also the call quality was *abysmal* on top of that).  (Never did manage to
> figure out where that business whose answering machine I got was actually
> located.  It was a generic-enough name for a business in their industry,
> but what I can tell you is that there was no business by that name in the
> rate centers covered by that rural carrier.  And also that my CDRs back up
> the fact that I did *not* mis-dial that call.)
>
> About the only theory I can come up with that makes a lick of sense is
> that these cut-rate carriers in these LCRs decide to throw to a rando
> number if they get asked to term to a high-cost exchange, so that they can
> record a call completion and charge the caller for it anyway.  Which would
> be a form of fraud itself, if that's actually happening.
>
> I suppose there could be a leg of the call that is being signalled
> non-digitally (so, not SS7, not SIP, ...), and something is getting either
> mis-transmitted or mis-interpreted.  But if they were doing something like
> (e.g.) in-band DTMF over a crap connection to an old switch somewhere, I
> would expect dropped digits, and thus not enough to construct a viable &
> valid destination number out of.
>
> -- Nathan
>
> ___
> VoiceOps mailing list
> VoiceOps@voiceops.org
> https://puck.nether.net/mailman/listinfo/voiceops
>
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